4TH YEAR OF ENGINEERING STUDENT CONFERENCE · 2018-05-01 · 2018 U Q | E N G I N E E R I N G S T U...

34TH YEAR OF ENGINEERING STUDENT CONFERENCE

Thursday, 3 May 2018

2 0 1 8 U Q | E N G I N E E R I N G S T U D E N T C O N F E R E N C E

WELCOME

I warmly welcome you to our Engineering Student Conference in the School of Mechanical and Mining Engineering. We are looking forward to a range of presentations from all students in the School this year. The Engineering Student Conference provides our undergraduate honours and coursework master’s thesis cohort the opportunity to present their research to an audience of academics, their peers and engineering professionals. This is a great experience for presenters and offers the opportunity to learn more about the extensive research undertaken across the School. This network is the next generation of engineers and so I encourage you to strengthen your links with your peers now, as they could be your future colleagues, collaborators or leaders. This conference forms an important part of the training experience in the School, providing an opportunity for our students to supplement their technical and scientific training with essential transferable skills in communicating the impact of their studies and conversing with others. Our research community actively pursues excellence in research, promotes collaboration, fosters integrity, and encourages creativity and innovation and this is demonstrated today by all of our students who showcase the high quality and broad range of expertise across our School. I am confident you will find this an engaging and beneficial experience.

Professor Andrej Atrens Theses Course Coordinator School of Mechanical and Mining Engineering

The University of Queensland


CONTENTS

WELCOME ....................................................................................................... 1

MESSAGE FROM THE CONFERENCE COORDINATOR .............................. 2

VENUE MAP ..................................................................................................... 3

SUMMARY OF CONFERENCE DUTIES ......................................................... 4

ORDER OF PROCEEDINGS ............................................................................ 5

SESSION TIMES .............................................................................................. 6


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MESSAGE FROM THE CONFERENCE COORDINATOR

On 3 May 2018, you will communicate your ideas formally to a group of your colleagues and

you will receive useful feedback related to your thesis project. The programme follows the

form of a professional symposium, and you should dress and behave appropriately. There will

be many times throughout your career when you will be called upon to give presentations of

technical material. Make the most of this opportunity to develop your presentation skills and

help your colleagues to develop their skills by being constructively critical during the

discussion periods.

Each presentation will be formally assessed by everyone who attends. Please read the

synopses before the talks as assessment includes these.

Attendance at all sessions is compulsory. Make sure you complete your electronic

assessment via Survey Monkey here: https://www.surveymonkey.com/r/SoMME2018. This survey will work on any tablet or mobile device. This will be proof of attendance.

You need to check the schedule to see if you have special duties. A summary of the

Chairperson and Duty Officer roles is provided on page 4. An order of proceedings for each

session is also provided on page 5 to guide you through the session.

PRIZES A small prize will be offered for the best presentation in Mechanical Engineering on the day. These will be selected by a small panel of the academic staff, which will consider the quality of the synopsis and the recommendation of the staff critic. This will be announced and presented at the closing session.

YOUR ACTIVITES DURING THE CONFERENCE

1. A 15-minute presentation: 12 minutes presentation time and 3 minutes question time.

2. Attend all sessions during the day and evaluate the performance of the presenters using

the electronic assessment via Survey Monkey. You do not have to submit an

assessment if you are one of the presenters in the session.

CONFERENCE VENUES St Leo’s College

Bldg 36F

College Road

Professor Andrej Atrens

Theses Course Coordinator Engineering Student Conference, 2018

https://www.surveymonkey.com/r/SoMME2018


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SUMMARY OF CONFERENCE DUTIES

CHAIRPERSON

The timing for all sessions is critical, to permit the audience to move between parallel sessions as they wish. Most sessions are made up of presentations that have related subject matter and a common theme. The Chairperson is responsible for:

The timing of presentations within their sessions, and must use the following timetable:

2 min - General session introduction by Chairperson

12 min - Speaker’s Presentation

3 min - Questions from the Audience

5 min - Staff Critic’s closing remarks

Please see the next page for a full summary of Chairperson duties.

DUTY OFFICER

The role of the Duty Officer is to ensure that everything runs smoothly for the presenters.

The Duty Officer is responsible to:

1. Ensure that the room is prepared and that the scheduled staff critic is present, and

2. For each speaker - a. Assist the speaker to locate their presentation

on the computer. b. During each presentation, help the presenter

or the Chairperson when needed. c. Make sure the room is comfortable for the

occupants (lighting, noise, etc.) and try to solve any problems associated with the venue; and

d. Report to the conference coordinator if a problem is too difficult to resolve.

If you are Duty Officer for the last session of the day in your room, please pack up the presentation equipment (computer/laser pointer etc). Take to the Conference Foyer for collection by School staff.


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ORDER OF PROCEEDINGS

BEFORE THE START OF THE SESSION

Presenters report to the session Chairperson. The Duty Officer ensures that the room is prepared (presentation files are ready) and that the scheduled staff critic is present.

DURING THE SESSION

Chairperson’s introduction (2 minutes)

Announces the start of the session

Self-introduction

Introduces the Duty Officer

Introduces scheduled speakers and their topics

Introduces the staff critic

Advises time limits of each presentations (12 minutes + 3 minutes)

Reminds students of the electronic assessment via Survey Monkey

Welcome the first presenter

Presenter One (12 minutes presentation + 3 minutes questions)

At 11 minutes the Chairperson provides a 1 minute warning

At 12 minutes the Chairperson asks the speaker to stop and calls for applause

The Chairperson asks for questions from the audience. The Chairperson identifies who has a question and handles the discussion. The Chairperson asks the first question if none are forthcoming from the audience.

At 15 minutes the Chairperson closes the discussion and calls the next presenter.

Students complete the electronic assessment via Survey Monkey

Presenter Two onwards

Repeat steps above

Last Presenter (12 minutes presentation + 3 minutes questions)

Repeat steps above

Staff critic’s comments (5 minutes)

Chairperson thanks everyone and concludes the session.

NOTES: Let us work together to make the conference a successful event. Chairpersons are requested to spend a little time before the conference to practice. They should speak loudly and effectively control the session (introduce speakers, invite questions, control time etc.).


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SESSION TIMES – ST LEO’S COLLEGE

Venue A

Leonian

Venue B

BoardroomVenue C

LibraryVenue D

McKenna

Venue E

Tute Room 2

8:30-8:35 Welcome by Professor Andrej Atrens, Boardroom

8:37-10:29 A1

Materials

B1

Materials 4

C1

Batteries 1

D1

Mechanical 1

E1

Mining

10:30-10:45 Morning Tea

10:47-12:39 A2

Materials 2

B2

Materials 5

C2

Batteries 2

D2

Mechanical 2

E2

Biomaterials

12:40-13:20 Lunch

13:22-14:59 A3

Materials 3

B3

Aerospace

C3

Civil

D3

Mechanical 3

E3

Mechanical 4

15:30-15:40 Closing Presentation by Professor Andrej Atrens, Boardroom


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CONFERENCE PROGRAMME Venue A1:Materials 1

Leonian Venue B1: Materials 4

Boardroom

Chair Joshua Mones

Staff Critic Kazuhiro Nogita

Duty Officer Valentine Bouet

Chair Jiakun Zhang

Staff Critic Andrej Atrens

Duty Officer Blake Phillips

Time Title Presenter Title Presenter

8:37 Chair’s Introduction Chair’s Introduction

8:39 Modification and Characterisation of Cast Mg-Al-RE Eutectic Alloys

P.A.D Asanthi Dinithik Appuhamy

Pre-Pregnation of Polymer to Ceramic Resins Taylor Pratt

8:54 Performance Benchmarking for Ni-Hard Ore Chute Liner Alloy - BMECT

Mohamed Hanif Mohd Hamzah

Aerospace Framework for Rapid Prototyping of UAV’s Rodolfo Rodriguez

9:09 Developing an Ideal Boron-Based Grain Refiner for Titanium 64

Zac Connor A Comparison Between Pure Titanium and Biomedical Titanium Alloy

Wilson Vo

9:24 Characterisation of the Fluidity of Zn-Al Alloys Daniel Costello Evaluate a Novel Top Surface Analysis Method to Determine the Mode I Fracture Toughness of Materials and Interfaces

Shalini Priyaa Siddharthan

9:39 A Comparison Between Pure Titanium and Biomedical Titanium Alloy

Rylan Dawson Understanding the Nexus between Abrasion Resistance and Fracture Toughness in Ceramics — Ball Mill Abrasion Test and Ball Mill Edge Chipping Test

Rugeshrajah Selvarajah

9:54 Grain Refinement on Magnesium Alloy Muhammad Ikhwan Deni

(G66) Understanding the Nexus Between Abrasion Resistance and Fracture Toughness in Ceramics – IC-SBAT and IC-CPAT

Sam Wilson

10:09 Investigation into the Biocompatibility of Porous Ti35Zr28Nb and Grade 2 CP Titanium under Artificially Simulated Conditions

Matthew Heywood The Influence of Process Parameters on Surface Roughness, Micro-Structure and Mechanical Properties of Thinned-Walled Alumina Using Laser Engineered Net Shaping (LENS)

Wei Feng Tye

10:24 Staff Critic Comments Staff Critic Comments

Morning Tea


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CONFERENCE PROGRAMME Venue A2: Materials 2

Leonian Venue B2: Materials 5

Boardroom

Chair Zac Connor

Staff Critic Jeff Gates

Duty Officer Matthew Heywood

Chair Maxwell Buckley

Staff Critic Mingzing Zhang

Duty Officer Alex Grunke


10:47 Chair’s Introduction

Chair’s Introduction

10:49 Aluminium Plastic Deformation Limits for Incremental Sheet Forming

Jordan Hodges Model Based Predicative Control of a Solar Thermal-Diesel Hybrid System

Nisala Herath

11:04 A Comparison Between the Microstructure and the Mechanical Properties of Pure Titanium and Biomedical Titanium Alloy

Amir Arsyad Khairuddin

Cd-Doped Tin Selenide Thermoelectric Materials Angyin Wu

11:19 Controlling the Microstructure of Titanium Alloys Through Solidification Processing

Jack Krynen Stress Corrosion Cracking of Pure Mg and Mg Alloys WE43 and EV31 in 0.1mol/kg 𝑵𝒂𝟐𝑺𝑶𝟒 Saturated with 𝑴𝒈(𝑶𝑯)𝟐

Yifeng Li

11:34 Development of Test Methodology to Assess the High Temperature Corrosion of Pre-Stressed Samples

Xe Jian Lee High Temperature Polymer Matrix Materials for Next Generation Fibre Reinforced Plastics

Antoine Pouliquen

11:59 Understanding the Influence of Paint Baking on the HE Susceptibility of some MS-AHSS

Fang Yan Lim Exhaust Gas Heat Recovery in Diesel Engine Using Organic Rankine Cycle

Tushar Karad

12:04 (G65) Performance Benchmarking for NiHard Ore Chute Liner Alloys

Tim Chen Affordable Tooling/Manufacturing for Small Scale Production Marlunn Eric Oducayen

12:19 (G65) Performance Benchmarking for NiHard Ore Chute Liner Alloys — IC-SBAT and RWAT

Will Marnane Characterisation of Surface Tension of Zn-Al based Alloys Day Weng Tan


Lunch


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CONFERENCE PROGRAMME Venue A3: Materials 3

Leonian Venue B3: Aerospace

Boardroom

Chair Jordan Hodges

Staff Critic Michael Bermingham

Duty Officer Fang Yan Lim

Chair Marlunn Eric Oducayen

Staff Critic Rowan Gollan

Duty Officer Tushar Karad



13:24 An Investigation of the École Centrale Paris (ECP) Plasma Torch

Jack O'Brien Investigation of the X2 Expansion Tube’s Primary Diaphragm Rupture Process using Light 316 Stainless Steel Foil

Paulo Alvear Fujii

13:39 Developing a High Strength Titanium Alloy Xiao Ma CFD Design of Square-Cross-Section Nozzles for the Expansion Tunnels

Adeline Mary Augustine

13:54 Understanding the Influence of Paint Baking on the HE Susceptibility of some AHSS

Suyu Zou 2D Model of Slow Flying Paper Planes Nathan Lu

14:09 Effect of Solute Additions on the Microstructure and Mechanical Properties of High-Entropy Cast Mg-Al Based Alloys

Jingwei Hu Validation of Wall Function for Reducing Computational Cost of Wall-Bounded Turbulent Simulations in Eilmer4

Ying Xiang Dimir Pot

14:24 Research on Effect of Multi-Additions on Hardness and Micro-Structure of High Entropy Mg Alloy Based on Mg-3Al

Shaowen Bai Design of Large Non Reflected Shock Tube for Radiation Studies Yen Cherk Teoh

14:39 Investigation on Effect of Multiple Elements Addition on the Properties and Microstructure of Cast Magnesium Alloys

Peilin Li Modelling the Entry of a Scramjet Based Vehicle to Space Eduardo Andres Urresta Alban

14:54 Influence of Pre-Treatment on Hydrogen Permeability in Martensitic Advanced High Strength Steels

Yifan Wang An Equilibrium Chemistry Module for the Eilmer4 Flow Simulation Code

Hugh McDougall

15:09 Staff Critic Staff Critic

Closing Presentation


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CONFERENCE PROGRAMME Venue C1: Batteries 1

Library Venue D1: Mechanical 1

McKenna

Chair Hugh McDougall

Staff Critic Ruth Knibbe

Duty Officer Xiao Ma

Chair Adeline Mary Augustine

Staff Critic Peter Jacobs

Duty Officer Jack O'Brien



8:39 Increasing the Sulfur Loading in a Lithium-Sulfur Battery

Ashley Abinash Anthony

CFD Validation of Centrifugal Compressor Performance Wei Chuang

8:54 Commercial Scale Recycling of Lithium Ion Batteries in Australia

Maxwell Buckley A New Perspective of Lithic Reduction in Archaeology: Numerically Simulating Flintknapping with Peridynamics

Matthew Day

9:09 Li-Ion Battery Recycling Blake Dykes Top Surface Analysis Measurement Techniques for Mixed Mode and Mode II Fracture Toughness Values of Materials and Interfaces

Shane Evans

9:24 Degradation Mechanisms of Lithium Ion Battery Ahadhim Dary Ismaya Flexural Fatigue Properties of a 3D Printed Polymer for use in Orthotic Insoles

Mark Fitzpatrick

9:39 Lithium Ion Battery Recycling Mario Alejandrio Torres Cedeno

Development of High Performance Cycling Shoes Using Advanced Composite Materials

Alex Grunke

9:54 The Degradation of Lithium-Sulfur Battery Lianbang Kou Fire Whirls: Generation Mechanisms Andre Sebastian Jaramillo Paredes

10:09 The Grain Size of Sulfur in Cathode of Lithium-Sulfur Battery Influence the Battery’s Performance

Jiechen Gan Staff Critics Comments

10:24 Staff Critics Comment

Morning Tea


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CONFERENCE PROGRAMME Venue C2: Batteries 2


McKenna

Chair Mark Fitzpatrick

Staff Critic Paul Meehan

Duty Officer Wei Chuang

Chair Shane Evans

Staff Critic Hal Gurgenci

Duty Officer Matthew Day



10:49 Mapping Battery Systems around the World Pengfei Liu Finite Element Analysis of Imperfect Structural Sections Under Compression

Andrew Tang

11:04 Application Of Solar Power On Air Conditioning In Closed Greenhouse

Huang Hui Numerical Study of Aerodynamic Analysis of Typical Blades on Darrieus Type VAWTs

Yueyang Jiang

11:19 Oxidation Stimulation Technique to Enhance Coal Permeability: Mechanism of NaClO Reaction with Different Coal Macerals Composition

Ziqiang Liu Piston Braking System for X3R Kunfeng Gao

11:34 Electrolyte for Lithium-Sulfur Battery YiShu Chang Biomedical Meets Robotics: Deep Brain Stimulation Soraya Brosset

11:59 Understanding the Impact of Connected Environment on Human Factors Using Car-Following Model

Rajath Krishnamurthy Sweet Arm Robot Sebastien Sutter


Lunch


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CONFERENCE PROGRAMME Venue C3: Civil


McKenna

Chair Pengfei Liu

Staff Critic Dilum Fernando

Duty Officer Rajath Krishnamurthy

Chair Andrew Tang

Staff Critic Michael Heitzmann

Duty Officer Sebastien Sutter



13:24 Beach Erosion at Amity Point Clara Taverne Investigations into the Aromatic Ketene-Claisen Reaction Jiakun Zhang

13:39 Tensile Strength Perpendicular to Grain of Timber Wentao Lyu Pre-Fabricated Folded Structures Shashank Bhandary

13:54 Application of Limestone and Glass Dust in Concrete Pavement

Enbo Kang Entering the Knowledge Society - A Challenge for Engineering Education Across the Globe

Lu Wang

14:09 Leveraging Additional Capacity out of Telstra Mobile Structures

Philip Dieters Machine Learning for High Temperature Solid Oxide Fuel Cell Cathode Development

Zhiyue Wang

14:24 Shade Cloth Rollover Project Graham Anderson Design Review of Temperature & Pressure Relief Valve Blake Phillips

14:39 BIM-Based Application Framework for Construction Lifecycle Management

Zhongying Du Refinement of Occupational Health and Safety Systems in Gelatine Manufacture

Brendan Jenkyn

14:54 Determination of the Burning Behaviour of a Timber at a Bench-Scaled31

Qin Cai Staff Critic Comments

15:09 Staff Critic Comments



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CONFERENCE PROGRAMME Venue E1: Mining

Tute Room 2

Marker Christopher Leonardi

Time Title Presenter

8:37 Implications of Dump Truck Loading on Tip Head Stability

Boitumelo Gabofele

8:52 Blasting Near Sensitive Structures at the Mangoola Open Cut Mine

John Beaton

9:07 A Comparison of Visual Methods for Generating Digital Point Clouds

Russell Webster

9:22 University Of Queensland Experimental Mine Minewater Assessment

Cameron Stubbins

Morning Tea


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CONFERENCE PROGRAMME Venue E2: Biomaterials

Tute Room 2

Chair

Muhammad Ikhwan Deni

Staff Critic Alex Klimenko

Duty Officer Daniel Costello



10:49 Modelling the Deformation Behaviour of Porous PHBV Bone Scaffold Implants Under Compressive Stress

Rushabh Patel

11:04 Innovative Wound Closure Devices John Yap

11:19 Improving the Corrosion Resistance of Bio-Compatible Mg Alloy with HA Coating

Yueyao Xiao

11:34 Comparison of Corrosion of Magnesium, Iron and Zinc in Air and Simulated Human Condition

Yaxin Zheng

11:59 Polymer Coating on Biodegradable Magnesium Alloy

Yuan Xie

12:04 Electroplating Zinc on Magnesium as a Biodegradable Material

Zihao Fu

12:19 Staff Critic Comments

Lunch


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CONFERENCE PROGRAMME Venue E3: Mechanical 4

Tute Room 2

Chair

Soraya Brosset Staff Critic Bill Daniel

Duty Officer John Yap



13:24 Estimation of Intermediate Shapes for Incremental Forming

Joshua Mones

13:39 Whole of Life Costing Review for Major Mobile Equipment 2018

Timothy Ross

13:54 Sub-Cooled Solar Thermal Plant Modelling Keyuan Zeng

14:09 Design of Hydraulic Bottom-Out Control for Mountain Bike Suspension

Ben Brunckhorst

14:24 Foot Arch Exoskeleton Design Marcus Daldy

14:39 Modelling of Complex Competitive Systems Applied to the Study of Technical Revolutions

Valentine Bouet

14:54 Staff Critics Comments


Back to Conference Programme

SYNOPSES A1: Materials 1

Modification and Characterization of Cast Mg-Al-RE Eutectic Alloys

P. A. D Asanthi Dinithika APPUHAMY 43355435

Supervisor: Prof Kazuhiro Nogita and Dr Stuart McDonald

Due to increased interest in reducing fuel consumption in the automotive industry, lightweight Mg-

Al alloys are becoming more desirable for use. The most commonly used alloys have poor creep

performance when the temperature surpasses 120 C. This is due to the precipitation of the β-

Mg17Al12 phase which is unstable beyond 120 C (Rzychon, 2006). However, Zhu et al has shown

that creep performance could be improved by adding rare earth metals due to the preferential

formation of the Al11RE3 and Al2RE intermetallic phases (Zhu, Nie, Gibson, Easton, & Bakke,

2012). Zhang et al has found that the Al11La3 and Al11Ce3 phases are the most stable eutectic phases

formed. (Zhang et al., 2009). This thesis involves the refinement of the Mg-Al-Ce phase diagram by

analysing the eutectic phases in the microstructure and finding their eutectic points through thermal

analysis.

Eight castings were prepared with varying compositions of Al ranging from 2%-0% and Ce ranging

from 18%-10%. For the high Ce and Al content samples, the microstructural analysis showed three

phases apart from the -Mg which appeared in a dendritic form. The three phases were identified to

be Mg12Ce which appeared light grey and occupied most of the volume of the sample; Al11Ce3 which

appeared as plate like bright particles and a small quantity of intermetallic particles of AlCe/Al2Ce.

In order to identify the exact point where the eutectic reaction takes place, the next batch of samples

were cast with low Al and Ce content to reduce the formation of the intermetallic particles. The

microstructural analysis of these samples revealed a major reduction of the said intermetallic

particles, but the Mg12Ce and Al11Ce3 eutectics had also reduced. However, an increase of Al from

0.5% to 1.5% showed a significant increase in the Al11Ce3 eutectic. The thermal analysis allowed to

identify the temperatures at which the above-mentioned phase reactions occurred.

In conclusion we have been able to further develop an understanding as to where the eutectic point of

the Mg-Al-Ce phase diagram at the Mg rich corner lies. The full thermal analysis is yet to be

conducted along with the microstructural analysis of the last two cast samples, but upon their

completion at the end of the semester a further refined phase diagram for the above system could be

achieved.

REFERENCES

Rzychon, T. K., A. (2006). Effect of rare earth elements on the microstructure of Mg-Al alloys.

Journal of Achievments in Materials and Manufacturing Engineering, 17(1-2).

Zhang, J., Liu, K., Fang, D., Qiu, X., Tang, D., & Meng, J. (2009). Microstructure, tensile properties,

and creep behavior of high-pressure die-cast Mg–4Al–4RE–0.4Mn (RE = La, Ce) alloys. Journal of

Materials Science, 44(8), 2046-2054.

Zhu, S. M., Nie, J. F., Gibson, M. A., Easton, M. A., & Bakke, P. (2012). Microstructure and Creep

Behavior of High-Pressure Die-Cast Magnesium Alloy AE44. Metallurgical and Materials

Transactions A, 43(11), 4137-4144. doi:10.1007/s11661-012-1247-9



Performance Benchmarking for Ni-Hard Ore Chute Liner Alloy - BMECT

Mohamed Hanif MOHD HAMZAH

Supervisor: Dr Jeff Gates

Ni-Hard are a class of high wear resistant white cast irons that are alloyed with nickel and chromium.

This characteristic, especially resistance to abrasion, has made Ni-Hard a popular choice for

industrial processes (Nickel Institute, n.d.).

Apart from abrasion resistance, this research also looks at the material’s toughness by measure of its

edge chipping. Thus, two methods of experiments were performed for the research. Namely they are

the Ball Mill Abrasion Test (BMAT) and the Ball Mill Edge Chipping Test (BMECT). For the

seminar, I will present mostly on the BMECT part.

The BMECT experiment aims to look at the edge toughness performance of Ni-Hard compared

against other white cast irons with higher amounts of chromium. The experiment utilizes UQ

Materials Performance’s laboratory ball mill, a smaller version of an industrial ball mill.

As much as the experiment is about testing material performance, it is also to continuously improve

on the experiment methods. The BMECT is a relatively new method of testing edge toughness or

edge chipping. A few researches in the past have performed the BMECT on a few different

materials, mainly steel and white cast irons. This experiment now looks particularly at a specific

class of white cast irons (Ni-Hard 4) and high-chromium white cast irons. There are colleagues who

will be performing the experiment using ceramics but that is out of the scope of this presentation.

The BMECT involves the specimens being exposed to grinding balls mixed with a cushioning

material, talc in this case, and water. The experiment was run at set intervals. The mass of each

specimen was recorded before the experiment and after each subsequent test intervals. The mass

losses of the specimens were then recorded and compared against a few variables.

The mass losses of the specimens were compared against time and the materials’ bulk hardness. The

other variables to measure against are the chromium to carbon ratio (Cr/C) and the carbide-volume

fraction present in the microstructure (CVF). At this point, information on these two variables is in

the process of being acquired.

When compared against time, there is quite a scatter of results. This likely meant the conditions of

the experiment may still not be just right. It is highly desirable to achieve that as the ball mill

apparatus allows for many specimens to be tested simultaneously, increasing the efficiency of

experiments.

Comparison of mass loss against specimen bulk hardness show no obvious correlation with each

other. It has been noted by the Nickel Institute (n.d.) that hardness is an approximate indicator of

material tougheness. However, also note that the materials tested were similar in properties and the

range of their hardness is very narrow – between 720 to 890. Further comparisons against Cr/C and

CVF will be made to uncover more of the materials’ performance.

REFERENCES

Nickel Institute, n.d. Ni-Hard Material Data and Applications, s.l.: s.n.



Developing an Ideal Boron-Based Grain Refiner for Titanium 64

Zac A. CONNOR

Supervisor: Dr M. Bermingham

Ti-6Al-4V, commonly known as Ti-64, is the most commonly used alloy, frequently for aerospace

applications for its high strength combined with its comparatively low weight (U.S Titanium

Industry Inc. 2002) Like other metals, grain refinement can be used to enhance its properties, making

the alloy even stronger by decreasing the grain size as described by the Hall-Petch equation. Previous

studies have shown that 0.1% wt B in the alloy from grain refinement efficiently reduces the size

(Tamirisakandala 2005), but it has yet to be determined which Boron-based grain refiner has the best

effect on the alloy. 7 different aluminium-boron alloys were provided by KBM Master Alloys in

order to be used as grain refiners for Ti-64, in order to determine if one of the alloys provides greater

properties than the others when used as a grain refiner.

The components of each grain refiner were charted, and an equation was developed to determine

how much grain refiner, aluminium, titanium, and a Vanadium-Aluminium alloy to add together to

complete a Ti-64 alloy with 0.1% boron. These amounts were subsequently measured, cut, ground

and set aside before casting the alloys. The cast samples were then cut in half to expose the internal

microstructure, before the surfaces were ground and polished using hydrofluoric acid to fully reveal

the microstructure. The samples were then put under an electron microscope, where the

microstructures of the samples were captured at various magnifications along with scans of the

components of the alloys. Once the microscopies were captured, the alloys were then tested for

Vickers hardness using a 2 kg load for 12 seconds. 10 hardness values were obtained for each sample

and were used to find an average hardness for each sample. The microstructures of each sample are

incredibly similar, with white needle-like Ti-64 grains with veins of black Ti-B dendrites between

the grains. The compositions of the samples reveal that the Ti-64 successfully formed through most

of the samples, with some variance. While the hardness values vary slightly, they don’t reveal any

significant difference, as most of the variance is more likely caused by the variance in the

components of the alloy and errors in the creation of the alloy.

Based on the similar microstructure and hardness values, the samples are shown to not be

significantly different from each other, meaning none of the grain refiners have a particularly

preferable effect on refining Ti-64. This means that any boron-based grain refiner can be used, as

long as the caster correctly creates the 6% Aluminium, 4% Vanadium, and 0.1% Boron ratio in the

alloy using the grain refiner.

REFERENCES

U.S. Titanium Industry Inc. 2002, Titanium Alloys – Ti6Al4V Grade 5. AZO Materials.

S. Tamirisakandala, R.B. Bhat, J.S. Tiley & D.B. Miracle 2005, Grain refinement of cast titanium

alloys via trace boron addition. Scripta Materialia, Volume 53, Issue 12.



Characterisation of the Fluidity of Zn-Al Alloys

Daniel D. COSTELLO

Supervisor: Prof K. Nogita

Requested by an industry leading steel manufacturer, this project investigates the fluidity

characteristics of three different Zn-Al coating alloys after a surface defect began appearing on their

product. The defect developed after changing from a Zn-Al coating to one containing Zn-Al-Mg. The

addition of magnesium results in a significant increase in corrosion resistance (Marder, 2000) so the

manufacturer is interested to know what material properties have been altered that lead to the defect

when inserted into their production line. The project aims to characterise each of the coating alloy’s

fluidity properties by investigating what effect the inclusion of magnesium has in order to further

understanding of why the defect is forming and then make recommendations for how it could be

eliminated if fluidity is a major contributing factor.

Castability testing has long been used as a method of quantifying fluidity properties (Campbell,

2015). Thermal analysis was performed first. Measurements for flow distance were then taken from

the Ragone vacuum fluidity test and sand mould casting tests. Optical and scanning electron

microscopy was used on samples from each test. Experiments were performed using the same

furnace temperature as the manufacturer, and then re-performed at the same superheat after initial

experiments were completed.

Fluidity testing indicated that the Zn-Al-Mg alloy had a higher fluidity than the Zn-Al alloy with a

longer average flow length in the vacuum testing. The casting tests were inconclusive. Repeating the

vacuum fluidity tests with same superheat for each coating alloy gave near identical fluidity results

for both the Zn-Al and Zn-Al-Mg. Thermal analysis showed that the alloys containing magnesium

had a lower liquidus temperature. The excess superheat during production and resulting higher

fluidity of the Zn-Al-Mg alloy is now theorised to be contributing to the formation of the surface

defect. Further study into this phenomenon is then recommended.

REFERENCES

Campbell, J., 2015. Complete casting handbook : metal casting processes, metallurgy, techniques

and design 2nd ed., Amsterdam, Netherlands: Butterworth-Heinemann.

Marder, A.R., 2000. The metallurgy of zinc-coated steel. Progress in Materials Science, 45(3),

pp.191–271.



A Comparison Between Pure Titanium and Biomedical Titanium Alloy

Rylan Hugh DAWSON

Supervisor: Dr Hooyar Attar

Titanium is widely known as a highly strong metal with a lower density compared to that other

metals. Mostly due to this characteristic, titanium is widely used in many applications throughout

various industries including automotive, aerospace and even construction industries. However, due to

certain exceptional bio-functionalities, titanium is increasingly being used for biomedical

applications.

This investigation looks at the comparison of pure titanium and titanium alloys in an attempt to

develop an alloy more suitable replacement for biomedical applications. The overall goal of this

investigation is to “find a titanium alloy with properties similar to that of human bone, where upon

pure titanium will be used as a reference point”. The mechanical properties of Titanium indicate that

the Young’s Modulus of pure Titanium is approximately 120GPa, which comparatively to that of a

human bone (3 – 40GPa) is significantly higher (Kuroda, 2016). Thus this investigation aimed to

lower the Young’s modulus of Titanium through alloying elements whilst maintaining a sound

microstructure. Since some alloying elements have been known to cause allergic reactions or

neurological disorders, it was vital to select appropriate elements that are biocompatible. Thus the

use of “β-stabilizers, which change its microstructure and mechanical properties, will make these

materials more promising for biomedical use” (Kuroda, 2016). The most suitable elements to achieve

this include Niobium and Molybdenum.

The use of Niobium and Molybdenum as alloying elements both has a positive effect on decreasing

the Young’s modulus of Titanium. Both Niobium and Molybdenum “are known as the most effective

β-stabilizers in titanium” (Hilditch, 2015). Due to this, what was originally α-phase-dominated

structure is transformed into a β-phase due to the intensity of the alloying elements. The composition

of the Titanium alloys that were investigated include:

Ti – 10Nb

Ti – 10Nb – 5Mo

Ti – 10Nb – 10Mo

In terms of mechanical properties, the Young’s Modulus was recorded to decrease with the addition

of Niobium but more so with increasing Molybdenum content. This is due to the fact that

Molybdenum compared to Niobium, is a significantly stronger β-stabilizing element. This was

confirmed through the microstructural analysis of the alloys investigated. As the level of

Molybdenum content increased, white contrasting areas of β-phase increased with small varying

areas of grey contrast of α + β phase still present. In addition to the microstructural analysis of the

different alloys, it was evident that grain size grew smaller, finer and more “needle like” with the

addition of Niobium compared to the original pure Titanium. And even more so as the level or

Molybdenum content increased.

REFERENCES

Hilditch, Nazari & Nouri 2015. Mechanical properties and microstructure of powder metallurgy Ti–

xNb–yMo alloys for implant materials. Materials and Design. Materials & Design, vol 88, pg1164-

1174. School of Engineering, Deakin University, Geelong, VIC 3220, Australia

Kuroda PAB, B. M. 2016. Effect of molybdenum on structure, microstructure and mechanical

properties of biomedical Ti-20Zr-Mo alloys. Univ Estadual Paulista, Laboratório de Anelasticidade e

Biomateriais, Institute of Biomaterials, Tribocorrosion and Nanomedicine, Brazilian Branch.



Grain Refinement on Magnesium Alloy

Muhammad Ikhwan DENI

Supervisor: Prof Mingxing Zhang

Magnesium is well-known as the lightest metal elements among all. However, magnesium is rarely

used without alloying with other metals. Magnesium’s light weight attribute as well as its good

strength and ability to resist corrosion makes it very popular in the alloy industry and commonly

used in structural alloys (Polmear, et al., 2017). Common application of magnesium is used in

automobile parts where magnesium often used with its sister metal, aluminium to produce steering

wheels, support brackets, instrument panels, etc. Over the years, research on methods to improves

magnesium alloys have been studied and grain refinement method, which can improve the strength

of the metals without scarifying the ductility is one of them.

The focus of the project is to study the effect of grain refinement on cast magnesium alloys using

zinc oxide coated with silica film. By studying the grain refinement effect, it will give an insight to

consider coated zinc oxide as an alternatives additive substance for the purpose of inoculation. In

coherence with the main objective, several minor objectives but necessary are identified to justify the

use of coated zinc oxide as the refiner for cast magnesium alloys.

1.To study the available theories of grain refinement on cast magnesium and magnesium alloy. The

history and factors affecting grain refinement on magnesium and magnesium alloys can be

considered to give better understanding of features that promotes grain refinement.

2.To study the existing problems using typical grain refiners on cast magnesium and magnesium

alloy including zinc oxide and other available refiners. The current faced problems in the commonly

used grain refiners can be discussed to understand the difficulties and limitations faced by the

industries.

The effect of the grain refinement will be conducted by permanent mould casting method where the

refiners will be added in the melt of magnesium and magnesium alloy. The addition amount will then

be increased to observe the refinement variation and to obtain scientific curve. The cast magnesium

will then be prepared, and the microstructure of all magnesium samples will be analysed.

The expected outcome from this project is to compare the effect of addition of coated zinc oxide and

normal zinc oxide on magnesium. Also, comparison of the effect of addition of coated zinc oxide to

magnesium and magnesium alloy. The outcomes for this project can be used to compare with further

studies to find better refiners that suitable in term of cost, efficiency, and convenience.

Optimistically, using coated zinc oxide is an alternative that will give better refinement effect on

magnesium and magnesium alloy.

REFERENCES

Polmear, I., St John, D., Nie, J.-F. & Qian, M., 2017. Magnesium Alloys. In: Light Alloys Metallurgy of the

Light Metals. s.l.:Matthew Deans.



Investigation into the Biocompatibility of Porous Ti35Zr28Nb and Grade 2 CP

Titanium under Artificially Simulated Conditions

Matthew J. HEYWOOD

Supervisor: Prof Andrej. Atrens

Titanium alloys have a wide variety of biomedical applications and are currently the world’s most

widely used biomedical alloy. These alloys must exhibit specific material properties for each

application to ensure a successful treatment. The alloys must show biocompatible properties when

used for implants, specifically a resistance to corrosion induced through chemical imbalance (H.

Rack).

The project aims to assess the corrosion behaviour of porous Ti35Zr28Nb compared to

commercialpurity CP Ti Grade 2 under crevice corrosion testing conditions, Hank’s solution at 37℃

and 3.5 w.t.% NaCl solution at 95℃. This is done through analysis of the samples corrosive

properties using open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and

potentiodynamic polarisation curves. Previous studies completed by (M.P.et. Al) investigated trends

for EIS spectroscopy for Ti-6Al-4V and Ti-6Al-7Nb alloys with incrementally altered surfaces,

which showed comparible bode plot charactertics.

Two sets of porous samples were immersed in Hank’s solution and 3.5 w.t% NaCl for a 28-day

timeframe. Results of the immersion test showed that negligible weight loss had occurred. SEM

analysis of the sample side’s porous structure did not indicate the presence of raised concentrations

of oxygen (O2) ions. The small discrepancies in weight change of the samples were thus attributed to

defects caused by the lateral compression of the samples whilst installed in the assembly platforms.

The NaCl and Hank’s tests indicated that both the Ti35Zr28Nb and grade 2 CP Ti were not

susceptible to crevice corrosion under biological conditions.

The EIS, OCP, and PC electrochemical tests for were completed with the use of a PARStat advanced

potentiostat. Electrochemical testing for EIS, OCP and PC was at first hindered by the thick modular

oxide layer on the sample’s surface. The oxide layer caused a deficient electrical connection between

the alloy, oxide and gave results which were not reproducible. This issue was bypassed by immersing

the samples in 15:1 HF/NO3 acid to remove most of the oxide layer. The set of second tests gave

reproducible results, which were then compared to thermodynamic tables and previously completed

studies. An accurate method for the estimation of the surface area of the porous samples is under

development and may alter the current density on the OCP tests within magnitudes ranging from 1-3.

REFERENCES

H. Rack, "Titanium Alloys for Biomedical Applications," Elsevier, vol. 26, no. 8, pp. 1269-1277,

2006.

M. P. et.Al, "Application of Electrochemical Impedance Spectroscopy for Comparison Analysis of

Surface Modified Ti-6Al-4V ELI and Ti-6Al-7Nb Alloys," Information Technologies in

Biomedicine, vol. 7339, no. 5, pp. 379-388, 2012.


SYNOPSES B1: Materials 4

Pre-Pregnation of Polymer to Ceramic Resins

Taylor PRATT

Supervisor: Dr M. Heitzmann

Ceramic matrix composites also known as CMCs are a group of composite materials consisting of a

ceramic matrix which are reinforced with fibres. The addition of these fibres increases the fracture

toughness of the ceramic matrix which reduces the susceptibility of brittle fracture. The principal

advantages of ceramic matrix composites over other materials is their resilience to oxidation and

deterioration at elevated temperatures, their high melting points, and high compressive strengths

(AZo Materials, 2013).

The current issues facing the advancements of ceramic matrix composites is the fact they are

extremely expensive to manufacture; the manufacturing process is labour intensive and the ceramic

resin matrices are not commonly found.

This thesis investigates the current issues associated with ceramic matrix composites by investigating

the use of pre-pregnation to produce a component with the same ceramic yield as traditional

manufacturing techniques.

Pre-pregnation is a manufacturing technique in which a reinforcing fabric is pre-impregnated with a

resin system. Pre-preg technology is advantageous as it allows for more accurate control of the fibre

volume fraction of the material decreasing the probability of defects and porosity and increasing,

consequently the mechanical properties (Sao, 2005). Pre-pregs also have an advantage over

traditional manufacturing methods as they can be used to form highly complex geometries.

This project investigates the use of two different ceramic forming polymer systems;

SMP-10 a silicon carbide matrix precursor which provides high ceramic yields at low temperatures

between 180-400oC and SPR-688 a Siloxane substitute resin which can be used to form thermosets at

processing temperatures between 180oC and 300oC or ceramics between 850oC and 1,100oC (Starfire

Systems, 2017).

Differential Scanning Calorimetry (DSC) has been performed on the two resin types to help

understand the curing kinetics of the resins. The results from these tests have been used in

connection with a number of tackiness tests to determine a suitable temperature and time scale from

which the pre-preg component should be manufactured.

The next phase of the project is to demonstrate the pre-preg technique is effective by comparing the

ceramic yield of the pre-preg to the ceramic yield obtained via traditional pyrolysis methods. With

the outcome being the production of a complex plate stringer geometry created via the new pre-preg

layup.

REFERENCES

AZo Materials . (2013). Composite Matrix Materials. Retrieved from AZO Materials:

https://www.azom.com/article.aspx?ArticleID=9814

Sao, C. (2005). Characterisation of cure of carbon/epoxy prepreg used in aerospace field. Materials

Research, p141-149.

Starfire Systems. (2017). Ceramic Forming Polymers. Retrieved from Starfire Systems:

http://www.starfiresystems.com/ceramic-forming-polymers.html

https://www.azom.com/article.aspx?ArticleID=9814

http://www.starfiresystems.com/ceramic-forming-polymers.html



Aerospace Framework for Rapid Prototyping of UAV’s

Rodolfo RODRIGUEZ

Supervisor: Dr Ingo JAHN

Unmanned Aerial Vehicles (UAV’s) are becoming more popular by the day. With increasing real-

life applications, the demand for more diverse designs is required. The principal aim of the

framework is to reduce the design time by changing the traditional process, where a prototype had to

be built in for assessment, to an easier approach, where modifications can be implemented in a

software simulation and their effects can be investigated without the need of a physical prototype.

Moreover, the framework should also be able to give information on the limitations of the vehicle to

perform certain manoeuvres or meet goals (time, range... etc.). Ultimately, different designs and

approaches can be simulated to have an idea on the capability of each one of them before the

manufacturing process starts.

The Australian Outback challenge is a competition that tests teams from different parts of Australia

in their ability to create a vehicle that can perform a search and rescue or similar mission types. The

framework specifically addresses vehicles for this competition. It is expected that this framework

will allow to accelerate the design process of the teams. A clear example on the power similar

frameworks is the LaSRS++ by NASA software. This is a software written in C++ which allowed to

complete one of the first Mars Exploration programs in may 2003. Using LaSRS++, NASA took an

original UAV prototype and redesigned it until it demonstrated full capability to perform the

mission. 3 Months of design and virtual testing allowed for this UAV to reach Mars in early stages of

Mars Exploration (Kenney 2003).

An object-oriented approach is to be used for the coding of the framework. This approach allows to

define multiple planes and/or trajectories and build a comparison between them. A plane is defined

by its parameters. The most basic definition must contain at least mass, reference Area, coefficients

of lift and drag. Optional parameters are accepted. The trajectory can be fully or partially defined.

Finally, the framework will also to optimise for a trajectory with proper constraints set for a

particular aircraft. The optimisation will depend on the cost function selected, which can be defined

in terms of time, range, fuel consumption, manoeuvrability or a combination of them. This will allow

to compare each vehicle at its best performance and select the design with the optimum design.

As a validation, the code was tested against a Python built in function called Aero Python. The

results from the Aero Python simulation and the proposed framework show a discrepancy of less

than 1%. Moreover, this will help identify a critical timestep for simulation. This is essential because

the optimization process has a very high computational cost. Reducing the time step can significantly

reduce the computational cost, however, it there must exist a balance between computational cost

and credibility of the results. The optimiser is still in development.

In conclusion, once completed, the framework will allow for faster design of a competitor’s design.

It is important to notice that these frameworks only return data, it is up to the teams to analyse the

data and asses it properly to take decisions on the next steps. However, this approach can save time,

money and other resources.

REFERENCES

Kenney, P. S. 2003, extracted from

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.81.8375&rep=rep1&type=pdf

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.81.8375&rep=rep1&type=pdf



A Comparison Between Pure Titanium and Biomedical Titanium Alloy

Wilson VO


Titanium alloys have seen a large increase in use across biomedical applications in the past century.

These applications include prosthetics, implants, internal fixtures and instrumentation. Its popularity

in the medical field is largely due to titanium’s high strength to density ratio, resistance to corrosion

and its biocompatibility (Rack and Qazi, 2006). Titanium alloys are commonly used over

commercially pure titanium since a range of more desirable mechanical properties can be achieved in

addition to potentially reducing the cost of manufacture (Clayton, 1987). This research looks at iron

as an alloying constituent in order to improve key mechanical properties such as Young’s modulus

and toughness. To see the effects of iron as an alloying material, different weight percentages of iron

will be investigated, namely commercially pure Ti, Ti-3Fe, Ti-6Fe and Ti-9Fe.

The alloys were fabricated using powder metallurgy in which fine powders of both elements were

rigorously mixed and then pressed into shape, where it then undergoes the sintering process. In order

to observe the microstructure of the alloys, the samples were grinded, polished and finally etched in

an acid solution. The micrographs for commercially pure Ti revealed large α-phase (hexagonal close-

packed crystal structure) plates with distinctive grain boundaries. The micrographs for the Ti-Fe

alloys revealed the presence of β-phase (body-centred cubic crystal structure) regions along with

long acicular α in a Widmanstätten or “basket-weave” pattern. The β-phase region grows larger with

higher wt% Fe and the length of α decreases.

A compression test was then performed on the samples to investigate their mechanical properties. It

was found that:

Commercially pure Ti had a Young’s modulus of 67.7 GPa

Ti-3Fe had a Young’s modulus of 72 GPa

Ti-6Fe had a Young’s modulus of 78.2 GPa

Ti-9Fe had a Young’s modulus of 59.2 GPa

It was noted that Ti-3Fe and Ti-6Fe had failed in a brittle fashion as it displayed a characteristic 45

degree angle shear. Pure Ti and Ti-9Fe had failed in a way that was characteristic of a ductile

material.

In conclusion, it was found that increasing Fe content increases the β-phase region of the alloy with α

plates becoming shorter in length size, according to the micrographs. As a result, the Young’s

modulus increased with Fe content with the exception of Ti-9Fe which was observed to be the lowest

at 59.2 GPa. It was also observed that this sample had the highest yield point of all the samples and

showed characteristics of ductile failure. Hence, it can be concluded that iron may be suitable as a β-

stabilising element for biomedical titanium alloys in the right composition.

REFERENCES

Clayton, C.R., 1987. Materials science and engineering: An introduction: by WD Callister Jr.;

published by Wiley, Chichester, West Sussex, 1985; 602 pp.; price,£ 40.40.

Rack, H.J. and Qazi, J.I., 2006. Titanium alloys for biomedical applications. Materials Science and

Engineering: C, 26(8), pp.1269-1277.



Evaluate a Novel Top Surface Analysis Method to Determine the Mode I

Fracture Toughness of Materials and Interfaces

Shalini Priyaa SIDDHARTHAN

Supervisor: A/Prof Martin Veidt

The use of composite materials in the engineering sector has been increasing over the years. To

achieve good structural design, fracture toughness is one of the most important mechanical

properties. The primary aim of this project is to compare the conventional method of determining

Mode I fracture toughness to a Top Surface Analysis (TSA) method. PMMA Acrylic and Glass Fibre

Composite (GFC) interfaces are the main focus in this thesis.

Traditionally, the Double Cantilever Beam (DCB) method is being used. However, it does have its

limitations, which reduces the accuracies of the final results. Therefore, UQ created another form of

testing also known as TSA method, to determine fracture toughness. This method uses Digital Image

Correlation (DIC), which is advantageous when thin-walled structures are being tested on especially,

as data is not determined from the side-view, but rather from the top.

Both acrylic and GFC samples were divided into two different groups, each having four-five

specimens per group with varying widths. The heights and thickness of the samples were kept

constant at 25mm and 10mm respectively. M.R Ayatollahi et al. (2016) suggests acrylic samples

having a width of 150mm for the first group and 90mm for the second. GFC samples, however, is

proposed to have a width of 145mm and 180mm respectively.

Before testing, samples underwent pre-cracking. However, unexpected issues arose during this

process for acrylic samples and even after trying multiple other methods, a straight pre-crack could

not be formed. This was deduced to most likely cause a chip-off in the later part of the tensile testing,

if proceeded, and thus the focus of the project was then shifted to GFC reinforced laminates. GFC

samples first underwent pre-preg lay up; with a sheet in between the stacked ply layers. This formed

the pre-crack. The plate was vacuumed sealed subsequently. Water-jet cutting was then used to cut

the plate into the proposed dimensions.

DCB tensile tests are carried out using a constant-displacement rate device with a fixed load cell.

The data obtained will be noted and synchronized with the DIC software to provide TSA

measurements (ASTM D5528-01, 2001). In this stage of the project, the GFC samples have not yet

underwent testing. However, it is expected to have a fracture toughness value range between 110-150

J/m2 as investigated by Ye zhu (2009) for all batches of samples.

REFERENCES

ASTM D5528-01, 2001, Standard Test Method for Mode I Interlaminar Fracture Toughness of

Unidirectional Fiber-Reinforced Polymer Matrix Composites

M.R Ayatollahi, M. Rashidi Moghaddam, S.M.J Razavi, F.Berto, 2016, Geometry effects on fracture

trajectory of PMMA samples under pure mode I loading

Ye zhu, 2009, Characterisation of Interlaminar Fracture Toughness of a Carbon/Epoxy Composite

Material, The Pennsylvania State University



Understanding the Nexus between Abrasion Resistance and Fracture Toughness

in Ceramics — Ball Mill Abrasion Test and Ball Mill Edge Chipping Test

Rugeshrajah SELVARAJAH


Ore chute linings in the mining industry use ceramics such as alumina, zirconia toughened alumina

and basalt. The ceramic tiles on the surface of the chutes are subject to wear due to material flow.

When the cost effectiveness is examined, alumina and basalt gave a higher life per cost ratio in

comparison with other materials in a coal plant (Mutton, et al., 1988). Low-stress sliding abrasion

which is caused by material flow with low-impingement angles in chute lining is commonly

evaluated using Dry-Sand Rubber Wheel Abrasion Test (Gates, 2003). However, in industrial

conditions, other wear modes are also present. In this thesis project, the performance of the ceramic

tiles is investigated by evaluating the abrasion resistance and fracture resistance under wear modes

simulated using a ball mill. The ball mill tests involved are developed and used by UQ Material

Performance (UQMP).

As previous work on Ball Mill Abrasion Test focused on metal specimens, the performance of

ceramics is of interest. Alumina, Yttria – Tetragonal Zirconia Polycrystal (3Y-TZP) and Magnesia

Partially Stabilised Zirconia (Mg-PSZ) specimens were tested. Metal specimens were included as

reference materials along with the ceramic specimens and were held in a cassette that fits inside a

600mm laboratory ball mill. The mill charge consisted of quartz as the abrasives, rubber balls as the

grinding media and water to fill the interstices. The ball mill was operated at 50% of its critical

speed. The wear mode intended in the BMAT is low-stress sliding abrasion as the tangential sliding

of the quartz abrasives were dominant over the impact from the rubber balls. Notably, there were

minimal crushing of the abrasives which is usually the case in this wear mode. The abrasion

resistance of different materials was distinguishable from the results. Ceramic specimens had smaller

wear rates than metals. 3Y-TZP had the highest abrasion resistance among ceramics under low-stress

sliding abrasion in the ball mill.

The Ball Mill Edge Chipping Test was developed to assess the relative fracture resistance of

materials using the edge-chipping phenomenon of block specimens with sharp edges. From previous

work on BMECT, the test produced fracture resistance data with good statistical scatter and

reproducibility for metal specimens (Keen, 2012). Therefore, technique development of BMECT for

ceramics specimens is also an aim of this thesis project. Two different grades of alumina tiles were

tested in the ball mill to produce edge chipping by tumbling them with metal balls as the media. The

resulting mass loss of the specimens were evaluated to determine the relative fracture resistance.

Based on this fracture resistance data, the different grades of alumina tiles could be differentiated.

REFERENCES

Gates, J. 2003, Wear plate and materials selection for sliding abrasion, Australian Journal of

Mining, 184(16), pp. 28-32.

Keen, L. 2012, Effect of Tempering on Abrasion and Chipping of White Irons, Bachelor of

Engineering Thesis, University of Queensland.

Mutton, P. J., Macdonald, A. & Sinclair, W. 1988, Abrasion Resistant Materials for the Australian

Minerals Industry, Australian Minerals Industry Research Association Limited.



(G66) Understanding the Nexus between Abrasion Resistance and Fracture

Toughness in Ceramics – IC-SBAT and IC-CPAT

Sam WILSON


Wear is a fundamental part of the all materials and components. Within the mining industry wear

becomes a critical factor of the performance. Increasing the life of a component will reduce the

downtime of the machine and thereby improve productivity.

Ceramic materials have desirable properties which make them highly applicable for wear-protection

of typical mining and mineral operations Medvedovski, E. (2001). Ceramics provide an improved

wear performance, flow efficiency, noise control as well as an overall lower total cost in application

cme. (2017). However, companies are always striving to better understand as to why certain

materials will wear at a higher rate than others ad how to use this information to implement the most

efficient design for the component.

Primary factors which affect a materials wear resistance are the operating conditions as well as the

material properties Kato, K. (2002). Therefore, the abrasive wear resistance and in turn the wear

mechanisms can be evaluated from investigating how these factors affect the material and determine

the governing correlations.

In turn, the underlying damage mechanisms for a range of ceramics will be investigated in order to

conclude whether these materials operate in pure abrasive wear or if there are other factors involved

in the material wear. This will be examined through experimental testing of both ceramics and metal

samples.

These experiments will include testing both the standardised Rubber Wheel Abrasion Test (RWAT)

as well as the Inner-Circumference Sliding-Bed Abrasion Test. These tests will place the specimens

in real world applications where the material is undergoing operation where direct wear will occur.

Following the completion of this testing, the data will be collected and analysed, these results will be

compared to other properties of the materials such as fracture toughness, hardness, density and

microstructure. In turn, attempting to determine a relationship as to which properties and ultimately

which materials will be best suited to certain applications within the mining industry.

REFERENCES

cme. (2017). Ceramic Wear Liners - Crushing & Mining

Equipment. Crushingandminingcomau.ds.dashdigi.com. Retrieved 9 September 2017, from

http://crushingandminingcomau.ds.dashdigi.com/products/wear-products/ceramic-liners.html

Kato, K. and Adachi, K. (2002). Wear of advanced ceramics. Wear, 253(11-12), pp.1097-1104.

Medvedovski, E. (2001). Wear-resistant engineering ceramics. Wear, 249(9), pp.821-828.

http://crushingandminingcomau.ds.dashdigi.com/products/wear-products/ceramic-liners.html



The Influence of Process Parameters on Surface Roughness, Micro-Structure and

Mechanical Properties of Thinned-Walled Alumina Using Laser Engineered Net

Shaping (LENS)

Wei Feng TYE

Supervisor: Prof Han Huang

Additive manufacturing has benefits over traditional manufacturing: Speed, cost, quality and

innovation. One example is the use of rapid prototyping. Rapid prototyping enables companies to

reduce the end product’s time to market and reduce the cost of product development. Rapid

manufacturing allows for complicated products to be manufactured at low cost and production of

finished components (Attaran, 2017).

Currently, there is a demand for rapid manufactured ceramic products in various engineering

industries. These industries include automotive, aerospace, electronics, machine tools and medical

implants. This is due to their superior properties such as low density, high temperature strength,

hardness and greater tribological behaviours. For ceramics there are two kinds of additive

manufacturing methods, the indirect method and direct method. (Li, 2017)

In this project, thin-walled samples of Alumina and Alumina-yitteria was created via an Optomec

LENS 450 system, a direct laser deposition(DLD) additive manufacturing 3D printer. The use of

LENS is a direct additive manufacturing method. The main goal of the project is to understand the

relationship between the operating parameters, such as laser power, scan speed and powder feed rate

in the LENS system and the resultant properties.

REFERENCES

Attaran, M. (2017). The rise of 3-D printing: The advantages of additive manufacturing over

traditional manufacturing. Business Horizons, 60(5), 677-688.

Li, Hu, Cong, Zhi, & Guo. (2017). Additive manufacturing of alumina using laser engineered net

shaping: Effects of deposition variables. Ceramics International, 43(10), 7768-7775.


SYNOPSES C1: Batteries 1

Increasing the Sulfur Loading in a Lithium-Sulfur Battery

Ashley Abinash ANTHONY

Supervisor: Dr Ruth Knibbe

The increasing usage of batteries in the world has seen to be increasing in the past decade or so. This

has caused for a demand in higher powered battery cells to power electronic devices like phones,

laptops, electric vehicles and even small scaled grid networks. Lithium ion battery has manage to

provide the supply for this demand but researchers have been searching for an alternative source

where in this case lithium sulfur batteries has caught the attention of the energy industry around the

world. Lithium sulfur batteries are said to have a higher energy density and lower cost to

manufacture compared to the conventional lithium ion batteries. According to Hagen et al (2015), the

lithium sulfur battery is said to produce a load of 1672 mAh/g.

Despite the benefits in the Li-S cells compared to the commercialised Li ion batteries, there are

severalmsetbacks that inhibit the industrial usage of lithium sulfur batteries in our daily life

activities. The low sulfur loadings caused by the sulfur and reduced products which are non-

conductive reactants in of the reaction in which it causes the energy density of the cell to decrease

(Zhang, 2012). Another challenge is the redox shuttle of polysulphide where undesirable reactions

occur between Li2Sn and Li negative electrode of the battery (Lacey et al 2015). The performance of

the battery can be enhanced by increasing the sulfur loading of the battery,

One way to increase the sulfur loading of the battery is by increasing the thickness of the electrode to

produce more active material mass per area of the cathode produced. This would increase the mass

of the battery but may have a great affect on the sulfur loading of the battery. Further research was

done on selected components of the battery where binder and active material carbon nanotubes

(CNTs) that were used for battery construction. The binder that was used as a control for the

experiments was the conventional poly (vinylidene difluoride) (PVdF). Sulfur loadings were then

increased by manipulating the sulfur content in the active material and concentration of PVdF used.

Despite the success in increasing the sulfur loading, several research papers have shown the higher

sulfur loading was achievable. According to Ling et al (2017), the water soluble binder, carrageenan

acts as a stabilizing agent for the redox shuttle of polysulphide. By using thermally activated iota and

kappa species of carrageenan, the sulfur loading is seen to increase double of the previous test matrix

used. By optimizing this water soluble binder and also the sulfur content in the active material, a

higher sulfur loading of batteries with better performances is believed to be achievable.

REFERENCES

Zhang, S. S. 2012, Liquid electrolyte lithium/sulfur battery: Fundamental chemistry, problems, and

solutions, Journal of Power Sources 231, 153-162.

Hagen, M., Hanselmann, D., Ahlbrecht, K., Maça, R., Gerber, D., & Tübke, J. 2015. Lithium–Sulfur

Cells: The Gap between the State-of-the-Art and the Requirements for High Energy Battery Cells.

Wiley Online Library, 1-11.

Lacey, M., Yalamanchili, A., Maibach, J., Tengstedt, C., Edstrom, K & Gray, D. B. 2015, The Li–S

battery: an investigation of redox shuttle and self-discharge behaviour with LiNO3- containing

electrolytes, RSC Advances, 3632-3641.

Ling, M., Zhang, L., Zheng, T., Feng, J., Guo, J., Mai, L. & Liua, G. (2017), Nucleophilic

substitution between polysulfides and binders unexpectedly stabilizing lithium sulfur battery, Science

Direct, 82-90.



Commercial Scale Recycling of Lithium Ion Batteries in Australia

Maxwell J. BUCKLEY


Growth in the small electronics, electric vehicle and home energy storage markets has resulted in an

exponential increase in demand for lithium ion batteries (LIBs). In Australia, it is expected that waste

LIB volumes will grow 40-fold from 3,340 tonnes in 2016 to 120,000 tonnes in 2035. This poses a

threat to the sustainability of LIB systems, particularly in Australia where existing and planned

recycling infrastructure is severely lacking (Xue Wang, 2014).

In anticipation of the potential waste issue outlined above, this project aims to propose an

economically and environmentally feasible, efficient and sustainable LIB recycling system for

implementation in Australia. In doing so, it will consider the following stages within the system:

1. Collection and sorting of batteries

2. Location and scale of recycling plant

3. Dismantling techniques

4. Metal or battery recovery techniques

5. Approach to satisfy relevant regulations

The project will ensure a quality system is proposed by evaluating both existing and novel recycling

techniques based on a set of weighted criteria with a focus on relevance to the Australian context.

Given the well-established nature of battery dismantling and recovery techniques, the primary focus

of the presentation will be to discuss the challenges posed by the Australian context in the areas of

collection management and scale of plant infrastructure. Importantly, the shift from small battery

household disposal to large volume vehicle, home and grid storage waste will also be considered. In

doing so, the presentation will offer an insight into project progress and the preliminary findings with

respect to potential solutions to these challenges.

REFERENCES

Xue Wang, C. B. (2014). Economies of scale for future lithium-ion battery recycling infrastructure. Resources

Conservation and Recycling, 53-62.



Lithium-Ion Battery Recycling

Blake DYKES


By the year 2020 it is predicted that the global market for Lithium-Ion (Li-ion) batteries is expected

to exceed $30 billion (Taiyou Research 2014). This exponential growth results largely from

advancing technologies providing superior power and superior capacity cells, allowing development

into large-scale applications. Presently Australia remains as one of many countries yet to provide an

available, proven technology for the recycling of secondary batteries. As portable handheld devices

continue to rise and innovative companies such as Tesla keep testing technological limits industry

wide further venturing into the electric vehicle (EV) market is inevitable. Thus, recycling has

become more of a necessity in this technological evolution.

As researched, the majority of consumer portable handheld devices – typically mobile phones and

tablets – contain of the lithium cobalt oxide formulation (LiCoO2) with an amalgamation of other

metals introduced to enhance various performance specifications. With cobalt so widely used as the

formulation of choice the need for recycling is made more prominent by the current political

instability in African nations, namely the Democratic Republic of Congo (DRC). This instability has

tremendous effects on global markets via the strong recommendation not to undertake business with

such countries from the United Nations. Thus, ensuring there is a strong economical and geopolitical

advantage to guaranteeing a solution is met.

To date many companies across the world have attempted to develop their own-patented recycling

techniques. Some rely solely on pyrometallurgical approaches, whilst others, such Umicore rely on a

combination of pyro and hydrometallurgical techniques. As such the presentation will provide an

insight into the experimental workings and procedures undertaken to create a streamline and efficient

hydrometallurgical process. This process will include and focus on providing a detailed analysis of

methods used in dismantling the batteries, the composition of each battery and how this was analysed

and an outline of the acid leaching methods and results uncovered thus far.

REFERENCES

Taiyou Research. "Asahi Kasei Corporation." 2014.

https://www.marketresearch.com/product/sample-8323376.pdf (accessed 10 9, 2017 ).



Degradation Mechanisms of Lithium-Ion Battery

Ahadhim Dary ISMAYA


Lithium-Ion batteries (LIBs) are the most widely used energy storage system for personal devices,

power tools, electric vehicle, and grid energy storage. The popularity of the LIBs is due to its high

performance and compact size. However, there is a factor that decelerates the advanced use of LIBs.

It is the degradation affecting the overall performance of the LIBs; e.g. cycle-life, ability to store

energy, and limiting the ability to supply power demands.

Several studies have been conducted in the past relating to the degradation in LIBs. According to

Birkl et al., the main effect of the degradation that occur in LIBs are categorize into three loss modes,

which is loss of lithium inventory, active material of the negative electrodes, and active material of

the positive electrodes. Based on the loss modes that explained, there are two main effect of

degradation that occur, whether it is a capacity fade or power fade. In other studies, Broussely et al.,

studied that the degradation in LIB occurring either at rest or during cycling. Degradation on cycling

is mainly due to degradation of active materials. Degradation on rest will only depends on

thermodynamically stability of the battery components.

These days, LIBs as the energy storage system of many electric vehicles and the increasing use of

electric vehicle (EV), studies on the degradation in LIB system become an interesting topic. LIB

durability is a major importance for EV in order to deliver required performance and economic

aspect to the user for long period of time. In the EV, battery is the most expensive component and

yet the most sensitive component to fail. Most vehicles in general have a nature to use in all sort of

everyday use, whether it is hot in summer or cold in winter. The LIB in electric vehicle will easily

exposed to its environment, and this exposure can affect the installed LIB in the electric vehicle that

leads to degradation.

REFERENCES

Birkl, C. R., Roberts, M. R., McTurk, E., Bruce, P. G. & Howey, D. A. 2017. Degradation

Diagnostics For Lithium Ion Cells. Journal Of Power Sources, 341, 373-386.

Broussely, M., Biensan, P., Bonhomme, F., Blanchard, P., Herreyre, S., Nechev, K. & Staniewicz, R.

J. 2005. Main Aging Mechanisms In Li Ion Batteries. Journal Of Power Sources, 146, 90-96.



Lithium Ion Battery Recycling

Mario A. TORRES


Battery recycling has become a major issue in Australia. Currently, most of the potentially recycled

Lithium-ion batteries (LIB) are deposited into landfills or sent in bulk overseas (Lewis, 2010). This

represents a critical concern for the Australian Government and the National Waste Policy stablished

in 2009 as the emissions from these landfills contribute significantly to the greenhouse effect and

many of the compounds used to make batteries are a finite and expensive resource (Lewis, 2010).

In Europe, many efforts have been put into the recycling of batteries. In 2002, Belgium and Germany

recycled about 59 and 32 percent of their wasted batteries, respectively (Sangani, 2011). However,

more research needs to be carried into the recycling of LIBs as current trends predict an increase on

the demand of this type of batteries. Nowadays, Li-ion batteries are widely used in the

communication and automotive industries and their usage is increasing over time due to their

rechargeability and their high energy density compared to other similar technologies (Lewis, 2010).

Hydrometallurgical and pyrometallurgical process are used to recycle the different types of batteries.

And most valuable materials that can be extracted from LIBs are nickel, cobalt, lithium, and copper,

with cobalt and lithium as the most expensive (Chagnes, A. & Pospiech, B., 2013). Many companies

are currently investing on the recycling of LIBs and so, many commercial processes currently in use

to recover this type of batteries have been created, such as Toxco, Umicore or Recupyl processes.

A thorough investigation on Li-ion battery recycling has been carried out, where a comparison of the

commercial methods has been done, and so, a hydrometallurgical method that used sulphuric and

hydrochloric acid as the main leaching reactants was implemented in a laboratory facility at the

University of Queensland to then create a new LIB capable of display relevant electrical properties

that characterize a LIB.

REFERENCES

Lewis, H. 2010, Battery Waste and Recycling, Control Publications Pty Ltd, Victoria.

Sangani, K., 2011. Battery recycling. Engineering & Technology, 6(12), pp.53–55.

Chagnes, A. & Pospiech, B., 2013. A brief review on hydrometallurgical technologies for recycling

spent lithium‐ ion batteries. Journal of Chemical Technology & Biotechnology, 88(7), pp.1191–

1199.



The Degradation of Lithium-Sulfur Battery

Lianbang KOU


With the development of battery and technology, there is an increasing need on the capacity of

portable devices, meanwhile, the high demand of new energy automobile market makes more

requirements on battery performance. Since the new lithium-sulfur battery (LSB) has more

theoretical capacity (1675mAh g-1) and energy density (2600Wh kg-1) than traditional lithium-ion

batteries (3-5 folder), the research of LSB has become a new direction for the further development of

batteries (Zhang J, 2016). However, what cannot be ignored is within the process of LSB laboratory

research, as the reaction mechanism of the battery itself and the reason of the physicochemical

properties of sulfur, which cannot meet the theoretical value and makes the battery capacity and

energy density cannot fully replace traditional lithium battery. And this presentation is mainly focus

on the degradation of LSB and its influencing factors.

Within the electrochemical reaction of LSB, due to the low cost of sulfur, which has been widely

used as the cathode in the LSB, and the main reduction reaction of sulfur in the discharging process

is S8→Li2S8→Li2S6→Li2S4→Li2S2→Li2S (Ma L, 2015), however, with the low conductivity of

sulfur, it is necessary to add the conductive materials (such as CNT) in the cathode. Moreover, with

the intermediate product lithium polysulfide (PS) in the electrolyte of LSB, the Li/S cell cannot fully

react and achieve the theory battery energy. Meanwhile, as the form of solid electrolyte interphase

(SEI), which is non-conductivity and could resulting to the poor battery performance during the

discharging process (Ma L, 2015). This research is related to two factors which affecting the

degradation of LSB: cut-off voltage and discharge C-rate (which related to how fast the battery

discharges). The main structure of LSB is mainly composed of sulfur and conductive carbon with the

binder on the Al foil as the cathode, while the anode is made of lithium elemental and filling by the

battery electrolyte in them, and the main purpose of separator is to limit the LSB in the reaction

process of intermediate lithium polysulfide (PS) caused by the shuffle effect. As the serious of these

issues within the LSB, which could be leading to the self-discharging of the battery and the reduction

of battery cycling time and performance. All of these problems should be taken seriously before the

large-scale commercial use of LSB.

In my presentation I will discuss the factors of cut-off voltage and discharge C-rate related to the

degradation of LSB and the shuttle effect caused by the PS in the battery electrolyte.

REFERENCES Ma L, H. K. E. W. S. e. a., 2015. Nanomaterials: Science and applications in the lithium–sulfur

battery. 10(3): 315-338 ed. s.l.:Nano Today.

Zhang J, H. H. L. Z. e. a., 2016. Double‐Shelled Nanocages with Cobalt Hydroxide Inner Shell and

Layered Double Hydroxides Outer Shell as High‐Efficiency Polysulfide Mediator for Lithium–Sulfur

Batteries. 55(12): 3982-3986 ed. s.l.:Angewandte Chemie International Edition.



The Grain Size of Sulfur in Cathode of Lithium-Sulfur Battery Influence the

Battery’s Performance

Jiechen GAN (44829465)


In recent years, the demand for energy has huge increasing, especially in electricity. Therefore, all

the rechargeable batteries market has its own potential. (C. Pillot 2013) Lithium(Li) ion battery has

the most demanding in the market because of the high specific energy density. Lithium-Sulfur

battery (LSB) has the highest specific energy capacity in all Li-ion batteries categorize. (Wang

Hongqiang 2016) Thus, LSB has its potential in the future market and it became a promising

research project. However, there are still a lot of challenges need to face for LSB. For the cathode,

one of the main issues is that Sulfur is non-conductive material and its influence the performance of

the battery which gives high electric resistance. Weihong Chen (Hongwei Chen 2014) suggest that

decrease the grain size of Sulfur in the cathode of LSB can achieving a promising result for batteries

performance due to large exposed the surface of Sulfur doing the electric chemical reaction in

batteries. To find the relationship between grain size of Sulfur in the cathode and its battery

performance is the main purpose of this project.

Before starting the main project, there are several goals need to achieve. First, the electric chemical

reaction of LSB needs to understand both in principle and mechanism. Then, the basic batteries parts

which include cathode, anode, separator and electrolyte are fully well knowledge. Finally, practicing

synthesis cathode with 60% Sulfur and 40% carbon-nanotube (CNT 60) and batteries’ assembling.

According to Hongwei Chen (Hongwei Chen 2014), one of the cheap and convenient ways to

produce the smaller grain size of Sulfur in CNT 60 is using ball milling method. The method also

shows as the longer length of the time the smaller grain size of Sulfur. Thereby, 5 groups of LSB are

tested which are 0 hours, 3 hours, 6 hours,12 hours, 24hours of ball-milling for CNT60. The size of

Sulfur’s grain from different are measured in cathode microstructure by using scanning electron

microscope (SEM). After that, the batteries are assembled for impedance test (resistance test) and

cycling test (charge/discharge performance test). Using the collected data plot the impedance testing

curve and voltage performance curve in charge and discharge.

As the conclusion, the result seems promising. The grain size of Sulfur in the cathode will give the

reverse proportional quality of batteries’ performance. However, the error can be made during the

experience, each group the number of battery is not enough to provide highly promising results

which can decrease the random error. Furthermore, the gain size difference of Sulfur in cathode

CNT60 between 12h and 24 h in microstructure is very small, which may lead the testing data have

not produced a huge difference in these two groups.

REFERENCES

[1] C. Pillot. “The worldwide battery market”, Conference proceeding of International battery

seminar and exhibit, Nice, France, October 2013.

[2] Wang, Hongqiang, Design and modification of cathode materials for high-performance lithium-

sulfur and lithium-selenium batteries, Doctor of Philosophy thesis, Institute for Superconducting and

Electronic Materials, University of Wollongong, 2016. http://ro.uow.edu.au/theses/4839

[3] Hongwei Chen, "Monodispersed Sulfur Nanoparticles for Lithium-Sulfur Batteries with

Theoretical Performance", i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO),

Chinese Academy of Sciences, Suzhou 215123, China. 2014


SYNOPSES D1: Mechanical 1

CFD Validation of Centrifugal Compressor Performance

Wei Sheng CHUANG

Supervisor: Dr Ingo Jahn

The University of Queensland Turbomachinery and Power Conversion Group is currently

developing a device to apply resistive load to turbine shaft in order to test the turbine. Previous

studies proposed the use of a centrifugal compressor, design to dissipate at 100 kilowatts, at shaft

speed 120,000 revolution per minute (RPM). The primary goal of this thesis is to verify the

capability of an aerodynamic centrifugal compressor in meeting the standards of a proposed

geometry based on the use of Computational Fluid Dynamic (CFD) simulations.

The verification of the simulation required appropriate assumptions made throughout the

development of CFD. The proposed geometry covered the key details of the impeller. Appropriate

assumptions were made on blade height and blade flow profile to resemble many commercially

available blade geometries. ANSYS CFX acted as the CFD solver. Each geometry was meshed

independently and expressed as a different domain in CFD solver. The compressor system was

modelled at a steady-state and ideal air gas condition, within adiabatic wall. To reduced

computational cost, only single passage was considered. In addition, only single speed line was

considered at this stage to verified performance of the preliminary centrifugal compressor.

Initial results however, indicated an over prediction of the design pressure ratio, resulting in the

choking of the compressor. This was shown in CFD flow field analysis through a high Mach number

around the leading edge of the blade. Viscous losses in the impeller were captured by the CFD which

was not accounted for in the previous prediction. In summary, a compressor map and efficiency

contour plot from CFD simulation would increase the confidence of the designs ability to meet the

requirements.



A New Perspective of Lithic Reduction in Archaeology: Numerically Simulating

Flintknapping with Peridynamics

Matthew P.W. DAY


Stone artefacts have been manufactured and used in a variety of tool forms by humans for

approximately 99% of our history. Given their durability and typical abundance, stone artefacts

represent one of the most important records of our past human and hominin ancestor’s activities.

The study of lithic reduction (the sequence of chipping a piece of material to create a desired shape)

in archaeology allows for interpretations of the past to be made.

Within experimental archaeology, lithic analysis aims to understand the behavioural and physical

factors associated with stone tool manufacture. Researchers attempt to understand both why and how

someone in the past made particular stone tool forms. One form of analysis consists of controlled,

simplified experiments, which mechanically simulate the flintknapping process. Through such

experiments researchers attempt to find causal relationships between select input variables and the

observable morphological features of a flake. Understanding which parameters (or combination of)

are responsible for particular morphological features on a stone flake would lead to a greatly

improved understanding of human and hominin behaviour in the past.

Although controlled experiments have the potential to improve our understanding of which

parameters control flake morphology, no conclusive results have yet been reported. Few experiments

have been conducted, in part due to their time-consuming nature, lack of repeatability, cost and

issues of variability.

Utilising an innovative development in numerical simulation, this research project considers lithic

reduction from a new perspective. The recently formulated mathematical theory of peridynamics

(Silling 2000) enables the simulation of crack initiation and propagation, whilst avoiding the

common shortcomings of more traditional methods such as the extended Finite Element Method

(XFEM).

Through the use of peridynamics it has been possible to simulate important morphological features

observed in flintknapping, such as partial Hertzian cone cracks. To verify the accuracy of the

simulations in LS-DYNA, simulation results are compared against analytical descriptions of Hertzian

stress fields. Following the verification of the results, several existing hypotheses produced from

archaeological controlled experiments will be tested. These tests will assess whether perceived

relationships between variables such as the external platform angle (EPA) and flake length are

supported by numerical simulation.

REFERENCES

Clarkson, C & O’Connor, S 2014, ‘An Introduction to Stone Artifact Analysis’, in A Balme (ed),

Archaeology in Practice: A Student Guide to Archaeological analyses, John Wiley & Sons, Inc. pp.

151-206.

Silling, SA, Reformulation of elasticity theory for discontinuities and long-range forces. Journal of

Mechanics and Physics of Solids, vol. 48, pp. 175-209.



Top Surface Analysis Measurement Techniques for Mixed Mode and Mode II

Fracture Toughness Values of Materials and Interfaces

Shane. N. EVANS

Supervisor: A/Prof Martin Veidt

Material interfaces are of great interest to industrial and aerospace design as they can significantly

increase a materials toughness properties. However, assessing the failure at interfaces is difficult and

requires experimental procedures and/or computational software abilities. It is well documented that

interfaces are susceptible to premature failure by adhesive debonding. This therefore raises the issue

for reliable methods to capture the information accurately.

The traditional experimental method to capture the toughness properties of the interface involves the

conventional side view procedure, which heavily relies upon the optical tracking of the crack front

under loading. Therefore, a recently developed method that is capable of circumventing the

complexities associated in experimental tests is the Top Surface Analysis (TSA) used in conjunction

with Digital Image Correlation (Reiner et. al 2017).

Top Surface Analysis is the method which predominately focuses on the top surface of the specimen

with Digital Image Correlation (DIC) being the method which captures the information. Therefore,

the TSA is to be developed further to determine if it can effectively capture mixed mode and mode II

fracture properties. This has led to a Literature Review to determine the most reliable experimental

procedure, material specimens and Finite Element Analysis (FEA) solvers.

The material and interface tested involves a Fibre Metal Laminate (FML), made up of Glass Fibre

Reinforced Polymer (GFRP) and steel and is tested at two specific geometries in order to capture the

identified fracture modes. The test procedure chosen involves the Double Cantilever Beam (DCB),

the procedure which involves pulling apart the specimen at the selected edge which includes a pre-

crack between the interface of the GFRP-steel. Finally, the Virtual Crack Closure Technique

(VCCT) has been selected for stress comparisons experienced at the crack front and in each

respective material substrate.

For comparison, a ‘pure’ mode I scenario is first evaluated and compared to the conventional side

view method and FEA solver before carrying out the mixed mode scenario. This allows a

quantifiable comparison between the two tests for whether TSA has captured mode II and to identify

areas of limitation.

Numerous advantages have been identified in comparison with the conventional side view method,

particularly by limiting the required skillset of the operator. Furthermore, it is possible to identify

modal fracture properties at the crack front, an ability which has only been capable in prior FEM

studies (Reiner et. al 2017).

REFERENCES

Reiner, J. T, P Juan & Veid, M 2017, A novel Top Surface Analysis method for mode I interface

characterisation using Digital Image Correlation, Engineering Fracture Mechanics, 173:107-117

ISSN 0013-7944.



Flexural Fatigue Properties of a 3D Printed Polymer for use in Orthotic Insoles

Mark J. FITZPATRICK

Supervisor: Dr Gui Wang

Additive manufacturing has rapidly transitioned from a useful prototyping tool to a viable

manufacturing method in many applications. The technology has advanced significantly, allowing

stronger parts to be made from a greater variety of materials in a faster printing time. To this end, a

local podiatry company has purchased a high-end selective laser sintering (SLS) device to use 3D

printing technology to manufacture orthotic insoles.

This project set out to examine the fatigue properties of the nylon polymer used in the insoles, to

assess the suitability of the new method to the particular application. This is especially important in

orthotic devices which rely on specific geometries, precise to the millimetre to enact change in the

patient’s posture and/or gait. However, the literature shows that over a large number of cycles,

polymers exhibit fatigue through the mechanism of stiffness degradation (Ziemian, et al., 2016;

Sauer & Richardson, 1980). This leads to greater changes in geometry and potentially less benefit in

using the orthotics. As such, this investigation aimed to provide a greater understanding of the

functional life of the new devices.

To test the fatigue characteristics of the polymer the ASTM-D7774 standard has been employed.

This dictates the testing method for the flexural fatigue of plastics and involves a three-point bending

setup clamped at the top and bottom surface of the specimen. A compatible mounting rig was

designed and constructed for use with the Instron A-591 hydraulic actuator in the UQ Materials

Testing Laboratory.

Three different materials are being tested: a fused deposition modelled (FDM) nylon sample (as a

control), a milled nylon sample (representing the existing orthotic material and manufacturing

method) and a SLS nylon sample (from the printer used by the podiatry company). Testing is still

ongoing, with present results showing a clear fatigue limit of 24 MPa in the FDM specimens. This is

an order of magnitude more than the 280 kPa found to be the worst-case estimate of the stresses

generated while running (Lemmon, et al., 1997). As such, if the further testing follows this same

trend it will suggest that 3D printed orthotic insoles do indeed possess the necessary fatigue

properties to be suitable for their application.

REFERENCES

Lemmon, D. et al., 1997. The Effect of Insoles in Therapeutic Footwear - A Finite Element

Approach. Journal of Biomechanics, 30(6), pp. 615-620.

Sauer, J. & Richardson, G., 1980. Fatigue of Polymers. International Journal of Fracture, 16(6), pp.

499-532.

Ziemian, C., Ziemian, R. & Haile, K., 2016. Characterization of stiffness degradation caused by

fatigue damage of additive manufactured parts. Materials & Design, Volume 109, pp. 209-218.



Development of High Performance Cycling Shoes Using Advanced Composite

Materials

Alex M. GRUNKE

Supervisor: Dr M. HEITZMANN

This thesis explores the development of a custom made cycling shoe to be used in high-performance road and

track cycling. The type of product being developed is not currently available to the market and would offer an

advantage to high-performance (HP) athletes. The custom cycling shoe is designed to be manufactured in

small quantities, the aim of the product is to provide the most efficient shoe to the customer as is reasonably

possible. Members of the Australian HP track team have been consulted to test this product and to gauge it’s

need in the sport. Cycling Australia has adjusted its budget to support the track team for the Commonwealth

and Olympic Games after expectations were not met at Rio in 2016. “With limited resources, to improve we

have to refine and focus operations, improve efficiency, and strategically invest using evidence that is aligned

to the proven principles of high performance” (Jones. S, 2017, Cycling Australia).

During the development of this product there were three key subsections that were considered. These include;

the mechanical goals of the product, the materials and manufacturing process and the optimisation of fibre

layup. A form of rapid prototyping was used to develop the design and manufacturing techniques. After

consultation with HP cyclists and podiatrists it was concluded that there were four major goals for the product

for it to be able to capture the HP cycling market. The shoe needs to be stiff for maximum power transfer from

the rider to the pedal of the bike, light as to minimise wasted energy. Aerodynamic, particularly for the HP

track cycling market, and comfortable. It was concluded that a combination of unidirectional and twill weave

SE84LV Carbon Fibre Epoxy prepreg system be used, alongside a NOMEX OX aramid honeycomb core and

plain weave aramid fabric paired with an epoxy LY3600CL system. These materials provide the desired

mechanical properties, comply with the proposed manufacturing process of the custom shoe and are available

in Australia. Manufacturing “one-off” HP parts can be costly; the development of this product and its

manufacturing process has considered this. The proposed manufacturing method involves seven major steps.

These include, moulding the feet and modifying them to maximise the biomechanical efficiency and comfort

of the shoe, layup of the materials to form a shell and a separate tongue, curing utilising a vacuum bag

process. Then dry aramid weave is wet laminated to the cured prepreg shells, before post curing the entire

shoe. Finishing and the addition of fittings yield the final product. A simulation software (ANSYS) is also

used to optimise the design of the product. This involves performing an optimisation to minimise deformation

of the shoe using minimal materials and to minimise any ply failure. A CFD analysis will also be performed to

test the aerodynamic properties of the shoe. Three HP athletes have been used in this process to test and

evaluate the product. They will perform six testing protocols to determine the efficiency of the shoe in

comparison to major competitors. They will also complete a survey after each day of use over a week of

training to evaluate the comfort of the product.

The development of this HP cycling shoe has yielded a product optimised for efficiency in the sport. It has

also outlined a manufacturing process that produces small quantities of high quality shoes for a relatively low-

cost with an estimated outlay of $70 in composite materials and non-reusable items for each pair, with

minimal tooling and equipment required.

REFERENCES

Jones. S & Finch-Penninger.J, 2017, Is Cycling Australia’s Focus the right one?,

https://www.sbs.com.au/cyclingcentral/article/2017/10/16/cycling-australias-focus-right-one

https://www.sbs.com.au/cyclingcentral/article/2017/10/16/cycling-australias-focus-right-one



Fire Whirls: Generation Mechanisms

Andre S. JARAMILLO

Supervisor: Reader A. Klimenko

Fire whirls are characterized by its rapid combustion rates and fast whirling velocities. This phenomenon

represents an important hazard to fire crews due to the increase of fire spotting. The most destructive fire

whirl took place in Japan after the Great Kanto Earthquake fire killing approximately 38,000 people (Chuah et

al., 2011). Even though fire whirls have been a matter of interest on previous years, the complexity of its

structure and the complications encountered at obtaining quantitative data on actual fire whirls due to safety

hazards, have kept this phenomenon poorly understood. The work presented here reviews the literature on fire

whirls, focused on the generation mechanisms, structure and governing processes.

Fire whirls are structured by swirling motion (vorticity) produced by the interaction of ambient air with

currents coming from a hot plume, and an upward conservative current (Soma and Saito, 1991). The

dynamics present on a fire whirl are generally similar to the ones encountered in other rotating structures

present in nature such as dust devils, tornados or hurricanes, as they require an ambient vorticity and

mechanisms to accumulate that vorticity into the whirl’s vortex core (Hartl, 2016). A vertical vortex line is

generated by the viscous shear forces produced at the ground and wind pressure force (Zhou et al., 2016).

These horizontal vortex line is the source of eddy flows that increase the flame height. Scaling laws are used

to predict the generation of fire whirls (Saito, 1998). Kuwana et al. (2008) introduced a scaling law using the

Freud number to calculate the critical lateral wind velocity that generates the most intense fire whirls. An

approximation of the flame height can be predicted by the burning rate and the circulation of the flow

(Kuwana et al., 2008). In an axisymmetric flow such as fire whirls, the tangential velocity (𝑼𝝑) increases

linearly with respect to the radius inside the fire whirl’s core; and decreases as 𝟏

𝒓 outside the whirl core (Hartl,

2016). These was confirmed by Hartl (2016) using Particle Image Velocimetry (PIV).

Fire whirls can be considered to be quasi-steady state when the mass loss rate from the fuel source is constant

(Wang et al., 2016). The tangential velocities at the inner and outer core con be estimated using the Rankine

vortex model and the circulation by the Burgers vortex approximation. The height from a fire whirl is

influenced by the radial density gradient, circulation and the air inflow at the whirl’s base. Circulation reduces

the supply of oxygen at the flame surface producing an elongation on the fire whirl to increase its surface are

to compensate this reduction of oxygen. (Hartl, 2016).

This review examined researches focused in the mechanisms present at fire whirls and the dynamic properties

involved in this phenomenon. It has been observed that numerical modelling requires further development

specifically for non-stationary off-source fire whirls.

REFERENCES

Chuah, K. H., Kuwana, K., Saito, K. & Williams, F. A. 2011. Inclined Fire Whirls. Proceedings Of The

Combustion Institute, 33, 2417-2424.

Hartl, K. 2016. Experimental Investigation Of Laboratory Fire Whirls. Doctor Of Philosophy, Princeton

University.

Kuwana, K., Sekimoto, K., Saito, K. & Williams, F. A. 2008. Scaling Fire Whirls. Fire Safety Journal, 43,

252-257.

Saito, K. 1998. Reconstruction Of Very Large-Scale Fires. Reconstruction Of Very Large-Scale Fires.

Soma, S. & Saito, K. 1991. Reconstruction Of Fire Whirls Using Scale Models. Combustion And Flame, 86,

269-284.

Wang, P., Liu, N., Hartl, K. & Smits, A. 2016. Measurement Of The Flow Field Of Fire Whirl. Fire

Technology, 52, 263-272.

Zhou, K., Liu, N. & Yuan, X. 2016. Effect Of Wind On Fire Whirl Over A Line Fire. Fire Technology, 52,

865-875.


SYNOPSES E1: Mining

Implications of Truck Dump Loading on Tip Head Stability

Boitumelo. GABOFELE

Supervisor: Dr Z. Chen

Slope stability problems will continue to exist as bigger waste dumps are constructed, therefore,

slope stability analysis is essential during design of dumps to minimize risk to human and equipment.

The need for slope analyses continue to increase which makes slope stability analysis a necessary

tool when designing waste dumps.

The project aims to identify geotechnical factors that affect dump slope stability and other factors

that accelerate dump slope instability, and identifying the impacts of truck loading on slope stability

by using numerical modelling to analyse the effect of dump geometry, geotechnical factors, and

loading conditions on slope stability. The results of RS2 and Slide will be compared to recommend

the suitability of the appropriate software to dump slope stability analysis.

The material parameters and external factors such as the dump geometry and loading factors affect

slope stability. The material parameters analysed are cohesion, unit weight and friction angle. The

FoS of the dump increases with increasing friction angle and cohesion. An increase in dump height

and slope angle reduces the safety factor. The safety factor increases as the berm size increases. The

analysis for loading on the dump shows a gradual decrease of safety factor as the load size is

increased. The results from both programs are affected by technical factors such as the stress

reduction factor and the type and number of elements for RS2 and the number of slip cycles and the

number of slices for the slide program. The RS2 results are more reliable than the Slide because RS2

which is a Finite Element Method (FEM) investigate the constitutive model and it also uses the shear

reduction technique.

BIBLIOGRAPHY

Behera, P, Sarkar, K, Singh, A, Verma, A, and Singh, T, 2016. Dump slope stability analysis – A

case study. Journal of the Geological Society of India, 88(6), 725-735. doi: 10.1007/s12594-016-

0540-4.

Hoek, E and Bray, J, 1977. Rock slope engineering. London: The Institution of Mining and

Metallurgy.


SYNOPSES E1: Mining

Blasting Near Sensitive Structures at the Mangoola Open Cut Mine

John BEATON

Supervisor: Dr Italo Onederra

Blasting is a necessary component of open cut coal mining, required to fragment and loosen waste

rock and coal to enable its efficient mechanical removal. It is considered however, that only 20 –

30% of the explosive energy is consumed by the breakage and movement of the material, with the

remainder of the energy lost as undesirable side effects, such as ground vibrations, air blast

(overpressure), noise and fly rock (Singh and Singh, 2005). Ground vibrations are of particular

concern to mining companies, due to its potential to damage nearby structures and cause nuisance to

people.

The Mangoola open cut coal mine, located in the Hunter Valley, NSW, operates within 50m of a

500kV high voltage power transmission line, the highest voltage that powerlines are operated in

NSW and therefore a critical piece of state infrastructure (Transgrid, 2018). Stringent blast generated

ground vibration limits are imposed by the state government regulator to protect the powerline

towers from damage. The vibration limitations, combined with a lack of confidence in predicting the

ground vibration generated by blasting has given rise to a very conservative blasting strategy when

blasting within 150m of the powerline which has resulted in considerable cost increases and

productivity losses to the blasting and mining operations. The project aims to develop a blasting

strategy that minimises these issues while still complying with the vibration limitations on the

powerline towers.

A review of the literature relating to blast generated ground vibration was undertaken, which

identified the various models, both empirical and computational, available to predict blast generated

ground vibration levels. Empirical models, provided they can provide acceptable prediction

accuracy, are shown to preferable to other models for use at Mangoola due to the simplicity to use,

instant prediction result, ease of calibration using regression analysis of site blast data and do not

require specialist personnel or computing power to setup and run.

Ten months of blast vibration data was analysed, which consisted of four vibration monitors at

separate powerline towers and vibration recordings from 82 individual blast events. Regression

analysis of this data using four empirical models was undertaken to first calibrate, then assess the

models for their accuracy in predicting vibration. For each of the four monitoring locations, the

USBM developed, AS2187.2 adopted equation was shown to give the most accurate vibration

prediction with coefficients of determination ranging from 0.81 to 0.94 indicating a very high

correlation of the model prediction to the measured data. Based on this model, rules for the

maximum designed charge mass at specific distances from the tower monitoring points will be

developed with an appropriate level of conservatism applied. These rules will then be tested in the

field, prior to being recommended as part of an updated blasting strategy for blasting near sensitive

structures.

BIBLIOGRAPHY

Singh, T N and Singh, V, 2005. An intelligent approach to prediction and control ground vibration in

mines, Geotechnical and Geological Engineering, 23(3):249-262.

Transgrid, 2018. Our assets [online]. Available from: < https://www.transgrid.com.au/ > [Accessed:

15 February 2018]


SYNOPSES E1: Mining

A Comparison of Visual Methods for Generating Digital Point Clouds

Russell WEBSTER

Supervisor: Dr C.R. Leonardi

The mining industry has historically been instrumental in the innovation and application of newly-

developed technologies. The economies of scale model that many mine sites enact, will benefit

greatly from even the smallest optimisation (Cehlár et al, 2017). Mining has seen many innovations

that has transformed the industries standard operating procedures throughout history. Photo-based

3D reconstruction methods becomes exceeding convenient, bordering on mandatory, because of the

ability to collect data from unsafe or inaccessible exposures (Bemis et al, 2014). Removing the field-

hand from the hazards associated from rocky-outcrops and sheer faces is highly-desirable in any

industry but more so in mining.

This desktop study has investigated various methods and strategies used to map terrestrial features in

a mining context. This involved reviewing and analysing a selection of highly-used methods in

industry today and then ranking each of their strength and weaknesses against each other. The focus

of this research project is to review the current technologies available for use in the mining industry

that are able to map terrestrial features using long-range visual methods to further generate point-

cloud data.

During the mapping process, key sources of error were identified relevant to a mine-site context.

These errors were categorised and investigated in order to determine ways to mitigate any distortion

that should be introduced. Of these errors, it was found that the systematic group of errors could

introduce widescale error that was difficult to validate once captured (James Mike and Robson,

2014). Correct workflows during the data acquisition phase was the strongest counter to these types

of errors. It was also found that the convergence of technologies is playing a major role in the

development of new models and the associated level of confidence (Turner et al, 2014).

BIBLIOGRAPHY

Bemis, S P, Micklethwaite, S, Turner, D, James, M R, Akciz, S, Thiele, S T and Bangash, H A,

2014. Ground-based and UAV-Based photogrammetry: A multi-scale, high-resolution mapping tool

for structural geology and paleoseismology, Journal of Structural Geology, 69:163-178.

Cehlár, M, Janočko, J, Demirel, N, Anyona, S, Vöth, S, Tyulenev, M and Zhironkin, S, 2017. From

Mining Innovations to Sustainable Development: Keynote Speakers of the First to the Second

International Innovative Mining Symposium, paper presented to E3S Web of Conferences.

James Mike, R and Robson, S, 2014. Mitigating systematic error in topographic models derived from

UAV and ground‐based image networks, Earth Surface Processes and Landforms, 39(10):1413-

1420.

Turner, D, Lucieer, A, Malenovský, Z, King, D H and Robinson, S A, 2014. Spatial co-registration

of ultra-high resolution visible, multispectral and thermal images acquired with a micro-UAV over

Antarctic moss beds, Remote Sensing, 6(5):4003-4024.


SYNOPSES E1: Mining

University of Queensland Experimental Mine Minewater Assessment

Cameron M STUBBINS

Supervisor: Dr B. White

The University Experimental Mine (UQEM) is a lead-silver mine that was operated between 1919

and 1929, before being donated to the University of Queensland in 1951 (Grubb, 2013). The UQEM

has since been used as a research and training centre for student engineers at the University of

Queensland (Grubb, 2013). The University of Queensland has undertaken site maintenance for the

lease area from 1951 onward, including both the above ground and underground sections. The

UQEM experiences an inflow of water into the underground workings which much be drained. The

quantity of water to be drained is large regardless of the rainfall experienced which begs the question

of the water source.

This project aims to determine a relationship between the rainfall and minewater discharge, to

estimate the void size of the UQEM and evaluate the effectiveness of capping the pit to redirect

rainwater from the pit. To complete these objectives, rainfall and dewatering data from the UQEM

will be analysed, and close attention will be paid to the 2011 Brisbane floods to determine the void

size.

Analysis of the 2011 Flood data shows that over one third of the total voids in the UQEM are located

beneath the pit floor. A pit cap for the UQEM is expected to save the equivalent of over two months

of minewater drainage per year. A combination of the GRAM and MIFIM minewater recharge

methods (Wolkersdorfer, 2008) was used to create an appropriate model for the UQEM. This model

was used in conjunction with the calculated UQEM pit area and the underground volume to find an

equation linking the rainfall and minewater discharge. These findings show that the majority of the

water inflow is through groundwater sources, likely the nearby Witton Creek.

REFERENCES

Grubb, K, 2013. Silver Hill: The University of Queensland Silver Mine Precinct. pp 4-8 (University

of Queensland: Brisbane)

Wolkersdorfer, C, 2008. Water Management at Abandoned Flooded Underground Mines. pp 37-105

(Springer Berlin Heidelberg)

http://link.springer.com.ezproxy.library.uq.edu.au/search?facet-creator=%22Dr.+rer.+nat.+Christian+Wolkersdorfer%22



Aluminium Plastic Deformation Limits for Incremental Sheet Forming

Jordan HODGES

Supervisor: Dr Bill Daniel

Incremental sheet forming is a metal forming technology growing in popularity in the aerospace

industry due to its flexibility compared to traditional die-based techniques. Incremental forming

limits are known to exceed expected thresholds due to complex loading however the extent to which

is poorly understood. This thesis investigated incremental forming limits under various states of

plastic strain for the aerospace grade 2024 and 7075 aluminium alloys.

Forming limits were investigated by using two dimensional specimens designed to approximate

plane strain and in-plane shear stress-strain states during plastic deformation. These testing

specimens were inspired by experiments conducted by Bjorklund (2014) with the stress-strain state

at plastic failure analysed using a combination of experimental testing and Finite Element Analysis.

The plane strain and in-plane shear stress-strain states were selected as compound states which could

be approximated using complex geometry on a single-axis tension test. Both states assume that strain

is distributed in two of the three axes according to the law of volume conservation, with the third

axis experiencing negligible deformation.

The finite element software initially struggled to resolve highly-plastic necking behaviour as

complete failure was approached. This meant model optimisations had to be made and a degree of

forward-projection used, informed by the experimental data. The experimental load-extension data

was used to calibrate plastic behaviour of the finite element model and hence infer the true stress-

strain state of the specimen’s centre at the onset of failure. Generally, it was found that finite element

model over-predicted plastic stiffness for the plane strain condition and under-predicted plastic

stiffness for the in-plane shear condition.

The formative limits obtained from this investigation apply to 2024 and 7075 alloys in the fully

annealed ‘O’ condition. It is recommended that alternative models are developed for the commonly

used T3 and T6 heat treatments, while future research could examine the impact of deformation path

dependence and cold work rolling direction.

REFERENCES

Bjorklund, O 2014. Failure characteristics of a dual-phase steel sheet, Journal of Materials

Processing Technology.



A Comparison between the Microstructure and the Mechanical Properties of

Pure Titanium and Biomedical Titanium Alloy

Amir Arsyad KHAIRUDDIN


Recent studies are concerned on the biocompatibility of titanium alloy for joint replacements and

dental implants. Existing Ti alloy such as Ti-6Al-4V alloy has been studied and Niobium (Nb) was

substituted with Vanadium (V) because V has toxic behaviour and show adverse tissue effects. Nb

acted as a passive element and does not tend to experience chemical breakdown inside the human

body (Long and Rack 1998). Nb is also found to be the least dense of refractory metals (Callahan

and Wolfenden 2005).

Due to research interest in Nb element in Ti , this study investigates β titanium alloy specifically Ti-

Nb alloy manufactured through powder metallurgy routes. The purpose of this study is to find out

which sample is the potential material for biomedical application by comparing Ti-Nb alloy with

pure titanium in terms of the microstructure and the mechanical properties. In this research, four

samples were prepared by powder metallurgy. They are pure titanium (Ti), Ti-10Nb, Ti-20Nb and

Ti-30Nb. Each sample was mixed in an attritor, compacted using uniaxial die pressing with

compacting pressure of 550MPa and sintered inside a tube furnace at 1350oC for 3 hours. The

samples were then mounted, grinded and polished before testing.

The microstructure for each samples were investigated using optical microscopy and the mechanical

properties were investigated by conducting compression tests. From metallography investigation,

increasing Nb content caused appearance of β-phase gradually between α plates. Beta grain

boundaries were also found to be more numerous and refined in the microstructure. During

compression test, each sample undergo plastic deformation and failure. From this test, a stress-strain

graph is obtained and analysed. It was discovered that Ti-20Nb sample has the lowest elastic

modulus.

REFERENCES

Long, M. & Rack, H. J. 1998. Titanium alloys in total joint replacement—a materials science

perspective. Biomaterials, 19, 1621-1639.

Callahan, B. P. & Wolfenden, R. 2005. CRC Handbook of Chemistry and Physics: A Ready-

Reference of Chemical and Physical Data, 85th ed.(Book Review).



Controlling the Microstructure of Titanium Alloys through Solidification

Processing

Jack L. KRYNEN

Supervisor: Dr M.J. Bermingham

Titanium alloys offer many highly attractive properties for aerospace and biomedical applications,

including high specific strength, excellent corrosion resistance and biocompatibility. Despite their

potential, the commercial application of titanium alloys is severely limited in comparison with

conventional structural metals. This is primarily attributed to their high material cost and the high

cost associated with traditional subtractive manufacturing processes. It is highly beneficial to

minimise the need for machining through development of effective near-net shape manufacturing

techniques for titanium alloys. The advancement of additive manufacturing (AM) technology for

titanium alloys promises to significantly reduce part costs through minimisation of material wastage

and processing times. Currently available AM technologies for titanium alloys involve the building

up of parts by consolidation of powder or wire feedstock in a layer-by-layer fashion through

localised melting and solidification. These processes involve relatively small melt pools, large

cooling rates, and highly directional heat extraction which is understood to favour epitaxial

nucleation, directional growth of β-Ti and the lack of nucleation events ahead of the solid-liquid

interface. Coarse columnar grains, with strong crystallographic texture are widely reported in AM

Ti-6Al-4V parts. The presence of textured grain structures imparts unfavourable mechanical property

anisotropy, which presents major challenges in the certification of AM titanium parts. Ideally it is

desirable to obtain homogeneous as-deposited microstructures consisting of refined equiaxed grains.

This relies upon promotion of the columnar-to-equiaxed (CET) which is influenced by factors

driving nucleation and growth of β-Ti during solidification. The purpose of this research is to

investigate the effects of thermal parameters within the melt pool (specifically temperature gradient

and growth rate) and alloy constitution on the enhancement of CET and grain refinement for AM of

titanium alloy parts. A wire and arc additive manufacturing (WAAM) cell was utilised for this study

as the melt pool is large enough to allow for reliable in situ measurement of cooling curves using

pyrometers while alloy chemistry can be easily changed. The cell consists of a gas tungsten arc

welding torch, wire feed system and local shielding unit installed within a build chamber with a

three-axis computer-numerical-controlled manipulator. Firstly, Ti-6Al-4V was selected as the

baseline alloy for this study since its solutes are known to provide negligible constitutional

undercooling and growth restriction. Ti-3Al-8V-6Cr-4Mo-4Zr (ASTM Grade 19) was selected since

it contains a significant weight percentage of solutes with high theoretical growth restriction factors

which are expected to provide sufficient constitutional undercooling in order to activate available

native nucleant particles. Finally, the addition of a rare-earth oxide powder was studied since it has

been identified as potentially thermodynamically stable within liquid titanium and therefore

hypothesised to enhance nucleation according to the free-growth model. By comparison between

experimentally determined thermal parameters with solidification maps for Ti-6Al-4V from

literature, it was determined that the inherent solidification conditions encountered during WAAM

are favourable for equiaxed solidification however columnar structures were consistently observed in

the as-deposited microstructure. Alloy design through addition of solute and nucleant particles

allowed for significant grain refinement, with grain size reductions of more than 83% observed.



Development of Test Methodology to Assess the High Temperature Corrosion of

Pre-Stressed Samples

Xe Jian LEE


Gasification can be referred to a chemical process that converts any carbonaceous fuel into gaseous

fuel (Hooshyar, 2016). The available oxygen in the biomass environment for the complete

conversion of hydrocarbon is deficient compared to combustion (Basu, 2010). and the resulting

gaseous products are dominated by species such as hydrogen and carbon monoxide. The presense of

other gas species includes water vapour, chlorides, sulphides, as well as fly ash or aerosols also

increase the severity of corrosion in biomass industry. This is often due to the difficulty in

developing the protective oxides on the steels components applied in these high temperature

environments. Therefore, it is of utmost importance to perform corrosion studies in biomass

gasification to improve our knowledge about the high temperature corrosion processes occuring in

the steels.

This thesis investigates the development of test methodology to examine the corrosion behaviour of

stainless steel grade 316 under loaded condition at high temperature. During final preparation,

precaution need to be taken to avoid excessive pressure on the test piece to prevent residual stress or

metallurgical changes that may induced in the surface. The suitable combination between

temperature and duration for testing is proposed to document the weight changes of the test piece in

order to calculate the corrosion rate. At the duration of testing, visual inspection on the surface of the

test piece is carried out to ensure the testing is terminated once the crack initiated. In this research,

the effect of corrosion is more pronounced at the high operating temperature under loaded condition.

The corrosion results will be validated by comparing to data from literature to ascertain the viability

of the proposed testing approach.

REFERENCES

Basu, P. (2010). Biomass Gasification and Pyrolysis. Oxford: Elsevier.

Hooshyar, H. (2016). High Temperature Corrosion of Stainless Steels in Low Oxygen Activity

Environments. Göteborg, Sweden: Chalmers University of Technology.



Understanding the Influence of Paint Baking on the HE Susceptibility of some

MS-AHSS.

Fang Yan LIM

Supervisor: Prof Andrej Atrens

Martensitic Advanced High Strength Steels (MS-AHSS) are predominantly used in the manufacture

of lightweight, crashworthy automobiles. A key issue in using these materials is its susceptibility to

hydrogen embrittlement (HE). Paint baking, a common thermal treatment applied to automotive

steels, can possibly change the hydrogen sensitivity of MS-AHSS. No prior research has been done

to study the influence of paint baking on the HE susceptibility of MS-AHSS. Such information may

be useful to the automotive industry as it could help define the applicability of these steels in car

manufacturing applications.

Four commercially available MS-AHSS (MS980, MS1300, MS1500, and MS1700) were studied.

These specimens were subjected to an annealing treatment at 180C for 30 minutes to simulate the

typical paint baking process. The steels were tested using the Linearly Increasing Stress Test (LIST)

to determine its threshold strength, the tensile strength, and the ductility. The specimens were tested

in different hydrogen environment representing different levels of hydrogen fugacity. In particular,

the test environments include tests in (i) air, (ii) 3.5 wt% NaCl at Ecorr, (iii) 3.5 wt% NaCl at EZn, (iv)

0.1M HCl at Ecorr, and (v) 0.1 NaOH at -1100 mVHg/HgO. The ductility of specimen was measured

using the scanning electron microscopy (SEM) testing. The fracture area and type of fracture was

also determined. The effect of hydrogen on the MS-AHSS was quantified by the hydrogen

embrittlement index, I.

Initial results indicate that annealing had no significant effect on the HE susceptibility of the lower

tensile strength specimens, i.e. MS1500, MS1300, and MS980. MS1700 was the most sensitive to

hydrogen among the tested steels. MS1700 exhibited an unexpected response to annealing. While it

was expected that the thermal treatment would reduce the hydrogen sensitivity of MS-AHSS, the HE

susceptibility of MS1700 actually increased after annealing. This was observed in the test

environments were more severe hydrogen conditions were present; i.e. (i) 3.5 wt% NaCl at EZn, (ii)

0.1M HCl at Ecorr, and (iii) 0.1 NaOH at -1100 mVHg/HgO.



(G65) Performance Benchmarking for NiHard Ore Chute Liner Alloys

Tim ZhuoXun CHEN


The main goal of this research project is providing a systematic performance benchmarking for

NiHard ore chute liner alloys due to its abrasion capability. Types of tests are suitable for such

purposes including RWAT (rubber wheel abrasion test), BMAT (ball mill abrasion test), and

BMECT (ball mill edge chipping test) and IC-SBAT (inner-circumference sliding-bed abrasion test).

Also, high-Cr-Mo white cast iron containing 15-27% Cr and 0-2% Mo are tested using the same

conditions to confirm whether NiHard has greater abrasion resistance as well as its own performance

due to its parameters, CVF (carbide volume fraction), Cr/C (Chromium/Carbide) ratio and chemical

composition.

As there are three students are involved in this research project, project allocations are produced by

Dr. Jeff Gates for the students to work individually and collaboratively. RWAT and BMAT are the

major test need to be performed. RWAT employs dry sand and rubber wheel to wear the surface of

the NiHard and high-Cr-Mo white cast iron to determine the weight loss during the same period of

time. There are 3 types of NiHard and 2 high-Cr-Mo white cast iron were tested. The types for the

NiHard are Y161, Y162 and Y163 while the high-Cr-Mo white cast iron are Y164 and CB100. They

are distinguished by their chemical composition. During the seminar, the following will be included:

researches and literature reviews, methodology of testing, RWAT results, BMAT results, hardness

measurements, microstructural inspections, the factors effects the results and future recommendation

of such projects. As high-Cr_Mo whit cast iron is the reference alloy to compare with the NiHard

alloy, the performance of NiHard under tests can be systematically generate a benchmarking. As this

project is willing to produce a performance benchmarking, hence the accuracy of the results are

essential and the same correct procedures must be followed for each test. How to improve the

accuracy of the test will be discussed in the seminar. The results from the RWAT shows that the

high-Cr-Mo white cast iron has higher abrasion resistance. Also, the wear rate decrease as hardness

increase, wear rate decrease as CVF increase and wear rate decrease as Cr/C increase. For BMAT,

the specific factors and parameters to obtain the desired data are designed and will be discussed

during the seminar. Currently, the BMAT has not yet completed and further data analysis need to be

manipulated to confirm whether the performance of the specimens are consisted with RWAT data

analysis.

In conclusion, IC-SBAT and BMECT are performed by other students within the projects, the data

will be shared and analysed to determine if the abrasion resistance changed due to the different type

of wear and testing conditions.



(G65) Performance Benchmarking for Ni-Hard Ore Chute Liner Alloys — ICAT

and RWAT

Will MARNANE

Supervisor: Dr J.D. Gates

Machinery and equipment used in the mining industry experience excessive wear during operation.

To minimise cost and maintenance downtime, consumable alloy liners or wear plates are used in

areas susceptible to wear. Ore chute liners are commonly manufactured using Ni-Hard 4, a white

cast iron containing approximately 9% Cr, 6% Ni, 3.2% C and 1.8% Si. Major competitors for this

application are ceramics and high Cr-Mo white cast irons containing 15-27% Cr and 0-2% Mo.

Currently, there is limited literature and data available on the performance characteristics between

the two alloys for this application. However, some papers (Dodd and Parks 1980) claim high Cr-Mo

irons are superior in terms of wear resistance, and especially fracture toughness.

Do high Cr-Mo white cast irons actually provide better abrasive wear resistance than Ni-

Hard 4, or is this common belief a result of industry bias influenced by the companies that

profit from high Cr-Mo alloy production?

The method of data acquisition to compare wear resistance is often from idealised laboratory tests

such as the rubber wheel abrasion test (RWAT). These wear tests are not industrially realistic, and

fail to resemble the wear conditions subject to ore chute liners. This project specifically looks at low

stress sliding abrasion (LSSA) with the intention of resembling the conditions in ore chutes. In

addition to the RWAT, a more industrially realistic test called the ‘inner circumference abrasion test’

(ICAT) was used to compare wear performance.

The ICAT results (Gates 2018) show strong correlations between wear rate and alloy parameters;

specifically, carbide volume fraction (CVF), chromium-carbon ratio (Cr/C) and hardness. There are

clear trends which suggest the wear rate decreases as CVF increases, Cr/C increases or hardness

increases.

For the alloys tested in this project, the high Cr-Mo irons have a higher CVF, Cr/C and hardness. To

more accurately analyse the effects between material parameters and abrasion performance spectral

analysis will be completed. This will give precise data for the chemical composition of each alloy,

reducing uncertainties.

Further testing is planned with the ICAT to include two additional high Cr-Mo alloys which will

bring the total to 10 metals; 5 Ni-Hard, 4 high Cr-Mo and Bis500, used as a reference material.

Based on the materials tested to date, it is likely high Cr-Mo alloys offer superior performance

compared to Ni-Hard 4 under low stress sliding abrasion conditions.

REFERENCES

Dodd, J. and J. L. Parks 1980, Factors affecting the production and performance of thick section

high chromium-molybdenum alloy iron castings. United States, Climax Molybdenum Company,

Greenwich, CT.

Gates, J.D 2018, Development of a Versatile Ultra-wear-resistant Brazed-block Product for Mining

and Ore Handling Operations – 2nd Annual Report, Report for Companhia Brasileira de Metalurgia

e Mineração (CBMM), Centre for Advanced Materials Processing and Manufacturing (AMPAM)



Model Based Predicative Control of a Solar Thermal-Diesel Hybrid System

Nisala C. HERATH

Supervisor: Dr M. KEARNEY

Australia, much like the rest of the world, is approaching an energy crisis and this adversely effects

those living in isolated rural towns. There are multiple factors that affect rising energy prices

however some of the dominate reasons are the rise in costs of gas and coal (Parkinson, 2013) and the

rise in cost of transmission as the energy networks expands (Barbour, 2017). The solution hence

involves cleaner, reliable and localised energy generation.

Concentrated solar power (CSP) is a process of focusing sunlight to generate heat energy that can be

used to power a thermal cycle. CSP with thermal energy storage (TES) can supply baseload power

and although thermal storage is significantly more affordable than batteries (Lazard, 2016). However,

as these systems are independent and have no support from the grid, reliability is imperative. TES

systems are generally very reliable however when considering the cost of a possible energy outage

for a whole town, it is ideal to have a back-up system. Deiseal generators are already a common in

rural Australia and it is possible to implement this technology to develop a hybrid solar thermal-

diesel system. A specific focus will be placed on modelling the hybrid system and developing a

controller to maintain baseload power.

The process of controlling the plant begins first with modelling. Due to the complexities of the solar

thermal plant, a non-linear model has been identified as necessary to develop an appropriate model.

The equations of the system have been adopted from Putten (2007) which describe a set of

differential equations for the feedwater pumps, heat exchangers and turbines. The cold and thermal

tanks will be modeled from first principles as a mixing problem with seperable differential equations

and the solar collector data is a discrete data set of solar irrdeance values from Solar.UQ (The

University of Queensland, 2017).

The model predictive control will be conducted by identifying by minimising the error function. The

error function is the set point signal minus or the power demand minus the output or the power

supply. The input is the power output by for the diesel generator and modelling the generator is a

work in progress. The controller is currently in development on MATLAB.

REFERENCES

Barbour, L. (2017). Rural businesses switch to diesel power as electricity prices soar. Retrieved

from ABC News: http://www.abc.net.au/news/2017-03-09/rural-businesses-turn-to-diesel-power-as-

electricity-prices-soar/8339346

H. van Putten, P. C. (2007). Dynamic modeling of steam power cycle: Part II - Simulation of a small

simple Rankine cycle system. Applied Thermal Engineering, 2566-2582.

Lazard. (2016). Lazard's Levelized Cost of Energy - Version 10.0.

Parkinson, G. (2013). Renewables now cheaper than coal and gas in Australia. Retrieved from

Reneweconomy: http://reneweconomy.com.au/renewables-now-cheaper-than-coal-and-gas-in-

australia-62268/

The University of Queensland. (2017, April 18). Retrieved from UQ Solar Photovoltaic Data:

http://solar.uq.edu.au/user/reportPower.php

http://reneweconomy.com.au/renewables-now-cheaper-than-coal-and-gas-in-australia-62268/

http://reneweconomy.com.au/renewables-now-cheaper-than-coal-and-gas-in-australia-62268/



Cd-Doped Tin Selenide Thermoelectric Materials

Angyin WU

Supervisors: Prof Jin Zou, A/Prof Zhi-Gang Chen

Energy crisis becomes increasing severe due to the large consumption of fossil fuels. Also, some

gases released by burning fossil fuels, e. g., CO2, NO, and NO2, lead to environmental issues. In this

case, clean and renewable energy resources are needed to substitute non-renewable fossil fuels.

Thermoelectric (TE) materials provide an available method for solving energy problems by

converting heat into electricity. The efficiency of the energy conversion is evaluated by figure of

merit, ZT, which is defined as:

TS

ZT

2

Where S, σ, T, and κ are Seebeck coefficient, electrical conductivity, absolute temperature, and

thermal conductivity, respectively. Thermoelectric performance increases with the ZT value. First

reported in 2014, the ZT value of single-crystal tin selenide (SnSe) reaches ~2.6 along b-axis (Zhao

et al. 2014). However, it is hard to put single crystal SnSe into use because of its poor mechanical

properties and rigid synthesis conditions. As a result, polycrystalline SnSe is put forward.

Compared to single crystal SnSe, polycrystalline has much lower ZT value due to its low electrical

conductivity and high thermal conductivity (Zhi-Gang Chen et al. 2016). To optimize the

thermoelectric performance of polycrystalline SnSe, doping is an available method. In this study,

cadmium (Cd) is chose as dopant because of its similar crystal structure with Sn. Four groups of

SnSe samples with different Cd concentrations, as well as pure SnSe sample, are synthesized using a

facile solvothermal method. After that, Sn1-xCdxSe (x=0, 0.05, 0.1, 0.15, and 0.2) powders are

sintered into bulks by spark plasma sintering (SPS). Then electrical property is tested using ZEM-3,

and thermal property is tested using LFA 457 (laser flash) and DSC 404 (differential scanning

calorimetry). To characterize the samples, XRD, SEM, and TEM are used.

From the XRD patterns, it is found that Cd is successfully doped into SnSe crystals. Second phase

CdSe also exists. Defects caused by Cd dopant and CdSe second phase can be observed significantly

on the SEM images. TEM image shows typical SnSe plate. In terms of TE performance, the

maximum ZT value reaches ~1.23 at 823K in Sn0.9Cd0.1Se sample. Compared with pure SnSe sample,

electric performance changes slightly due to the same valence of Cd2+ and Sn2+ ions. However,

thermal property changes significantly after doping. Defects induced by Cd dopants enhance the

phonon scattering and as a result reduce κ. However, with Cd concentration increasing, dopants

become excessive and form CdSe second phase, which deteriorates TE performance.

In conclusion, Cd-doping improves TE performance of SnSe by inducing defects on the crystals.

While excessive dopants lead to CdSe second phase, reducing TE property. A maximum ZT value of

~1.23 is achieved at 823K when the Cd dopant concentration is 10%.

REFERENCES

Li-Dong Zhao, et al., Ultralow thermal conductivity and high thermoelectric figure of merit in SnSe

crystals, Nature, 2014. 508: 373-377.

Zhi-Gang Chen, Xiaolei Shi, and Jin Zou, 2016, High-performance SnSe thermoelectric materials:

progress and future challenge.



Stress Corrosion Cracking of Pure Mg and Mg Alloys WE43 and EV31 in 0.1mol/kg 𝑵𝒂𝟐𝑺𝑶𝟒 Saturated with 𝑴𝒈(𝑶𝑯)𝟐

Yifeng LI

Supervisor: Prof A. Atrens

Due to the widespread use of pure magnesium and its alloys in modern industry, the study of their

performance has become particularly important. This thesis mainly studied the SCC performance of

pure magnesium and its alloys WE43 and EV31 in solution (0.1mol/kg 𝐍𝐚𝟐𝐒𝐎𝟒 saturated with

𝐌𝐠(𝐎𝐇)𝟐). The major test method to apply linear increasing stress to the specimens was LIST,

which was introduced by Atrens et al. (1993). Increasing applied stress to specimens would reduce

their cross-sectional area and increase their length, which leads to the increase of electrical

resistance. So that potential drop of the specimen was collected as experimental data to reflect the

response of specimens to the applied stress. After LISTs, the micrograph and SEM were taken to

analyze the characteristic of their fracture surfaces and cracks.

The aim of doing SCC tests was to compare the SCC performance with normal performance (in air).

In this experiment, LISTs were proceeded in two different environments with two different stress

rates. There were 18 groups of data recorded in total. In each data graph, the potential drop data

could always be assumed as a line chart with only one inflection point. The line started from a slight

slope line and kept for a period of time, then it suddenly raised with an abrupt slope until stop.

Mechanical properties include yield stress, threshold stress and ultimate tensile stress were obtained

by measuring the position of inflection point and fracture point in the potential drop data graph, and

then the SCC susceptibility could be calculated. The formula of calculating the SCC susceptibility is

given by Shi et al. (2015).

Several conclusions have been drawn after analyze the experimental data and photos,

1. These two Mg alloys have much better mechanical properties than Pure Mg, and they also

showed better corrosion resistance in this experiment.

2. The solution (0.1mol/kg 𝐍𝐚𝟐𝐒𝐎𝟒 saturated with 𝐌𝐠(𝐎𝐇)𝟐) decreased the performance of Pure

Mg, WE43 and EV31 in different degree.

3. After calculation, the SCC sensitivity of Pure Mg is much larger than WE43 and EV31, and

EV31 have the lowest SCC sensitivity (𝑰𝒔𝒄𝒄: Pure Mg >> WE43 > EV31).

4. The SCC sensitivity of Pure Magnesium and its alloys would increase when decrease the applied

stress rate, and the sensitivity is dynamic at different applied stress rate.

5. All the specimens showed surface cracks in side view micrographs, and the specimens suffered

more corrosion when decrease the stress rate.

6. The stress corrosion cracks started form at the surface of the specimen, and they always initiated

and grown independently. The surface crack appearances of the three kinds of materials are

similar in different condition, and the lateral cracks are parallel along the fracture direction.

REFERENCES

A Atrens, 1993. Linearly increasing stress test (LIST) for SCC research. Measurement Science and

Technology, 4(11), pp.1281–1292.

Shi et al., 2015. Stress corrosion cracking of high-strength AZ31 processed by high-ratio differential

speed rolling. Journal of Magnesium and Alloys, 3(4), pp.271–282.



High Temperature Polymer Matrix Materials for Next Generation Fibre

Reinforced Plastics

Antoine POULIQUEN


Nowadays, many challenging industries such as military or aerospace are trying to develop new

products with higher performance at a lower cost. One of the main area of research is materials.

Metal was the most commonly used material thanks to its mechanical properties. Industries tend to

change towards polymer matrix composites materials which can show same mechanical

characteristics while being lighter and cheaper.

Polymer matrix composites are now commonly used, however their use at high temperature is still in

development. This is why I have done a literature review of all the different resin types that can be

used at temperatures higher than 200°C, such as polyimides, cyanate esters, BMIs, benzoxazines,

phthalonitriles, phenolic resins and lately MG resins.

After the study of all those resins, it has been chosen to test two of them, BMIs and cyanate esters.

BMI resins are widely used in the aerospace industry and present cheap price, relatively easy

processability and good hot/wet performances. Cyanate ester resins present quite similar

characteristics when compared to BMIs and are considered the future of high performance resins

therefore it was decided to purchase tests on this resin type.

However, it is sometimes difficult to obtain those resins, this is why we decided to test mechanically

two other resins that are SMP10 and SPR68 in order to be able to compare characteristics of many

different resins.

After this study, plates were processed and later cut so we can obtain the specimens and do the

mechanical tests to obtain the different characteristics to ease the choice of resins in the future.

Tension, compression and 3-point bending tests were chosen to determine the mechanical

characteristics of the resins. Those tests will be coupled to an evaluation of the density, fracture

volume fraction and porosity of the composite specimens processed.

REFERENCES

Department Of Defense Washington DC, 2002. Composite Materials Handbook. Volume 1. Polymer

Matrix Composites Guidelines for Characterization of Structural Materials, Society of Automotive

Engineers, Inc.

McConnell, V. P. 2009, Resins for the Hot Zone, Part I: Polyimides, CompositesWorld.com, viewed

18 April 2018, <https://www.compositesworld.com/articles/resins-for-the-hot-zone-part-i-

polyimides>.

McConnell, V. P. 2009, Resins for the Hot Zone, Part II: Polyimides, CompositesWorld.com, viewed

18 April 2018, <https://www.compositesworld.com/articles/resins-for-the-hot-zone-part-ii-bmis-ces-

benzoxazines-and-phthalonitriles>.

https://www.compositesworld.com/articles/resins-for-the-hot-zone-part-i-polyimides

https://www.compositesworld.com/articles/resins-for-the-hot-zone-part-i-polyimides



Exhaust Gas Heat Recovery in Diesel Engine Using Organic Rankine Cycle

Tushar B. KARAD

Supervisor: Prof Hal Gurgenci

Waste heat from an engine is the heat which is released into the environment from the exhaust of an engine

without being further used. In case of an Internal Combustion heat, out of the total generated in the

cylinder mainly 45% of the heat gets converted into mechanical work and the cooling purposes of

the engine and the rest is released into the environment directly (Hatami, Ganji, & Gorji-Bandpy,

2014). The exhaust gas heat temperature for an IC Engine ranges from 300oC-550oC, therefore it is of

utmost importance to utilize this heat for the internal purpose of the car. Several methods can be

considered for recovering waste heat from an engine, but the use of organic rankine cycle is most efficient

(Hatami et al., 2014).

Waste heat recovery system mainly consists of the heat exchanger, used for extraction of heat from the

exhaust and Organic rankine cycle, where the exhaust gas heat recovered is utilized to heat the organic

fluid of the cycle, after which energy is generated from the turbine of the cycle (Vaja & Gambarotta,

2010). The configuration of organic rankine cycle can be intricate and selection of organic fluid in the

cycle can affect the efficiency of the heat recovery system due to variation in the physical and chemical

properties of the fluids (Vaja & Gambarotta, 2010). The other important factor to be considered while

using the waste heat recovery system is the effect of the backpressure occurring on IC engine when the

heat is extracted from the exhaust. During heat extraction at the exhaust by the heat exchanger,

backpressure is generated which finally affects the overall efficiency of the engine (Cong, Garner, &

McTaggart-Cowan, 2011). If the backpressure exceeds, and creates performance degradation for the IC

engine, then the purpose of heat recovery is not fulfilled. Therefore, the design of the rankine cycle and

study of the backpressure effect are the two important factors in the study of waste heat recovery in diesel

engine.

Research study and data analysis of a range of experiments concluded that organic rankine cycle can be

more efficient if there is more than one heat exchanger is considered for extraction of heat (Vaja &

Gambarotta, 2010). However, considering a vehicle addition of extra heat exchanger adds on to the total

weight of the vehicle and makes the system more complex, making standard organic rankine cycle as the

best suited for the process (Vaja & Gambarotta, 2010). R245fa which is Penta floro propane, was selected

the organic fluid after considering the properties such as latent heat of vaporization, specific volume and

dry and non-toxic nature of the fluid (Vaja & Gambarotta, 2010). Backpressure effect is studied by a

mathematical model of the heat exchanger, the ideal configuration of the heat exchanger is used for the

calculation purpose. The backpressure effect for the same configuration but different exhaust temperature

is calculated. The study presented that heat extraction has a significant backpressure effect on the system

(Cong et al., 2011) and further study is required to mark the permissible backpressure to achieve maximum

performance of diesel engine.

REFERENCES

Cong, S., Garner, C. P., & McTaggart-Cowan, G. P. (2011). The Effects of Exhaust Back Pressure on

Conventional and Low-Temperature Diesel Combustion. Proceedings of the Institution of Mechanical

Engineers, Part D: Journal of Automobile Engineering, 225(2), 222-235.

doi:10.1177/09544070JAUTO1577

Hatami, M., Ganji, D. D., & Gorji-Bandpy, M. (2014). A review of different heat exchangers designs for

increasing the diesel exhaust waste heat recovery. Renewable and Sustainable Energy Reviews, 37, 168-

181. doi:10.1016/j.rser.2014.05.004

Vaja, I., & Gambarotta, A. (2010). Internal Combustion Engine (ICE) bottoming with Organic Rankine

Cycles (ORCs). Energy, 35(2), 1084-1093. doi:10.1016/j.energy.2009.06.001



Affordable Tooling/Manufacturing for Small Scale Production

Marlunn Eric ODUCAYEN


Permanent mold casting is a metal casting process that employs reusable molds (also known as

permanent molds) usually made from tool steel or cast iron. It is often an economical option for

producing 10,000 to 100,000 parts, however, a major limitation is the high tooling costs which

makes this process uneconomical for small to mid-volume production of parts, e.g. in the range of

1000 to 10,000 parts, which are normally the number required for military vehicle production. The

high tooling costs are attributed to the intense labor attached to casting the mold block and long

machine hours to make the mold cavities. Additive manufacturing such as 3D printing technology

offers a great alternative to the traditional tooling methods as it may offer a faster, more affordable

and less labor-intensive tool manufacturing process.

The project’s aim is performing a benchmark study on the viability in which molds are made. This

benchmark study looks to compare an alternative technique from the additive manufacturing field

(using a 3D sand printer) to manufacture molds, against conventional mold manufacturing

techniques to see which will have better costs for mid-volume production runs. Thus, factors such as

machining time, tooling and labor costs are important parameters that will be used for comparing all

mold manufacturing processes. The mold manufacturing techniques that are being investigated for

the project are machining down blocks of H13 tool steel and sand casts (conventional techniques)

versus using 3D printed sand molds that achieve a near net shape cast for the die blocks. To note, the

same molds (supplied) are used for each manufacturing technique.

The methodology used to conduct the project are as follows:

1) To use CAD/CAM software to program tooling paths to obtain expected machining times for

the mold dies from machining H13 and sand cast blocks

2) Create a cost spreadsheet that uses the expected machining time to find the cost of making a

mold. This spreadsheet is also used to compare how much it will cost for part production

runs of up to 10,000 parts

3) Investigate and evaluate the 3D Sand Printer’s costs by obtaining machining time, hire rate,

tooling and associated labor costs to manufacture the supplied die blocks and compare them

to the conventional techniques of machining down from tool steel and cast-iron blocks

Currently, tooling paths have been programmed based of the required tooling parameters needed to

machine H13 and sand cast blocks and expected machining times have been obtained.

The next phase for the project is to evaluate the 3D Sand Printer’s costs associated with

manufacturing the supplied molds and compare costs between manufacturing with it versus

machining H13 and sand cast blocks in order to recommend the most viable option for

manufacturing at a mid-volume scale.



Characterisation of Surface Tension of Zn-Al based Alloys

Day W. TAN

Supervisor: Prof K. Nogita and Dr S. McDonald

Steel is a common metal alloy very widely used in various industries all over the world. However, it

is prone to corrosion when exposed to natural atmosphere and the main method of protecting steel

against corrosion is coating or galvanizing with zinc. Due to several criteria not met by a purely zinc

coating, a Zn/55Al alloy coating known as Galvalume® has been developed and applied using hot

dip continuous process (Moreira et al., 2006). This thesis is part of a larger research project

investigating several properties of similar Zn-Al alloys to optimise commercial manufacturing

processes. The main scope of my research will be to investigate surface tension properties of three

proprietary Zn-Al alloys - AZ, AM1 and AM2 -provided by BlueScope Steel.

When a small volume of a liquid collects on a horizontal plane surface of a material that it does not

wet, an almost-spherical shape is formed and large drops in this condition are known as sessile drops

(Sprackling, 1985). Initial experiments were conducted in a non-oxidising nitrogen atmosphere with

quartz glass in place of steel as substrate. The surface tension of said liquid or in this case, molten

metal, can then be deduced from a photograph of its sessile drop profile using Dorsey’s Method

which is well suited for the experimental setup used (Dorsey, 1928). Using a SEM (scanning electron

microscope), the microstructure of each alloy sample and its sessile drop’s cross-sectional profile

was also examined.

Experimental results revealed that the average surface tension of AZ samples is much higher than

both AM1 and AM2 (up to 52% higher) while AM1 and AM2 samples has a negligible difference of

only 1.5%. The absolute values of AZ, AM1 and AM2’s surface tension has high standard deviations

of 45%, 31% and 40% of their mean respectively, implying that there might be uncertainties that

need to be investigated. Nevertheless, the trend of these results matches projected expectations.

REFERENCES

Dorsey, N. E. 1928. A new equation for the determination of surface tension from the form of a

sessile drop or bubble. Journal of The Washington Academy of Sciences, 18, 505-509.

Moreira, A. R., Panossian, Z., Camargo, P. L., Moreira, M. F., Silva, I. C. D. & De Carvalho, J. E. R.

2006. Zn/55Al coating microstructure and corrosion mechanism. Corrosion Science, 48, 564-576.

Sprackling, M. T. 1985. Surface effects. Liquids and Solids. Dordrecht: Springer Netherlands.



Mapping the Battery System around the World

Pengfei LIU


Energy is a central topic in engineering, every design need to take energy consumption into

consideration to lower the cost or make the whole procedure more efficient. With the increased

uptake of renewable, energy storage is a paramount system. This project is to find the distributed

situation about one of the most useful energy storage system in the world, the battery energy storage

system to provide the more efficient method of founding the battery energy storage system.

The first thing is to gain the information of all the known installation around the world and classify

them by the type of battery that been used in the energy storage system. Due to the information

shown in the DOE [1], the major types of the battery are: Lithium ion battery, lead acid battery,

metal air battery, flow battery and nickel based battery. Also, the size of the installation should also

be taken into consideration so that while drawing the map, the colour of the marks will be used to

present the types of the used battery and the shape will be used to classify the size of the installation

whether is between 1 to 10 MW or larger than 10 MW.

After summarizing these information, the most important thing is to compare the usage of these

installations. As the result shown that most of these installations are used in the national grid to

storage the energy or being used to modify the change during power delivery, for example, the most

frequent usage of these installations is frequency regulation.

At last, the comparison should be made between the battery energy system and traditional energy

storage system, such as the pump hydro energy storage system. This comparison should be made to

illustrate why the engineers want to use the battery energy storage system. For example, the response

time of the battery energy storage system is extremely short and will supply the energy in a short

time.

However, the requirement of building the battery energy storage system is very stringent for the

consistency of the battery system except for the flow battery. As is known that, most of the battery

storage system is consist of series of single cell. While charging, if there is only one cell, for example,

the capacity of this cell is just 90% of the other cell, the whole system will be charged only 90%

energy which is much lower than the engineer’s plan.

REFERENCE

1. Energystorageexchange.org. (2017). DOE Global Energy Storage Database. [online] Available

at: http://www.energystorageexchange.org/projects [Accessed 25 Oct. 2017].

2. Power Magazine. (2017). Revived Energy Storage Technology Offers Major Grid Benefits.

[online] Available at: http://www.powermag.com/revived-energy-storage-technology-offers-

major-grid-benefits/ [Accessed 20 Oct. 2017].



Application of Solar Power on Air Conditioning in Closed Greenhouse

Huang HUI

Supervisor: Prof Hal Gurgenci

As the industrial level and global food and energy shortage had been both increased greatly in last

decades, human race are facing an increasingly challenging energy and food situation. With the help

of greenhouse, more crops like fruits and vegetables can be produced with better quality. In order to

adjust the inside air condition to appropriate scope for crops, in this case, solar based air conditioning

system is selected to control the humidity and temperature inside the closed green house. There are

two mainstream traditional air conditioning methods of closed greenhouse, which is ground heat

water heat pump (GHWP) system and vapor compression heat pump (VCHP) system.

Nowadays, 94% of the energy people use on earth were from the radiation power of sun (Krauter S.

2006). And in this closed greenhouse project, the renewable Energy, solar power is applied to the

indoor air conditioning system. Two ways of energy utilization can be selected, which is direct

method (heat based) and indirect method (electricity based). According to previous studies, the

energy conversion efficiency of direct method can be much higher than electricity based system, as a

result, heat based air conditioning system is the main discussion object in this closed greenhouse case.

The category of heat based air conditioning system is divided into 3 types, which is absorption

system, adsorption system and desiccant system. Each of them has its own advantages and

drawbacks, after the comparison between these three different heat based system from different

aspects like economical analysis, operation costs and service life, absorption air conditioning system

is selected to control the indoor air. The basic working principle of absorption system is that when

substance is absorbed or released to another one, resulting in a change in the state of the

substance ,and this process is accompanied by an endothermic and exothermic procedure. The most

common working pairs for absorption systems are lithium bromide-water (H20/LiBr) solution and

ammonia-water (NH3/H2O) solution, in this case the latter pair is selected because of its higher COP

value in room temperature cooling environment(Zhang. X et al 2015).

In order to build up the whole system, real time heat load and COP simulation is necessary to this

project. As for system parts building, solar collectors, heat exchangers are also designed in this

project. The result of system simulation shows that absorption system can be better than traditional

system both in perspectives of economy and performance.

REFERENCES

Krauter, S. 2006, Solar Electric Power Generation, Springer, Berlin, Heidelberg, New York.

Zhang, X., Li, H., & Yang, C. 2015. A Novel solar Absorption Refrigeration System Using the

Multi-Stage Heat Storage Method. Energy and Buildings, 102, 157-162



Oxidation Stimulation Technique to Enhance Coal Permeability: Mechanism of

NaClO Reaction with Different Coal Macerals Composition

Ziqiang LIU

Supervisor: Dr Karen Steel, Zhenhua Jing

Coal Permeability is one of a key controlling factor in coal seam gas (CSG) extraction from coal

seam. Therefore effective coal permeability enhancement is crucial to be established. The concept of

using oxidation to enhance coal permeability has been discussed in these recent year. (Jing et al.,

2018) Oxidation like sodium hypochlorite has been studied in coal structure investigation in many

years and showed significant effects on coal.(Mayo, 1975, Yao et al., 2010) However, the

mechanism of coal oxidation has yet to emerge. In this project, the author conducted a series of

experiments to investigate the mechanism of coal oxidation in a specific aspect: effect of different

coal macerals composition (vitrinite and inertinite). Because different coal maceral type has a huge

difference in chemical structure, (Van Niekerk et al., 2008) coals with different maceral composition

would definitely behave in different performance. Camera-observation ‘swelling test’ and

complementary leaching test was conducted to determine the maceral oxidation performance. Also,

different types of in-situ spectroscopy technique was used to analyse components of oxidation

product.

Results provide evidence for coal swelling in both vitrinite (maximum particle size increase= 8%)

and inertinite (maximum particle size increase= 10%). Also, based on the oxidation phenomenon, the

author proposed that coal oxidation might be a ‘positive feedback’ reaction (in both vitrinite and

inertinite), which means the reaction rate would keep increasing as the oxidation goes on. Products

from formal oxidation would be more reactive. From the result data of leaching test, mass loss after

the oxidation in vitrinite is similar to that of inertinite. And more experiments are still in process.

REFERENCES

Jing, Z., Balucan, R. D., Underschultz, J. R. & Steel, K. M. 2018. Oxidant Stimulation For

Enhancing Coal Seam Permeability: Swelling And Solubilisation Behaviour Of Unconfined Coal

Particles In Oxidants. Fuel, 221, 320-328.

Mayo, F. R. 1975. Application Of Sodium Hypochlorite Oxidations To The Structure Of Coal. Fuel,

54, 273-275.

Van Niekerk, D., Pugmire, R. J., Solum, M. S., Painter, P. C. & Mathews, J. P. 2008. Structural

Characterization Of Vitrinite-Rich And Inertinite-Rich Permian-Aged South African Bituminous

Coals. International Journal Of Coal Geology, 76, 290-300.

Yao, Z.-S., Wei, X.-Y., Lv, J., Liu, F.-J., Huang, Y.-G., Xu, J.-J., Chen, F.-J., Huang, Y., Li, Y., Lu,

Y. & Zong, Z.-M. 2010. Oxidation Of Shenfu Coal With Ruo4 And Naocl. Energy & Fuels, 24,

1801-1808.



Electrolyte for Lithium-Sulfur Battery

Yishu CHANG


Lithium-sulfur battery is one of the best potential Li-ion battery for its theoretical specific energy.

The specific energy can be reached around 2600 Wh/kg which is five times higher than traditional

Li-ion batteries. This battery can be used wildly in manufacturing, transport and energy industry. Not

only act as a energy supplier, lithium-sulfur battery

The gap between theoretical energy and practical energy is “Shuttle” effect. This effect is due to the

intermediates of chemical reactions. Some intermediates are soluble in the organic liquid electrolyte

and these soluble chemicals can freely move around the whole battery (Zhang 2013). Reactions

happed on cathode is preferred but due to de movement of intermediates, reactions happened in the

anode as well. This unexpected reaction causes the loss of energy and will affect the anode quality

for the cycling of battery.

To address this problem for lithium-sulfur battery, solid electrolyte applied. Wildly used material for

solid electrolyte is PEO. PEO is a linear polymer with a helical structure. It has high percentage of

crystallization and low transform temperature. For the conduction action press, PEO has

crystallization area conduction action process and un-crystallization area conduction action press.

When we heat up the material, crystallized area will absorb energy and break coordination bond. Ions

can move freely then the vacancies appear. Those vacancies are the pathway for Li-ions to move

from anode to cathode. At the same time, un-crystallized area will messily move due to the rise of

temperature. Vacancies between different lines appear and provide more pathway for Li-ion to move.

Un-crystallized area has much more conductivity and the best result is to have as much un-

crystallized as possible for solid electrolyte (Nazar, Crusinier & Pang 2014).

Crosslink is using short chains to support long chains and re-build materials. Crosslink for PEO can

effectively reduce crystallization of PEO. In this project we use MBP and TGD to mix with PEO.

After hot press and UV light treatment. We have the solid electrolyte for lithium-sulfur battery.

REFERENCE:

1. Nazar, L. F., Cuisinier, M., & Pang, Q. (2014). Lithium-sulfur batteries. MRS Bulletin, 39(5),

436-442.

2. Zhang, S. S. (2013). Liquid electrolyte lithium/sulfur battery: fundamental chemistry, problems,

and solutions. Journal of Power Sources, 231, 153-162.



Understanding the Impact of Connected Environment on Human Factors Using

Car-Following Model

Rajath KRISHNAMURTHY

Supervisor: A/Prof Zuduo Zheng

Connected vehicles share critical surrounding information such as leading vehicle’s speed, spacing to

the leading vehicle, accident in the upstream traffic etc. However, to follow or to ignore this

information assistance is still in driver’s control. Undoubtedly, in connected environment, human

factors will play a major role in governing the driving tasks such as car-following (CF) (Sharma, Ali,

Saifuzzaman, Zheng, & Haque, 2017) for a discussion on human factors linked with connected

vehicles). Hence, this study aims to investigate the impact of Connected environment on human

factors and highlights the importance of incorporating these factors in CF models.

CF models have made a significant progress in past 50 years, still consideration of human factors in

CF models are largely ignored except a few notable attempts. TDIDM is a successful integration of

difficulty in driving task (a human factor) denoted by TD and Intelligent Driver Model (IDM)

(Treiber, Hennecke, & Helbing, 2000). (Saifuzzaman & Zheng, 2014) formulated TD using

renowned Task Capability Interface (TCI) model and includes, spacing between subject vehicle and

the leader, speed of the subject vehicle, desired time headway, a risk parameter, a modified reaction

time and a sensitivity parameter which is used to capture driver’s sensitivity towards the task

difficulty level. TDIDM model is considered in this study because it outperforms its predecessor

models especially in the presence of human factors.

To achieve the aforementioned aim, the TDIDM model is rigorously calibrated and validated using

the baseline and the connected environment trajectory data. The calibration results will assist in (a)

understating the TDIDM’s capability to describe the connected vehicle CF dynamics, and (b)

comparing the calibrated parameter sets obtained from the baseline and the connected environment

data to gain insights about the impact of connected environment on human factors. On the other

hand, the validation results will assist in judging the predictive capability of TDIDM.

REFERENCES

Saifuzzaman, M., & Zheng, Z. (2014). Incorporating human-factors in car-following models: A

review of recent developments and research needs. Transportation Research Part C: Emerging

Technologies, 48, 379-403. doi:https://doi.org/10.1016/j.trc.2014.09.008

Sharma, A., Ali, Y., Saifuzzaman, M., Zheng, Z., & Haque, M. M. (2017). Human Factors in

Modelling Mixed Traffic of Traditional, Connected, and Automated Vehicles. Paper presented at the

International Conference on Applied Human Factors and Ergonomics.

Treiber, M., Hennecke, A., & Helbing, D. (2000). Congested traffic states in empirical observations

and microscopic simulations. Physical Review E, 62(2), 1805-1824.

https://doi.org/10.1016/j.trc.2014.09.008



Finite Element Analysis of Imperfect Structural Sections under Compression

Andrew TANG

Supervisor: Dr C. Leonardi

The behaviour of structural sections under compressional forces have been analysed and investigated

throughout the years due to their sheer importance in present day construction. With their properties

and load capacities defining the overall structure’s capabilities. Ultimately, the structural section will

become unstable and collapse in the form of buckling, being the main failure limit-state for columns

and structures under axial compression (Segui 2012). Compressive failure can almost act instantly

whereas ductile forces and failure is well predicted.

For perfect members, the structural section can be predicted by the classical buckling theory to

formulate the critical load (Bjorhorde 1998). However, the same cannot be said for imperfect

structural section, with imperfections drastically affecting the properties and load capacities. With

manufacturing defects such as geometrical perturbations and residual stresses exhibiting effects on

load capacities and stress distribution. Thus, a sensitivity analysis regarding imperfections and load

capacities, will help enhance engineering design and mitigate failure within the future.

This investigation aims to provide a means to analyse the sensitivity of imperfect structural sections

under compressional forces with the implementation of finite element analysis (FEA) and analytical

methods. The analytical methods involve the usage of permitted tolerances and equations through

various structural steel standards for design. These tolerances and equations impose a relevantly safe

method for the assessment of structural sections. However, the methods of the Australian (AS4100-

1998), American (ANSI/AISC 360-16) and the European (Eurocode 3 1993-1-1) variants differ and

thus varying results. Nevertheless, all standards were noted to be conservative with the initial testing

of FEA. The FEA results displayed much greater failure loads than calculated, even lower calculative

values with further safety factors. It is worth noting, an even larger percentage difference with the

Euler’s buckling load, however this could be the difference in detail.

ABAQUS was the chosen FEA tool, the simulations incorporated both linear buckling, non-linear

buckling analysis and other primary methods of solvers. Although non-linear buckling analysis

exhibits a more realistic result, the linear buckling analysis produced necessary eigenvalues and

mode shapes to be further utilized for the imperfection analysis. Simulated models varied in

boundary conditions, materials and measurements however within the fabrication tolerances of

AS5131:2016 (Structural Steelwork – Erection and Fabrication) and other standards.

On a side note, the AS4100-1998 includes a summary on advanced structural analysis which

involves geometrical imperfections, residual stresses, second-order effects and more. However,

lacking the detail when compared to ANSI/AISC 360-16 and EN3 1993-1-1 for imperfect members.

A hybrid investigation in conjunction with failure limit load and stresses previously attained was

further tested for viability in the bounds of AS4100-1998. Considering it was a key factor to inspect

during the analytical research.

REFERENCES

Segui W., 2012 Steel Design. 5th ed. Stamford, CT, USA: Global Engineering: Christopher M.

Shortt

Bjorhovde R., 1998 ‘Columns: From Theory to Practice’ Engineering Journal, American Institute of

Steel Construction, Vol. 25, pp. 21-34.



Numerical Study of Aerodynamic Analysis of Typical Blades on Darrieus Type

VAWTs

Yueyang JIANG

Supervisor: A/Prof Kamel Hooman (Dr Yuanshen Lu)

As we all know, the wind turbines could be classified into two types in general, which is HAWT

(Horizontal axis wind turbines) and VAWT (Vertical axis wind turbines) (Mazharul Islam 2006).

However, the development of VAWT dates back to late 1970s and early 1980s, ‘notably at the USA

Department of Energy Sandia National Laboratories and in the UK by Reading University, and Sir

Robert McAlpine and Sons Ltd’ (Howell, 2010). But VAWT did not make significant progress since

it became accepted that the HAWT was a more efficient solution at these large scales. Through the

project an organised method of controlling the parameters is generated to study the performance of

the VAWTs in some typical blades. The airfoil data is generated from the NACA tested data

published in 1935. The data is used to build up the airfoil model and then applied into the simulation

process. The desired result would show us the contours of different variables of airfoil and the Lift

Coefficient and Drag Coefficient plot would be mainly focused to help us analyse the performance of

the VAWT airfoils. And different angles of attack result in different efficiencies. So after analysing

the initial 0 ° angle of attack, more different angles would be proceeded in similar process with

dividing 360 ° equally into 36 parts. If time permitting, after the 2D analysis, a more complex 3D

model would be studied, which means more monitors created and more complex boundary

conditions setting. The overall structure of method is also suitable for other types of airfoils. Finally,

the simulation results should be matched with existing published data in similar scenarios when

controlling variables. A quick check of the simulation results is recommended and necessary.

REFERENCES

Howell, R. et al., 2010. Wind tunnel and numerical study of a small vertical axis wind turbine.

Renewable energy, 35(2), pp.412–422.

Islam, M., Ting, D. & Fartaj, A., 2008. Aerodynamic models for Darrieus-type straight-bladed

vertical axis wind turbines. Renewable & sustainable energy reviews., 12(4), pp.1087–1109.



Piston Braking System for X3R

Kunfeng GAO

Supervisor: Prof R. Morgan & Dr D. Gildfind

As the engineering technology developing, the requirement of the high-speed vehicles or aircrafts

becoming more and more sophisticated and rigorous. The more efficient way is to test the small-

scale model first. When the speed requirement reaches the level of supersonic or hypersonic, the

traditional wind tunnel is out of requirement and the shock tube is carried out, which can create the

speed of the air flow up to 2 km/s, which is the sub-orbital speed. [1]

When operating the shock tube, the piston may go backward in the process, which is called ‘rebound

impact’ and it is the situation that must be avoided. In order to prevent possibility of the rebound

impact, installing a brake system on the piston is one of the most efficient and helpful methods.

The whole brake is comprised by four equal size brake shoes presenting as a circumferential ring

around the piston. The brake shoe’s cross section is wedge shaped. A brake shoe is combined by

levels of a brake pad, adhesive, a brake basement and a cover coat. During a deceleration process of

piston, the brake shoes will slide above the piston surface and start to offer a frictional force by the

friction force. The frictional force created by the brake will help the piston to stop and prevent it

from rebounding back.

The main requirement of the braking system on the piston is the frictional coefficient should be

sufficient to avoid the piston from rebounding. Otherwise, the braking system should not make any

damage to itself or other facilities.

For design work, the angle of the brake shoe inner surface and the length of the brake shoe are the

parameters that should be decided. For analysis, the most important parameters that matter are the

normal stress and the sheer stress between the brake shoes upper surface and the tube wall internal

surface. After collecting and analyzing the geometry of X3R and former X3R operating data, a brake

shoe whose angle is 9° and length is 170 mm, which is due to the limitation of the material of the

brake pad’s compressive strength and shear strength.

The materials of the different levels of a brake shoe is also part of design work. The brake pad’s

material is D3806. The brake basement’s material is Aluminum 6061-T6.

REFERENCES

[1] Stalker, Paull, Mee, Morgan, & Jacobs. (2005). Scramjets and shock tunnels—The Queensland

experience. Progress in Aerospace Sciences, 41(6), 471-513.



Biomedical Meets Robotics: Deep Brain Stimulation

Soraya BROSSET

Supervisor: Dr Peter Jacobs

Deep Brain Stimulation is a medical procedure which goal is to reduce tremors for patients with motion

disorder (Parkinson’s disease etc.). One or two electrodes are carefully inserted within the brain to stimulate

the faulty area. It has to be meticulously planned, as the electrode must avoid any interference with blood

vessel to preserve all cerebral functions. To plot the adequate path for the electrode, a new software SOFA

DBS, which stands for Stimulation Open Framework Architecture, Deep Brain Simulation, has been

recently implemented. It presents some novelties: it computes the Cerebro-Spinal Fluid loss and the air

subdural invasion of the brain during the surgery. It also represents its consequences on the brain shift and

the electrode migration: this can significantly help reducing medical complications after the DBS

procedure, such as intracranial haemorrhages.

CSF loss and subdural air invasion

SOFA uses the fundamental principle of dynamics applied to the brain (taking into account the force of the

CSF fcsf):

h: time step; M: masse of the brain; B: damping matrix; K: stiffness matrix; f : internal and external

forces applied on the system (due to the electrode insertion, f=fneedle); represents both the

constraint from the contact with the skull and the Dirichlet boundary conditions.

It has been proven experimentally that the electrode displacement D and subdural air volume V can be

linked by : D=2+0.08V, (Van den Munckhof et al., 2010).

Set of constraint on the human brain used on SOFA, (Bilger et al., 2014). Electrode migration after DBS Surgery, (Van den

Munckhof et al., 2010)

Needle insertion

The brain will be modelled using gelatine. The force of insertion of the electrode on the brain is

modelled by:

fstiff is experimentally determined by poking the surface. E1 is the Young modulus of the needle and E2 is

the Young modulus of the soft tissue (gelatine, determined experimentally here). D is the diameter of the

needle. υ2 is the Poisson modulus. h is the length of the needle that is already inside the tissue, (Jiang et al.,

2014).

In matter of ‘rigidity and tremor’, the improvement after DBS was between 70–75% which constitutes a

dramatic increase of the standards of living for patients (Benabid et al., 2009).

REFERENCES Bilger, A. (2014). Patient-specific biomechanical simulation for deep brain stimulation. Université des

Sciences et Technologie de Lille, Van den Munckhof, P., Contarino, M. F., Bour, L. J., Speelman, J. D., de

Bie, R. M., & Schuurman, P. R. (2010). Postoperative curving and upward displacement of deep brain

stimulation

Jiang, S., Li, P., Yu, Y., Liu, J., & Yang, Z. (2014). Experimental study of needle–tissue interaction forces:

effect of needle geometries, insertion methods and tissue characteristics. Journal of biomechanics, 47(13),

3344-3353.

Benabid, A. L., Chabardes, S., Mitrofanis, J., & Pollak, P. (2009). Deep brain stimulation of the

subthalamic nucleus for the treatment of Parkinson's disease. The Lancet Neurology, 8(1), 67-81.



Sweet Arm Robot

Sebastien P. SUTTER

Supervisor: Dr Surya P. N. Singh

This thesis is dealing with the prehension of objects with a delta robot. The project is splitted in four

parts which are the computational vision, the soft end effector and the conception of the delta robot

and the experimental design of the grasping testing.

The robot will be used to test the grasping of objects using different version of soft pneumatic

end effectors.

The first part of my thesis consists in the creation of a program which display the action of the robot

on the environment. This will allow to be aware of any dysfunctionalities before actually giving the

order to the robot. In order to do so, I based the program on the work of R. Sukthankar, R. Stockton

and M. Mullin (2001) on the auto-calibration of a projector and a camera.

The second part of the thesis focus on the soft end effector of the robot. More and more, the robots

will be part of our lives. It appears that soft actuators can increase the safety of the users while robots

interacting with humans and/or fragile objects. A simple way to create them is to use silicone or

elastomers and 3D printed casts (J. Hughes, U. Culha, F. Giardina, F. Guenther, A. Rosendo and F.

Iida, 2016). The simplicity of the process allows to cast many different version of the end effector,

changing the casts and the materials.

An existent delta robot is used which needs to be modified to adapt to the soft end effectors.

Moreover, the actuators that control the delta robot need to be replaced.

Once the setup ready, an experimental design is necessary to efficiently compare the soft

manipulators, grasping different objects on the environment, and changing the inputs such as the

pressure used to activate it.

REFERENCES

R. Sukthankar, R. Stockton, M. Mullin, 2001, "Smarter presentations: Exploiting homography in

camera-projector systems", Proc. IEEE Int. Conf. Computer Vision.

J. Hughes, U. Culha, F. Giardina, F. Guenther, A. Rosendo, F. Iida, 2016, "Soft manipulators and

grippers: A review", Frontiers Robot. AI, vol. 3.

.


SYNOPSES E2: Biomaterials 2

Modelling the Deformation Behaviour of Porous PHBV Bone Scaffold Implants

under Compressive Stress

Rushabh PATEL

Supervisors: Prof H. Huang, Dr M. Lu

Annually, there are more than 2 million bone grafting surgeries being performed worldwide [1],

some of which may require the removal of the implants, potentially weakening the bone. Any foreign

object in vivo possesses risks such as immune rejection which is also the major concern for synthetic

bone grafting [2]. Porous metal scaffolds have been extensively studied, but due to their inability to

safely degrade, the potential for toxic metal ions to be released into the bloodstream is a great

concern [3]. The state-of-the-art approaches rely on the use of biocompatible, biodegradable and

bioresorbable scaffold as a blueprint for cells to migrate, colonise and accelerate tissue regeneration.

Poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) is a type of bio-polymer that is biodegradable

and has superior mechanical properties compared to other polymers of its type, which makes it a

prime candidate for use as scaffolds [4]. Porous PHBV scaffolds with completely interconnected

pore network can be made using selective laser sintering (SLS), an additive manufacturing technique

that enables the fabrication of scaffolds with customized shape [5, 6]. Increasing porosity is often

associated with increase in tissue ingrowth and cellular activity. Study shows there is a non-linear

relationship between mean pore size of a scaffold and cell attachment, with larger pores resulting in

significantly more inhabited cells [7]. However, the structural integrity is compromised with larger

pore size which consequently increases the number of weaker regions in a scaffold due to the

thinning of the connecting “bridges”. The thinner bridges are susceptible to breakage at lower

stresses and can potentially cause an inflammatory response as well as disrupt and prevent cellular

growth in the region. Due to the high complexity of the scaffolds the identification of the weak

regions is difficult. This study involves developing a 3D model from micro computed tomography

(µ-CT) scans and utilising Finite Element Analysis (FEA) to model deformation of the scaffold. The

FEA simulation is validated by matching the Young’s Modulus obtained using uniaxial compression

tests. By simulating the real-time behaviour of scaffolds, the need for in-situ observations is

eliminated which helps fabricate a scaffold that is both, strong and porous enough to promote cellular

growth.

REFERENCES

1. Polo-Corrales, L., M. Latorre-Esteves, and J.E. Ramirez-Vick, Scaffold Design for Bone

Regeneration. Journal of nanoscience and nanotechnology, 2014. 14(1): p. 15-56.

2. Roberts, T.T. and A.J. Rosenbaum, Bone grafts, bone substitutes and orthobiologics: The

bridge between basic science and clinical advancements in fracture healing. Organogenesis,

2012. 8(4): p. 114-124.

3. Dabrowski, B., et al., Highly porous titanium scaffolds for orthopaedic applications. Journal

of Biomedical Materials Research Part B: Applied Biomaterials, 2010. 95B(1): p. 53-61.

4. Wu, A.C.K., et al., Reduction of the in vitro pro-inflammatory response by macrophages to

poly(3-hydroxybutyrate-co-3-hydroxyvalerate). Biomaterials, 2006. 27(27): p. 4715-4725.

5. Duan, B., et al., Three-dimensional nanocomposite scaffolds fabricated via selective laser

sintering for bone tissue engineering. Acta Biomaterialia, 2010. 6(12): p. 4495-4505.

6. Duan, B. and M. Wang, Customized Ca–P/PHBV nanocomposite scaffolds for bone tissue

engineering: design, fabrication, surface modification and sustained release of growth factor.

Journal of The Royal Society Interface, 2010. 7(Suppl 5): p. S615-S629.

7. Murphy, C.M., M.G. Haugh, and F.J. O'Brien, The effect of mean pore size on cell

attachment, proliferation and migration in collagen–glycosaminoglycan scaffolds for bone

tissue engineering. Biomaterials, 2010. 31(3): p. 461-466.



Innovative Wound Closure Devices

John K. YAP


Conventionally, sutures are the most commonly used means of wound closure (Praveen, 2009).

These common wound closure techniques such as sutures or staples involve the puncturing of skin.

Suturing processes can be tedious for surgeons and have potential to lead to non-desirable scarring

for patients. To address the problem of tedious and invasive procedures, a non-invasive wound

closure technique is to be investigated.

The goal of this project is to implement design and manufacturing methods to further develop an

innovative wound closure device that has already been in development. The potential and capability

of the product to support business growth and achieve high value production within the medical

industry is to be investigated. Surgical technique used to close a given wound depends on the force

and direction of tensions on the wound, the thickness of tissues to be opposed and the anatomic

considerations (Kudur et al, 2009). The wound closure device investigated in this project is to be

implemented as post-operative care within the laparoscopic surgical procedure.

To become accustomed to making modifications and decisions to the design understanding

background knowledge was essential, therefore a series of information was investigated. This

information included, wound closing mechanics, laparoscopic surgical procedure, existing wound

closure techniques, biocompatible polymers, manufacturing processes, biocompatible adhesives and

prior project work.

Based on previous project work on the wound closure device, it was discovered that nylon was

selected as the material. To evaluate the material properties of the nylon selected, tensile and

compression tests were conducted under different temperatures. It was found that the yield strengths

and strain before failure changed as the ambient temperature of the test conditions were modified.

Prior project work also revealed that a design had already been developed, however problems with

this design occurred when adhesive testing was conducted. It was found that the adhesive would

creep off the wound closure device when bonded onto porcine skin. This problem was either due to

the bonded surface area being too small or the strength of the adhesive selected. Therefore, new

design configurations have been created to increase the bonded surface area as well as address the

adhesive failure.

As the project continues, task to be done are to further investigate different design configurations and

begin testing the designs with adhesives applied onto porcine skin. Once observations have been

made, potential manufacturing methods, cost analysis and comparisons to current wound closure

techniques will be made to address the market potential of the new product.

REFERENCES

Praveen, S (Healthcare) 2009, Suturing Methods Ahead of Advanced Closure Techniques – A Wound

Closure Industry Perspective, Frost & Sullivan Market Insight, viewed 18 April 2018,

<http://www.frost.com/prod/servlet/market-insight-print.pag?docid=165188459>

Kudur, M. H., Pai, S. B., Sripathi H., Prabhu, Smitha 2009, ‘Sutures and suturing techniques in skin

closure’,Indian J Dermatol Venereol Lepro, vol. 75, issue 4, pp. 428-429.



Improving the Corrosion Resistance of Bio-Compatible Mg Alloy with HA

Coating

Yueyao XIAO

Supervisor: Prof Matthew Dargusch, Dr Zhiming Shi Nowadays, as a common bio-compatible metal, magnesium (Mg) alloys caught great attention by researchers.

Mg alloy is a kind of popular biomedical metal applied in the healing of hard-tissue and bone. The corrosion

resistance of Mg alloy using in medicine is the main problem to focus on. Therefore, to improve the corrosion

resistance of Mg alloys, the hydroxyapatite (HA) coating was used in vitro experiment. The corrosion

resistance of the HA coated Mg alloy was tried to improve in this project.

For improving the corrosion resistance, hydroxyapatite (HA) coating was applied on the surface. On the basis

of the previous research, the morphology of pure Mg sample has been found. So the HA coating was applied

on three kinds of magnesium alloys, pure Mg WE43 and EV31, and evaluated in in Hanks’ solution.

The goal of this project was to improve the corrosion resistance of different kinds of Mg alloys applied with

HA coating. If possible, the process of forming HA coating on Mg alloys can be optimised.

The polished Mg alloy samples (about 15*15*5 mm cuboid) were used as the foundation. The specimens were

immersed in Hanks’ solution to form HA coating on Mg alloys and put them all in a water bath at the

temperature of 40℃. The temperature of 40℃ could simulate the conditions in human body and accelerate the

coating growth. The immersion periods were 1d, 2d, 3d, 5d, 7d, 9d, 11d, and 14d.

The morphology and chemical composition of the HA coating on Mg alloys were tested by scanning electron

microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX). In electrochemical tests,

electrochemical impedance spectroscopy (EIS) was used to test the electrochemical properties. Coated

samples were immersed into Hanks’ solution. A standard three-electrode system was utilised consisting of the

coated Mg alloy sample as the working electrode, a saturated Ag/AgCl/KCl reference electrode, and a

platinum counter electrode.

Furthermore, I will cut the coated samples and polish. After that, the morphology and chemical composition

of HA coating on the cross section can be observed with SEM and EDX.

The morphology and chemical composition of HA coating of pure Mg, WE43 Mg alloy, and EV31 Mg alloy

can be observed with SEM and EDX. The morphology of different Mg alloy coating is similar and it changed

with time. There are different kinds of defects on the Mg alloy coatings. They might be caught by abscission

of the coating, the vacuum environment in the SEM machine, the impurities (like Fe, Cu etc.) in Mg alloys, or

the escape of hydrogen.

REFERENCES

Michael C CHAN 2015, The Investigation of Selected Process Parameters on Synthesising Calcium-

Phosphate Coatings for Controlling Magnesium Corrosion in Simulated Body Fluids, Be/ME thesis, The

University of Queensland.

Yueyao Xiao 2017, Improving the corrosion resistance of bio-compatible Mg alloy with HA coating, Be/ME

thesis, The University of Queensland.



Comparison of Corrosion of Magnesium, Iron and Zinc in Air and Simulated

Human Condition

Yaxin. ZHENG

Supervisor: Prof M.S. Dargusch

In clinical treatment, during the reconstruction of human tissues, metal implants are required to be

temporarily implanted and then safely degraded. Therefore, metal materials need to corrode at a

certain rate. Metals that are harmless to the human body and have suitable physical and chemical

properties are likely to become temporary medical implants, this is a new class of bioactive

materials.

Magnesium, zinc and iron are three very promising metals. This project tests the corrosion rates of

pure magnesium, iron and zinc, including static testing and dynamic simulation of human body fluid

environmental, and then evaluates their respective corrosion performance and biological toxicity.

Three clean cubic blocks of pure magnesium, zinc, and iron were used in the experiment. Hank's

solution was used as the electrolyte, and the corrosion experiments were conducted in air

environment and under three different gas atmosphere conditions. The oxygen partial pressure of the

three experiments is 190 ml/L, 180 ml/L and 170 ml/L, respectively. And it is controlled by changing

the partial pressure of air, nitrogen and carbon dioxide.

The electrochemical impedance spectroscopy (EIS), open circuit potential (OCP) and PC data of

these three metals in air environment were obtained. Some experiments are still in progress. Data

from the completed Tafel simulation shows that both the polarization potential and the polarization

current density of pure iron are slightly larger than that of zinc under the same external conditions.

Because the applied potential is the same, it means that the corrosion potential of iron is higher than

that of zinc. This shows that iron is less active than zinc and is less likely to corrode. However, the

magnitude of the corrosion potential can only indicate the possibility of reaction, it cannot explain

the severity of the reaction in the long run. When Hank’s solution is used to simulate body fluids, the

iron reaches the required energy for corrosion and the corrosion current density of iron is greater than

that of zinc. The corrosion rate is proportional to the corrosion current density (Jones 2014), so the

corrosion rate of iron is faster than zinc and magnesium. The data shows that when applied to the

medical field, the corrosion rate of iron is closer to the recovery rate of the human body, which

means that iron and iron alloys have the potential to be applied to clinical treatment. The blood

oxygen concentration of the human body is different in different circumstances, the blood oxygen

concentration of people of different ages is not the same, so it cannot be generalized, the subsequent

experiment will reveal the effect of gas atmosphere on the corrosion of these metals.

REFERENCES

Jones, 2014, Principles and prevention of corrosion 2nd edn, Harlow: Pearson Education.



Polymer Coating on Biodegradable Magnesium Alloy

Yuan XIE

Supervisor: Prof Matthew Dargusch

Magnesium alloys are very potential materials in bioresorbable scaffold (BRS), as magnesium is

biocompatible and its initial mechanical behavior is competent as a stent (Zhang et al., 2013).

However, magnesium alloys normally show a weak performance in their degradation resistance. In

order to improve the degradation resistance of this kind of material, polylactide (PLA) coating is

considered as a method (Puskas et al., 2009). PLA is a kind of biodegradable polymer material,

which is more resistant than magnesium alloys. PLA can slow down the process of magnesium

substrates contacting the corrosive liquid.

My project focuses on the different performance of the PLA coating films on pure magnesium

substrates, by applying different process parameters in dip coating. Coating solution is prepared by

dissolving small PLA balls in dichloromethane. The main parameters include solution concentration,

withdraw condition, drying method and surface pretreatment. I chose different PLA concentrations

(3 w%, 5 w% and 8 w%) to test the influence of coating film performance. In terms of withdraw

conditions, samples are vertical pulled out under stirring and without stirring conditions. When not

stir the samples, fast and slow withdraw speeds are applied. For drying methods, natural drying in a

vertical state and manual controlled rotating drying are tested in 5 w% and 8 w% concentration

coating samples. Surface pretreatment represents if the magnesium substrates are pretreated by

dipping in dichloromethane before coating in PLA solution. The performances of the PLA coating

films are characterized by electrochemical impedance spectroscopy (EIS), optical microscope and

scanning electron microscope (SEM).

The concentration of the solution shows a great impact on the film thickness and degradation

resistance. Withdraw conditions affect the surface quality and sagging performance. Drying methods

have an influence on the distribution uniformity of the film. Surface pretreatment shows no

significant impact on the coating behavior.

REFERENCES

Puskas, J. E., Muñoz‐Robledo, L. G., Hoerr, R. A., Foley, J., Schmidt, S. P., Evancho‐Chapman, M.,

& Haugstad, G. (2009). Drug‐eluting stent coatings. Wiley Interdisciplinary Reviews: Nanomedicine

and Nanobiotechnology, 1(4), 451-462.

Zhang, Y., Bourantas, C. V., Farooq, V., Muramatsu, T., Diletti, R., Onuma, Y., & Serruys, P. W.

(2013). Bioresorbable scaffolds in the treatment of coronary artery disease. Medical Devices

(Auckland, NZ), 6, 37.



Electroplating Zinc on Magnesium as a Biodegradable Material

Zihao Fu

Supervisor: Prof Matthew Dargusch

Magnesium has long been deemed as a revolutionary bio-material for its great biocompatibilities and

mechanical properties. The biodegradability of magnesium makes it an ideal choice for implant

material. However, the bio-corrosion of magnesium is too rapid, the implant would degrade before

the tissue fully recovers (H.Hornberger and S.Virtanen 2012). Zinc, as another biodegradable

material, has a degradation rate which is below the benchmark to be ideal. This project studies on the

feasibility of electroplating zinc on magnesium to meet the standard requirement as a biodegradable

material. Several electroplating processes were adjusted and tested to avoid the involvement of toxic

elements like heavy metals and aluminum which were used in some conventional electroplating

methods.

The project started with a literature review which verified the feasibility of this idea and then

practical research was carried out. The substrate material, pure magnesium, was polished by #1200

abrasive papers and rinsed. Several pre-treatment for electroplating was used to remove the oxides

and hydroxides as well as activate the surface. The pre-treatment includes pickling in chromic acid

solution, activation using phosphoric acid and zinc immersion. Four formulas of zinc electroplating

solutions was used: zinc sulfate solution, zincate solution, pyrophosphate zinc plating solution and

hydrofluoric acid zinc plating solution. Hull cell test was used to determine the best current density

for the electroplating. The PH of the solutions and the time of electroplating are also controlled as

main parameters of the process. The samples after being electroplated was rinsed and dried. The

surface appearance was observed and the component of the plating layer was determined by

metallographic microscope and SEM.

The project research results are listed below. The pre-treatments are crucial for the zinc

electroplating on magnesium, zinc immersion can improve the adhesion of the plating layer to obtain

a better surface, phosphoric activation is effective yet a residue of corrosion products were observed.

The proper current density for zincate solution electroplating was 4 A/dm2, yet the plating zinc layer

is always dark, porous, spongy and non-uniform in all conditions, indicates some additives are

needed. The zinc sulfate solution using a current density of 3 A/dm2 can obtain zinc layers for a

thickness of several micrometers, yet the corrosive effect of sulfate ions is destructive for the

uniformity of the surface. The pyrophosphate zinc plating solution and hydrofluoric acid zinc plating

solution are better yet the uniformity and adhesion strength are difficult to attain without additives.

The analysis shows the corrosion of magnesium substrate and the oxides/hydroxides layers formed

repeatedly and quickly are the main reasons why the electroplating results are not ideal. Future

research directions should be to develop more effective pre-treatments.

REFERENCES

Hornberger, H & Virtanen, S 2012, Biomedical coatings on magnesium alloys – a review, Acta

Biomaterialia.



An Investigation of the École Centrale Paris (ECP) Plasma Torch

Jack T. O’BRIEN

Supervisor: Dr R.J. Gollan

During atmospheric entry of a space probe, a detached bow shock wave is created as atmospheric

gases are compressed against the forward facing nose. Inside this shock wave, kinetic energy

dissipates into the shock gases through intermolecular collisions, increasing the gas temperature

significantly and leading to equilibrium and non-equilibrium plasma conditions. Designing space

probes for these non-equilibrium conditions is complicated because the non-equilibrium kinetic rates

are not well known. As such, ground based experiments are performed to better quantify the non-

equilibrium plasma kinetics.

There are numerous facilities globally which simulate these entry conditions. One such facility, the

University of Queensland’s X2 Expansion tube, creates high energy shock waves which interact with

test models and allow for simulation of complex shock phenomena. However, these shock conditions

are only sustained for a matter of microseconds, and therefore, provide a lack of data on long term

heating effects. Conversely, Inductively Coupled Plasma (ICP) torches sustain high temperature

plasma flows for durations sufficient for investigating surface heating effects. The heating of the

gases occurs through induction heating, whereby an axial magnetic field is produced by a radio

frequency passed through copper coils. This resulting plasma is used to simulate the local

thermodynamic equilibrium effects experienced in the boundary layers of entry vehicles.

In their conventional operation, ICP torches are only useful to study equilibrium plasmas. Laux

(1998) attempted to modify an ICP torch to induce non-equilibrium flows of a N2-Ar-H2 gas

mixture. This was achieved by attaching a 15cm water cooled testing jacket to the exit of the plasma

torch. A significant disparity between experimental measurements and computational fluid dynamics

simulations was recorded, in the order of approximately 2000K.

The aim of this project was to simulate the non-equilibrium flow of plasma from the modified torch

using a modern computational fluid dynamics package, namely, Eilmer4 (Gollan & Jacobs 2013).

Works to date show that it is possible to simulate the torch, with preliminary investigations following

a systematic process of developing the model geometry and flow state conditions, before

incorporating a 10 species, 14 reaction finite rate gas model for the N2-Ar-H2 gas mixture. Results

show that steady state conditions are achieved in the simulations. Data extracted from the flow

solution at the test section outlet have been compared to experimental results.

Preliminary results show that a disparity is still occurring between the experimental and simulation

results. The remaining weeks of the investigation will focus on exploring what high temperature gas

effects or heat transfer mechanisms may be absent and attempting to implement these into the

simulation model.

REFERENCES

Gollan, R. J. & Jacobs, P. A., 2013. About the formulation, verification and validation of the

hypersonic flow solver Eilmer. International Jounral for Numerical Methods in Fluids, 73(1), pp.

19-57.

Laux, C. O. et al., 1998. Numerical Simulation of Nonequilibrium Nitrogen and Air Plasma

Experiments. American Institute of Aeronautics and Astronautics, Issue 29th AIAA,

Plasmadynamics and Lasers Conference.



Developing a High Strength Titanium Alloy

Xiao MA

Supervisor: Dr Michael Bermingham

In the recent years, titanium alloy has increasingly been used as construction parts in the

aviation industry due to the excellent properties. It is known for high strength, high heat

strength, good corrosion resistance and performance in low temperature (Leyens &Peters, 2003).

Some high- strength titanium alloy has even better strength than alloy-structure steels, which is the

reason for its use on aircrafts and rockets.

However, the machining ability of titanium alloy is relatively poor, meaning that it is

complicated to produce complex-shaped structural parts by conventional manufacturing and

machining. Besides, conventional method tends to result in waste on raw materials and time.

Therefore, it is reasonable to adopt additive manufacturing(AM) to produce titanium alloy, which

saves time, effort and materials. More importantly, metal AM makes it possible to produce

titanium alloy with complex shapes. In this project, Grade 19 titanium, which is a beta C titanium

alloy, is chosen to be manufactured by metal AM. As no one has done such work on Grade 19

titanium alloy, whether a good mechanical property will be achieved is also a main focus.

Therefore, we made some Grade 19 titanium alloy samples by metal AM and divided them into

groups. Then heat treatment was adopted in different temperature from 500℃ to 575℃ and

duration from 1h to 8h, from which different mechanical properties were achieved

(Ankem & Greene, 1999). Next hardness test was done to obtain the information how hardness

changes with different heat treatment. Finally, we looked into the microstructure of samples with

particular figures and determined the reason.

Additive manufacturing provides a new pathway for delicate construction parts with complex

shapes. If metal AM titanium alloys are appropriately heat treated, they are able to satisfy the

needs which conventional manufacturing methods cannot.

REFERENCES

Leyens, C., & Peters, M. (Eds.). (2003). Titanium and titanium alloys: fundamentals and

applications. John Wiley & Sons.

Ankem, S., & Greene, C. A. (1999). Recent developments in microstructure/property relationships

of beta titanium alloys. Materials Science and Engineering: A, 263(2), 127-131.



Understanding the Influence of Paint Baking on the HE Susceptibility of Some

AHSS

Suyu ZOU


Due to the formability and high strength, the advanced high strength steels (AHSS) have been

utilized wildly in auto industry. However, the H2 produced by general or crevice corrosion of the

steels can be introduced into the car body causing hydrogen embrittlement (HE) during auto

service.[1-3] Recent studies which were conducted under simulated service conditions and tested the

steels at different hydrogen fugacity conditions have come to an conclusion of HE susceptibility of

different AHSS including twinning-induced plasticity (TWIP), martensitic (MS), quench and

partition (QP), and dual phase (DP) AHSS. The researchers studied the role of H2 trapped in steels

causing HE, and the influence of H2 on steels’ mechanical properties and fracture mode.[1, 4]

However, what has not been tested is the influence of the thermal treatments on HE of AHSS,

especially annealing. The current work fills in the gaps of the influence of paint baking on the

influence of HE susceptility on TWIP, QP and DP AHSS using Linearly Increasing Stress Test

(LIST).

This study mainly focuses on the influence of H2 by discussing the change of ductility, yield strength

and the ultimate tensile strength of three AHSS: TWIP950, DP980 and Q & P980. After annealing at

180℃ for 30min, the specimens are exposed to four particular environments respectively: i) 3 wt%

NaCl at Ecorr ii) 3 wt% NaCl at EZn (-950mVAg/AgCl) iii) 0.1M HCl at Ecorr iv) 0.1 NaOH at -1100

mVHg/HgO, where the H2 can be introduced into the specimens via electrochemical cathodic charging.

Simultaneously, a linearly increasing stress was applied to the specimen until final fracture of the

steel. The data was recorded and calculated to analyse the changes and influences.

The ductility of all annealed steels exposed in the air is approximately equal to that of the unannealed

ones, while the ductility decreases when the specimens were subjected to specific solutions with

cathodic charging. The ultimate tensile strength and yield strength of specimens in solutions with

cathodic charging are lower than that of the specimens exposed in the air. However, the strength

changes between annealed and unannealed steels are not regular. Besides, the fracture modes change

from ductile cup and cone fracture to more brittle shear fracture for all steels.

REFERENCES

1. Qinglong Liu, Q.Z., Jeffrey Venezuela, Mingxing Zhang, Andrej Atrens, Hydrogen influence

on some advanced high-strength steels. Corrosion Science, 2017. 125: p. 114-138.

2. X. Zhu, Z.M., L. Wang, Current Status of Advanced High Strength Steel for Automaking and

Its Development in Baosteel. Rep Baosteel Research Institute,2007, pp.1–8 (201900).

3. Qinglong Liu, Q.Z., Jeffrey Venezuela, Mingxing Zhang, Jianqiu Wang, Andrej Atrens, A

review of the influence of hydrogen on the mechanical properties of DP, TRIP, and TWIP

advanced high-strength steels for auto construction. Corrosion Reviews, 2016. 34(3).

4. Jeffrey Venezuela, Q.L., Mingxing Zhang, Qingjun Zhou, Andrej Atrens, The influence of

hydrogen on the mechanical and fracture properties of some martensitic advanced high

strength steels studied using the linearly increasing stress test. Corrosion Science, 2015. 99:

p. 98-117.



Effect of Solute Additions on the Microstructure and Mechanical Properties of

High-Entropy Cast Mg-Al Based Alloys

Jingwei HU


Nowadays, running out of fossil fuels are attracting more attentions on finding potential light-weight

materials to replace steels, aluminium alloys and some plastic-based structural materials. Magnesium

with its lowest density among several commonly using metals and its considerable strength to weight

ratio comparing to other metals, has been actively pursued for various industries. Despite of its good

strength and weight properties, magnesium also shows poor high temperature behaviour, low

corrosion resistance and bad plasticity under room temperature. (Morishige et al., 2014, Prasad et al.,

2012) For the existence of disadvantages, magnesium cannot be directly used. Advanced magnesium

alloys are demanded. But for general alloying elements, binary system with magnesium are already

determined and magnesium alloys has multiple addition elements has limited relative study. (Ali and

Zhang, 2017) Thus, this research has focused on a novel approach of high-entropy magnesium alloys

with multiple addition elements and designing of the supplementary heat treatment process.

In this study, Mg-3Al is selected as base system and totally six addition elements (Zn, Ca, Y, Sn, Si

and Ti) are involved to invent these high-entropy alloys. 5 alloys in this thesis with 15 alloys within

the whole project are invented using the orthogonal experiment method. Various level of each

alloying elements are applied through that method. After preparation of these alloys, heat treatment

including solid-solution treatment and age-hardening process are designed. Five different

temperatures in solid-solution with four temperatures in age-hardening process are tested. Refer to

the metallographic picture, the best solid-solution treatment temperature was determined for each

alloy. Base on the solid-solution treatment process, age-hardening tests are executed over a length of

totally 120 hours. Age-hardening curves (hardness-time) are obtained for all alloys under four

temperatures. The effect of six addition elements on the hardness of Mg-3Al alloy are determined

based on the hardness data of final product.

REFERENCES

Ali, Y. & Zhang, M.-X. 2017. Effect of Solutes Additions on the Microstructure and Mechanical

Properties of Cast Mg–Al Based Alloys. In: Solanki, K. N., Orlov, D., Singh, A. & Neelameggham,

N. R. (eds.) Magnesium Technology 2017. Cham: Springer International Publishing.

Morishige, T., Ueno, K., Okano, M., Goto, T., Nakamura, E. & Takenaka, T. 2014. Effect of

Impurity Fe Concentration on the Corrosion Behavior of Mg-14 mass%Li-1 mass%Al Alloy.

Materials Transactions, 55, 1506-1509.

Prasad, A., Shi, Z. & Atrens, A. 2012. Flammability of Mg–X binary alloys. Advanced Engineering

Materials, 14, 772-784.



Research on Effect of Multi-Additions on Hardness and Micro-Structure of High

Entropy Mg Alloy Based on Mg-3Al

Shaowen BAI


Magnesium is a popular research topics nowadays because of its huge potential in manufacturing and

aerospace industry. Magnesium has good casting properties and low density but low strength and

hardness. Binary and ternary Mg alloys are quite common. Our project is to research on a high-

entropy system of Mg-3Al based alloy, investigate the effect of multi-additions on its hardness and

microstructure and try to design a suitable heat treatment route.

My research focuses on 5 kinds of Mg-3Al based alloys with different compositions: Mg-3Al-2Y-

Sn-0.2Si-0.2Ti-0.2Ca; Mg-3Al-2Sn-1.5Ca-Zn-0.5Y-0.2Si-0.1Ti; Mg-3Al-1.5Zn-1.5Y-0.5Ca-0.5Sn-

0.5Si-0.1Ti; Mg-3Al-2Zn-1.5Sn-0.5Ca-0.5Y-0.5Si-0.2Ti and Mg-3Al-3Zn-1.5Y-0.5Ca-0.5Sn-0.2Ti.

Heat treatment takes T6 route, solid solution treatment with quenching as pre-treatment; followed by

aging. In solid solution treatment, it is found that Mg-3Al-2Y-Sn-0.2Si-0.2Ti-0.2Ca has good heat

resistance compare to other groups. According to the microstructure, it is decided that suitable solid

solution treatment for g-3Al-2Y-Sn-0.2Si-0.2Ti-0.2Ca; Mg-3Al-2Sn-1.5Ca-Zn-0.5Y-0.2Si-0.1Ti;

Mg-3Al-1.5Zn-1.5Y-0.5Ca-0.5Sn-0.5Si-0.1Ti; Mg-3Al-2Zn-1.5Sn-0.5Ca-0.5Y-0.5Si-0.2Ti should

be 450°C, and for Mg-3Al-3Zn-1.5Y-0.5Ca-0.5Sn-0.2Ti it is 430°

Hardness and microstructure after T6 will be discussed and shown later.



Investigation on Effect of Multiple Elements Addition on the Properties and

Microstructure of Cast Magnesium Alloys

Peilin LI


Magnesium alloys, as the lightest structural metal and one of the most abundant elements in the

earth, exhibit outstanding performance in some specific aspects compared to other metals, which

makes Mg alloy an attractive choice in engineering applications. Plenty of researches have been

carried out on the metallic elements addition on cast Mg alloys, to find better properties of Magnesium

alloys, and some of the improved available Mg alloys on the market have up to 3 to 4 elements addition.

No research before has studied the high-entropy addition to cast Mg-Al based alloys, therefore, this

project is carried out to investigate the effect of multiple elements addition on the mechanical properties

and microstructure of cast Mg alloys.

From investigation of different elements addition on cast Mg alloys, for the high-entropy variables

experimental design, orthogonal test concept is taken into account, which is a specific approach to

research multi-factors and multi-levels. According to the number of factors and relative levels, designed

orthogonal table is chosen as the test table. Six different elements respectively Zn, Ca, Y, Sn, Si, Ti are

used as addition variables. After casting process, designed solid solution treatment is applied to get the

most suitable heat treatment temperature which is chosen as 430 ℃ for group 11-15. Aging treatment is

designed to be 0, 0.5, 1 , 2 , 5 , 10, 15, 24 ,48 ,96 ,120 hour at 200℃. Then microstructure observation

and properties testing of the Mg alloys is carried out to characterize the test alloy. Hardness will also be

measured using a Leco LV800 hardness testing machine.

To conclude, this project has successfully created a few new type of high-entropy cast Mg-Al based

alloys which have relatively good performance in microstructure displaying after solid solution

treatment. The hardness test to evaluate the mechanical properties will be done on the later stage.

REFERENCES

Yahia AliQiu , Bin Jiang , Fusheng Pan , Ming-Xing ZhangDong. 2015. Current research progress

in grain refinement of cast magnesium alloys. Journal of Alloys and Compounds, 639-531.

BolboacăD.Sorana. 2007. Design of Experiments: Useful Orthogonal Arrays for Number of

Experiments from 4 to 16. Entropy , 198-232.



Influence of Pre-Treatment on Hydrogen Permeability in Martensitic Advanced

High Strength Steels

Yifan WANG


Hydrogen presents in steels, especially the non-hydride-forming materials. In some service

environment, it would be absorbed into the steels and if it combines with the applied stress, the

mechanical properties of the steels will degrade or sudden catastrophic failures will occur. And this

phenomenon is called hydrogen embrittlement (HE)(Liu et al. 2016). HE can result in (i) A reduction

of the yield strength and tensile strength, (ii) subcritical crack growth, (iii) a loss of ductility. The

degree of the HE depends on many variables, which are included temperature, hydrogen

concentration, applied or residual stress, etc(Lynch 2012).

Prior work indicates that it is important to precondition the steel surface by long term by cathodic

polarization at a negative potential. The parameters of the specimen and the level of precharging

potential will influence the hydrogen permeation. Thus, in my test, I measure the permeation current

density as a function of time at -1600, -1400, -1100mV(Hg/HgO). What’s more, I carried out

measurement using different thickness of specimens. The potential and the thickness of the specimen

have different extent of impact on the hydrogen permeation.

REFERENCES

Liu, Qinglong, Qingjun Zhou, Jeffrey Venezuela, Mingxing Zhang, and Andrej Atrens. 2016.

'Hydrogen Concentration in Dual‐Phase (DP) and Quenched and Partitioned (Q&P) Advanced

High‐Strength Steels (AHSS) under Simulated Service Conditions Compared with Cathodic

Charging Conditions', Advanced Engineering Materials, 18: 1588-99.

Lynch, Stan. 2012. 'Hydrogen embrittlement phenomena and mechanisms'.


SYNOPSES B3: Aerospace

Investigation of the X2 Expansion Tube’s Primary Diaphragm Rupture Process

using Light 316 Stainless Steel Foil

Paulo J. ALVEAR FUJII

Supervisors: Prof R. Morgan

Hypersonic ground facilities are currently a great way to create conditions needed in hypersonic

studies and atmospheric re-entry analysis in a laboratory setting. This seminar explores the use of a

hypersonic ground facility, the X-2 Expansion Tube, to investigate the rupture process of the primary

diaphragm using Light 316 Stainless Steel Foils.

The X2 expansion tube consists of a reservoir and compression tube, a shock tube, an acceleration

tube, a nozzle and a test section (Gildfind, 2016). The compression tube and shock tube are separated

by a thick primary diaphragm, whereas, the shock tube and acceleration tube being separated by a

thin secondary diaphragm. This expansion tube is used to of produce hypersonic flow conditions

with high enthalpy flow, high pressures and speeds of 20 km/s. These conditions have led to some

implications in the rupture process of light primary diaphragms. It has been found that the light

diaphragms produce unreliable ruptures as several of them loose small particles that become

entrained with the test flow downstream which can damage the test section or the facility itself.

The investigation will be run, using static and dynamic tests on a selected 316 stainless steel foil

diaphragms to create a reliable and clean rupture such that the diaphragm maintains its original

weight and creates a pedal rupture. These could then be used in future experiments, also help

minimise the small particles in the test flow and possibly use these results to extrapolate the bursts

pressures to create heavier primary diaphragms with the same material properties.

REFERENCES

Gildfind, D., Morgan, R. G., Jacobs, P. 2016, Expansion Tubes in Australia, In: Igra O., Seiler F.

(eds) Experimental methods of shock wave research. Shock Wave Science and Technology

Reference Library, vol 9. Springer, Cham



CFD Design of Square-Cross-Section Nozzles for the Expansion Tunnels

Adeline AUGUSTINE

Supervisor: Dr Peter Jacobs

It has been of major debate revolving the use of square cross-section nozzles as an alternative to

axisymmetric nozzles for the expansion tunnels in ramjet/scramjet engine testing. Square cross-

section nozzles distribute un-cancelled waves along lines parallel to the walls rather than being

focused to a point, whereas axisymmetric nozzles tend to focus any wall disturbance to the nozzle

symmetry planes. Therefore, core flow irregularities resulting from off-design conditions or other

wall abnormalities are not as obvious at the exit plane of square cross-section nozzles compared to

axisymmetric nozzles. Regardless of this advantage, it is uncommon to see expansion tunnel nozzles

designed with square cross-sections. In the early 1980’s, a Mach-6 square cross-section-nozzle was

used in a shock tunnel in NASA Langley Research Centre (Thomas et al, 1989). However, the

performance was poor because it was designed using the method of characteristics and a boundary

layer correction which is invalid in high Mach number flow.

The main aim of the project is to study and design an optimized square-cross-section nozzle contour

for expansion tunnels which produces competently uniform outflow with least deviation from the

desired Mach number at exit plane. The optimized contour is generated using Eilmer4 (a Reynolds-

Averaged Navier- Stokes CFD solver developed by researchers in UQ) coupled with a robust

optimization algorithm. In this project, the axisymmetric Mach 12 nozzle for X3 Expansion Tube (P.

Toniato et al, 2016) is used as the reference to build the initial flow domain, set the nominal inflow

parameters and evaluate the performance of the nozzle.

The methodology of this project was to first create an input script for the solver that defines the

initial and inflow states, flow domain, boundary conditions and flow-solution blocks. The symmetry

of the flow domain was exploited and only one quadrant of the flow domain was modelled to reduce

the complexity of the design. The nozzle contour is a Bezier curve defined by 11 control points. The

simulation was estimated as fully turbulent and turbulence model 𝒌 − 𝝎 was adopted. Simulation of

a fully turbulent flow in an un-optimized square-cross section nozzle is currently underway. The data

extracted from the exit plane shows that the non-uniformity in the core flow is due to high pressure

gradient in the boundary layer of the flow near the wall but an optimized nozzle is expected to

produce a more uniform outflow. A complete optimization process will be undertaken, and the

Nelder-Mead algorithm will be employed to steer the search for the optimum design. Once the

optimization converges, the Mach number, angularity and diameter of core flow at exit plane of the

optimized nozzle are compared with that of X3 axisymmetric nozzle.

REFERENCES

Thomas, S.R.,Voland,R.T. (1989).CFD Simulation of Square Cross-Section, Contoured Nozzle

Flow: Comparison with Data. In 42nd AIAA Aerospace Sciences Meeting and Exhibit, number

AIAA 2004-1137, Reno, Nevada, USA. American Institute of Aeronautics and Astronautics Inc.

P. Toniato, D. E. Gildfind, P. A. Jacobs, R. G. Morgan (2016). Optimisation and Design of a Fully

Instrumented Mach 12 Nozzle for the X3 Expansion Tube. School of Mechanical and Mining

Engineering, University of Queensland



2D Model of Slow Flying Paper Planes

Nathan Hansen LU

Supervisor: Dr Klimenko

Gliders have been used as flying machines all over the world for centuries. These simple aircraft are

used as entertainment and competitively by folding paper into paper planes. Paper planes have three

different forces acting on them as they produce no force, such as thrust, to propel them. These forces

are lift, drag, and gravity.

The slow flight of a particular paper plane with large wings follows a dipping motion as it flies. The

ideal path of this motion can be seen in figure 1.

Figure 1. Flight path of the paper plane being investigated.

A theoretical model was to be created to describe the flight path and forces acting on the paper plane

during its flight. To do this an experiment was conducted where the paper plane would be dropped

from a fixed height, allowing it to carry out the motion. The motion is created due to the change in

velocity throughout the flight. As the paper plane looses momentum and approaches zero velocity, it

starts angling downwards and starts accelerating. With the increase in velocity comes an increase in

lift, allowing the paper plane to level out and fly a more linear path. This cycle continues until the

paper plane hits the ground.

The equations of motion for the paper plane were derived from analysing the forces acting on the

paper plane during flight, and how the forces changed. They were found to be:

Vertical Acceleration:

𝒅𝒗

𝒅𝒕=

𝒗𝟐

𝟐𝝆(𝑪𝒍 − 𝑪𝒅) − 𝒈𝒎𝒔𝒊𝒏(𝜶)

Horizontal Acceleration:

𝒅𝒖

𝒅𝒕= 𝒈𝒎𝒄𝒐𝒔(𝜶) − 𝑪𝒅𝝆

𝒖𝟐

𝟐

Pitch Change in Angle:

𝒅𝜶

𝒅𝒕=

𝒖𝟐

𝟐𝝆(𝒌𝟏𝑪𝒅,𝒗 + 𝒌𝟐𝑪𝒍)

Where g is acceleration due to gravity, m is the mass of the paper plane, ρ is the air density, α is the

pitch angle, v is vertical velocity, u is horizontal velocity, k1 and k2 are experimentally determined

coefficients and Cd,v is the vertical coefficient of drag.

To show that the model accurately depicted the flight path of the paper plane, Python language was

used to create a simulation that would iterate through the necessary equations and plot the velocity,

pitch, and displacement of the paper plane. It was found that the above equations accurately model

the flight path of paper plane in two dimensions.



Validation of Wall Function for Reducing Computational Cost of Wall-

Bounded Turbulent Simulations in Eilmer4

Dimir Y. X. POT

Supervisor: Dr Wilson Chan

Developed in the Centre of Hypersonics, at the University of Queensland, the Eilmer4 (Jacobs

& Gollan, 2016) code is a program for the numerical simulation of transient and compressible gas

flows in both two and three dimensions. Currently implemented in Eilmer4 is Wilcox’s 2006

𝑘-𝜔 turbulence model (Wilcox, 2006). The model resolves large flow gradient in the near-wall

region of the turbulent boundary layer, velocity, temperature, and turbulent quantities. This

requires tight grid spacing near the wall, with the non-dimensionalised normal distance of the first

cell from the wall, 𝑦+, to be less than 1 (Chan et al., 2012). The 𝑘-𝜔 turbulence model requires

the flow field to be solved to the wall. This results in dense grids near the wall restricts the

maximum allowable time step during simulation, causing the simulations to be computationally

expensive.

To circumvent this, a wall function boundary condition presented by Nichols and Nelson (2004)

was implemented. Developed based on coupled temperature and velocity boundary-layer

profiles, the wall function utilises the empirical relationships, Spalding’s unified logarithmic law

of the wall (Spalding, 1961), to represent boundary condition information in the near-wall region,

thus allowing the first point off the wall to be placed further away (𝑦+ > 1). The near-wall region

could then be approximated by larger cells, permitting a higher maximum allowable time step.

A set of test cases were carried out to validate the suitability of Nichols’ wall function for

wall- bounded turbulent simulations in Eilmer4. These includes supersonic and hypersonic flows

over: (1) a two-dimensional flat plate, (2) a backward facing step, (3) a three-dimensional flat

plate, (4) an axisymmetric hollow cylinder.

Current progress showed that the wall function is able to accurately approximate the

development of turbulent boundary layers in two and three dimensions, as well as across flow

separations. Carried out with the 𝑦+ range of 50 < 𝑦+ < 1000, the wall function achieved results

with less than 15% uncertainties, and allowed an increase of the maximum allowable time step by

approximately two orders of magnitude.

REFERENCES

Jacobs, P. A., & Gollan, R. J. (2016). The user’s guide to the Eilmer4 flow simulation program.

Department of Mechanical Engineering Report 2016/20.

Wilcox, D. C. (2006). Turbulence modeling for CFD (Third ed.). La Canada, Calif.: La Canada,

Calif.: DCW Industries.

Chan, W. Y. K., Jacobs, P. A., & Mee, D. J. (2012). Suitability of the k–ω turbulence model

for scramjet flowfield simulations. International Journal for Numerical Methods in Fluids, 70(4),

493- 514. doi:10.1002/fld.269

Nichols, R. H., & Nelson, C. C. (2004). Wall Function Boundary Conditions Including Heat

Transfer and Compressibility. AIAA Journal, 42(6), 1107-1114. doi:10.2514/1.3539

Spalding, D. B. (1961). A Single Formula for the “Law of the Wall”. Journal of Applied

Mechanics, 28(3), 455. doi:10.1115/1.3641728



Design of Large Non Reflected Shock Tube for Radiation Studies

Yen Cherk TEOH

Supervisor: Prof Richard Morgan

In interplanetary space missions, spacecraft entry speed range from 10 km/s – 15 km/s, which is

relatively fast in order to reduce trip times with human payload. Radiant heat transfer becomes the

dominant mechanism in high speed atmospheric entries. The Centre for Hypersonics in The

University of Queensland has developed the X3 free-piston driven expansion tube that helps in better

understanding the gas dynamic flows in those conditions. However, the test facility models fluid

mechanics in hypervelocity flow conditions using ' 𝝆𝑳 ' scaling. In actual case density is not

conserved due to dissociation of atoms at high temperature. Therefore experiments have to be done

at true flight pressure (<10Pa). Since test time is limited due to viscous boundary layer growth,

experiment needs to be done with a large diameter shock tube.

The aim of this project is to assess how modifying the diameter of the shock tube will affect the test

conditions flowing through the tube and the feasibility of constructing a larger diameter shock tube.

The 1D fluid dynamics of the facility from the primary driver down to the shock tube is modeled

using Python programming. Based on Mirels theory in boundary layer development (H.Mirels,

1963), the slug length, test time and Reynolds number can be calculated against different shock

speeds, these are some of the vital test conditions for hypervelocity experiment. The conditions are

calculated based on both Mirels limited case and the case when shock tube has finite length. The

conditions against shock speed at different shock tube diameter is plotted for comparison and to

assess whether there is any improvement as the diameter increases.

Results calculated using the Mirels limited case justifies the theory that conditions improve as the

shock tube diameter increases. However, with a finite-length shock tube, the conditions only improve

up until a certain shock speed. At higher shock speeds the flow will become turbulent and the results

of the conditions will converge regardless of the area change between the secondary driver and the

shock tube. Although through further analysis it was discovered that increasing the length of the

shock tube will make the conditions in the finite-length shock tube case closer to the conditions in

Mirels limited case.

REFERENCES

H. Mirels. 1963, Test Time in Low-Pressure Shock Tubes. The Physics of Fluids vol 6, no 9, pp.

1201 – 1214

UQ. 2013. Centre for Hypersonics – X3 Expansion Tube viewed 17 April 2018

http://hypersonics.mechmining.uq.edu.au/x3



Modeling the Entrance of a Scramjet- Based Vehicle to Space

Eduardo A. URRESTA ALBAN


The small satellite market is continuously growing in our current society due to their various

applications in different sectors, such as: agriculture, energy, civil engineering, oil and gas and

defense (Pelton, Madry et al. 2017). As a matter of fact, the small satellite market is expected to

gather US$7179 million by 2022 (Rycroft 2000). Therefore, the necessity of space launch vehicles

designed specifically to satisfy this need is constantly increasing as well.

Prototyping of such vehicles is associated with large costs, thus an accurate analysis to demonstrate

the efficiency of the system compared to already existing options is a key aspect of the design

process. This investigation is focused on using systems engineering approaches to generate an

analysis tool that compares at least two space launch systems and determines which one is the most

adequate according to the defined system’s requirements. The main purpose of the systems

engineering approaches is to achieve a graphical representation of a highly complex problem and

allowing the understanding of the system’s functional and data requirements. The language used in

model-based system engineering (MBSE) was normalized by using the SysML dialect of the unified

modelling language (UML2).

A stakeholder analysis (Rebentisch, Crawley et al. 2005) showed that: safety and reliability, cost

effectiveness and rapid access to space are the aspects with larger concern among the identified

stakeholders. Along with the requirements derived from the stakeholder analysis, other requirements

were derived from the mission profile, stage separation procedures, thermal limitations and specific

operating parameters of each system.

The two selected vehicles to be analyzed are: a conventional three- stage rocket vehicle and a rocket-

scramjet- rocket system. These two systems were modelled using top down approaches to estimate

costs and other features of each specific system.

Modelio 3.7 Software was selected as the SysML tool to develop the SysML model. Diagrams such

as: activity, sequence, state machine and use case were used to describe the behavior of the systems.

The system’s requirements were defined with a requirement diagram and finally, the structure of the

model was described using: block definition-, internal block-, package- and parametric diagrams,

respectively.

REFERENCES

Pelton, J. N., S. Madry and S. Camacho-Lara (2017). Handbook of Satellite Applications edited by

Joseph N. Pelton, Scott Madry, Sergio Camacho-Lara. Cham, Cham : Springer International

Publishing: Imprint: Springer.

Rebentisch, E., E. Crawley, G. Loureiro, J. Dickmann and S. Catanzaro (2005). Using Stakeholder

Value Analysis to Build Exploration Sustainability. 1st Space Exploration Conference: Continuing

the Voyage of Discovery, American Institute of Aeronautics and Astronautics.

Rycroft, M. (2000). The Space Transportation Market: Evolution or Revolution? edited by M.

Rycroft. Dordrecht, Dordrecht : Springer Netherlands : Imprint: Springer.



An Equilibrium Chemistry Module for the Eilmer4 Flow Simulation Code

Hugh G. MCDOUGALL

Supervisor: Dr P. Jacobs

The UQ’s computational fluid dynamics program, ‘Eilmer’, simulates high temperature gas flows

using a finite volume method. These simulations often need to consider how the fluid composition

varies throughout the flow, something which can be complicated by a lack of reliable reaction rate

data for high temperatures. One solution to this is to idealize the flow to equilibrium conditions,

where each point in the fluid is at local thermodynamic equilibrium. The goal of this project has been

to develop and write a ‘module’ for Eilmer that can calculate these conditions.

In equilibrium flow, each element can be treated as a well mixed system of fixed volume and internal

energy, with a set amount of each atomic element and a well defined temperature & pressure. Under

these conditions, equilibrium is the state that minimizes the total Gibb’s free energy as a function of

temperature and chemical composition (Gordon & McBride, 1994). With this physics established,

the problem simplifies to a nonlinear constrained optimization problem. Two approaches to this

problem were examined and prototyped in python, though only one was found to be reliable and fast

enough to for full development in the Eilmer program.

The well established approach, and the basis of the CEA code that Eilmer currently makes use of, is

to use the method of Lagrangian multipliers, coupled with a Newton Raphson rootfinding method for

the gradient (Zezelnik & Gordon, 1960). This approach was adopted for this project, including its

selection of correction variables and its algebraic reducing of the iteration equation, though the

specific required formulations were made independently. The cost of this method scales with the

number of elements, and is almost independent of the number of chemical species (Blecic et Al,

2015), something well suited to the applications of Eilmer. In testing, this algorithm was found to be

fast, robust, and with the application of successive over-relaxation, well suited to the small

perturbations in input conditions. This method was applied in full to Eilmer.

A second approach was examined in which the constraints were used to reduce the optimization’s

degrees of freedom, providing a bounded solution space in which to apply the traditionally methods,

such as the Nelder-Mead or steepest descent algorithms. The complexity/cost of this approach scales

with the number of chemical species minus the number of atomic species. This approach was found

to have two main drawbacks: (1) its cost scaling was poorly suited to use with Eilmer, and (2) the

tendency of the optimum to lie on or near the solution space boundary caused most optimization

algorithms to perform poorly and respond badly to changing input conditions. The solution space

itself, however, was found to provide a useful way of locating a reasonable starting point for iteration

in the Lagrangian method.

REFERENCES

Blecic, J., Harrington, J. Bowman, M. O. 2010, TEA: A Code For Calculationg Thermochemical

Equilibrium Abundances, University of Central Florida Department of Physics, Orlando.

Zeleznik, F. J. & Gordon 1960, An Analytical An Analytical Investigation of Three General Methods

of Calculating Chemical Equilibrium, National Aeronautics & Space Administration, Washington.

Gordon, S. & McBride, B. 1994, Computer Program for Calculation of Complex Chemical

Equilibrium Compositions & Applications, National Aeronautics & Space Administration,

Cleveland.


SYNOPSES C3: Civil

Beach Erosion at Amity Point

Clara TAVERNE

Supervisor: Dr Peter Nielsen

Amity Point is a small seaside village on Stradbroke Island in Queensland, Australia which includes

a beach characterized by important, rapid, erosive slope failures, also called Retrogressive Breach

Failure. Beinssen et al. (2014) state that this erosion mechanism can occurs when the sand is

compacted and dilatant, the subaqueous slope is very steep, and a trigger event happens to start the

failure. He confirmed the existence of two different dilative failure as You (2013) explained: a slow

constant breaching phenomenon and a dual-mode slope failure, which is a succession of sliding and

breaching events.

Those erosive events are fast, unpredictable, and can cause a lot of damages. In my project, I run

different surveys and experiments at the geomechanics laboratory to understand how parameters

such as wall height, density, hydraulic conductivity and friction angle have a role to play in those

events. I characterised the Amity Point sand and its behaviour but also a heavy black mineral sand

from the south of Stradbroke Island.

Experiments showed that the velocity of the vertical breach wall decreased with the breach height

diminution and the increasing concentration (decreasing porosity). The angle of initial yield, that

means the angle when an avalanche starts spontaneously, increases with the concentration and

depends on the shape and arrangement of sand grains (Allen, 1970b). The hydraulic conductivity

(mm/s²) increases with the porosity, and experiments confirmed previous empirical equation which

linked the hydraulic conductivity to the grain-size distribution of sand (Odong, 2007).

REFERENCES

Allen J.R.L. 1970b, The angle of initial yield of haphazard assemblages of equal speres, in bulk,

Geol. Mijnb. 49, 13-22;

Beinssen K., Neil D.T. and Mastbergen D.R. 2014, Field Observations of retrogressive breach

failures at two tidal inlets in Queensland, Australia, Aust Geomech 49.3: 55-63

Odong J. 2007, Evaluation of Empirical Formulae for Determination of Hydraulic Conductivity

based on Grain-Size Analysis, Journal of American Science, 3(3)

You Y. (2013) Dynamics of dilative slope failure, dissertation, University of Texas at Austin.


SYNOPSES C3: Civil

Tensile Strength Perpendicular to Grain of Timber

Wentao LYU

44459358

Supervisor: Dr Dilum Fernando

Timber, a traditional building material still widely used in modern society, has quite different

properties from other modern materials such as concrete and steel. It has unique and relatively

independent mechanical properties in its three mutually perpendicular axes. (Forest Products

Laboratory, 1999) Tensile strength perpendicular to grain has the least strength among all the

properties of timber and should be avoided in wood structural design. (Henrik Danielsson, 2013.)

Therefore, very limited data regarding this property is provided in present design codes.

This thesis mainly studied the perpendicular to grain properties of standard Australian pine wood.

The experimental part concerns tests on over 200 small clear timber specimens, including tensile

strength perpendicular to grain test, moisture content test and some basic data measurements. The

theoretical part concerns evaluation and analysis of experimental data as well as comparison between

experimental results and data recorded in modern Australian code. The experimental data indicates

that the tensile strength of timber perpendicular to grain is much smaller than that parallel to grain,

which is only 2.0~5.0 Mpa. The experimental results didn’t show any linear or non-linear

relationship between tensile strength perpendicular to grain and moisture content of tested specimens.

From further study, the experimental data collected from more than 200 samples in similar status is

not a strictly normal distribution. Slight differences in slope of grain and natural defects in some of

the specimens can be main factors affecting the experimental results.

In conclusion, the tensile strength of timber perpendicular to grain is generally around 2.0~5.0 Mpa.

This property is only about 1/40~1/30 of that parallel to grain and is significantly affected by slope

of grain and natural defects of timber such as knots and pitch pockets.

REFERENCES

Forest Products Laboratory. 1999. Wood handbook—Wood as an engineering material.

Henrik Danielsson, 2013. Perpendicular to grain fracture analysis of wooden structural elementals

models and applications.

ASTM International, 2015. D143 - 14 Standard Test Methods for Small Clear Specimens of Timber.


SYNOPSES C3: Civil

Application of Limestone and Glass Dust in Concrete Pavement

Enbo KANG

Supervisor: Dr Johnny Ho

To achieve the requirements of the Brisbane City Council that building a sustainable city, this

research is devoted to exploring the sustainability of concrete and applying it to the municipal

pavement. Concrete is the most used artificial materials and vital to human construction. At the same

time, the use of concrete also has a negative impact - a large number of carbon emissions. This is

mainly due to the dependence on cement in concrete. In fact, during the production and use of

cement, huge carbon emissions are accompanied. According to the research, in the production of

cement, around 1 ton of carbon dioxide is produced per ton of clinker (Barcelo L, 2013). This is

determined by the material that generates the cement and the nature of the chemical reaction itself.

Therefore, the development of alternative materials for cement is of great significance. Due to good

performance and lower cost, Limestone and glass dust are considered to be good alternatives.

The project is mainly based on performance testing under different ratios, including slump, strength,

shrinkage, etc., to find an optimal design match with the requirements of the Brisbane City Council.

At the same time, the combination with environmental, cost and some other factors, finally apply it

to the construction of a sidewalk in southeastern Queensland.

In conclusion, the use of limestone can better improve the performance of concrete, and the

comprehensive evaluation of performance, cost, and environmental protection. The replacement ratio

of limestone of 25% is the optimal ratio. Glass dust is used as a substitute for cement. In the case of a

water-cement ratio of 0.5, the replacement ratio of 15% merely satisfies shrinkage requirements. All

ratios failed to meet the strength requirements within the specified time, and the strength of the test

specimens decreased significantly as the replacement ratio increased.

REFERENCES

Barcelo L, B. B. D. A. e. a., 2013. The Five W’s and One H of Portland Limestone Cement (PLC).

35(11): 37-40 ed. s.l.:Concrete international.


SYNOPSES C3: Civil

Leveraging Additional Capacity out of Telstra Mobile Structures

Philip DIETERS

Supervisor Academic: A/Prof M. Veidt

Industry Supervisor: Jim Williams

This thesis is being conducted in unison with the Network Architecture Design (NAD) team within

Telstra. With support from School of Mechanical Engineering and CEED. NAD is responsible for

development of the structural standards within Telstra, ranging from configuration of RF equipment

through to power supply environments.

Over eight months of 2017 research was completed for Telstra by Aurecon to provide an

investigation into possible methods of reducing the effective sail area (ESA) of infrastructure at

height (Aurecon, 2017). This investigation was used to enhance the Telstra design guides and

provide a CFD template to allow for uniform results between contractors. This thesis is an extension

of the research conducted by Aurecon and is aimed at investigating the ESA of three unique head

frames to determine the suitability for future use across the network.

This research will be completed through the construction and testing of scaled models within a CFD

program know as OpenFOAM. OpenFOAM is a free, open source CFD software that has been

developed and released by OpenCFD Ltd (2017). Due to its free licensing it is used widely within

engineering and science fields. In addition, the development of the CFD templates by Aurecon will

be used as a stepping stone to launch into investigations.

Through the methods provided within the AS/NZS 1170.2 the relevant wind speeds will be

determined at location of the first unique head frame design (Australian/New Zealand Standard,

2002). This specific location has been chosen as it is in Brisbane and allows for photographs to be

taken for explanation of relevant multipliers. In addition, by using one location as default to calculate

wind speed this will allow for an easy comparison to be completed for each of the different head

frames. Comparison will be completed using the overall ESA of each of the different structures head

frames and equipment configuration. These three head frames will then be compared to the J1/J2

head frame, this is commonly used throughout the network. This will provide a baseline to determine

if these head frames should be considered for wider used. It is important to note that even if the

unique head frames have a lower ESA at this specific location this will not necessarily be the case at

other locations due to environmental factors.

For each head frame the same equipment configuration will be used to further provide a uniform

footing for comparison. The equipment configuration will be further investigated in the aim of

developing a configuration that will provide an optimum ESA for the equipment in use.

REFERENCES

Aurecon. (2017). Telstra Antenna Shielding Research Project. Adelaide, SA: Aurecon Australasia

Pty Ltd .

Australian/New Zealand Standard. (2002). Structural design actions Part 2: Wind actions (AS/NZS

1170.2:2002). Sydney, NSW: Author.

OpenCFD Ltd. (2017, 12 31). About OpenFOAM. Retrieved from https://www.openfoam.com/


SYNOPSES C3: Civil

Shade Cloth Rollover Project

Graham M. ANDERSON

Supervisor: Prof David Mee

The shade cloth rollover project is a CEED project designed by Anderson Horticulture to enable the

deployment and retraction of shade and hail covering in their avocado tree nursery. The current shade

covering is intensive to remove and redeploy, this limits the trees growth, as different stages of production in

the nursery require different conditions and triggering of plant photoreceptors from incident light. This sub-

objective requires decision on shade cloth density and colour, it is evident that the requirements on

wavelength restriction and maximisation are as follows:

UV (280- 400 nm wavelength) must be kept at a minimum to reduce DNA mutations and

physiological plant process damages (Stapleton, 1992), one such damage is termed photoinhibition,

limiting plant growth (Krause et al., 1999).

Incident radiation is absorbed by plants within the spectrum of 400- 700 nm wavelength (Mupambi et

al., 2018), termed PAR (photosynthetically Active Radiation). Within this range the intensity must be

controlled to 660 mmol m−2 s−1, in order to provide maximum growth for avocados while limiting

photoinhibition (Schaffer and Whiley, 2003).

A peak 530 nm wavelength must be maximised to reduce pest invasion and virus transmission in the

plants (Ben‐Yakir et al., 2012).

The smallest possible Red (640–680 nm): Far-red (690–750 nm) spectrum ratio of incident light will

limit detrimental shoot elongation and flowering (Craig and Runkle, 2013).

The mechanism design is the main objective of this project, an overall covering capable of being actioned in

bench-wise segments has been designed as a prototype, incorporating roller door sliders and spanning 20m x

3m, the maximum dimensions of one bench covering. The scale of this prototype is necessary to develop a

tensioning system to shade cloth specifications and to develop additional support for the weight of the shade

cloth, as it is required to be installed outside of the irrigation zone. A comprehensive design of this project will

be submitted to Anderson Horticulture with a contracted builder and shade cloth supplier recommendations to

follow the construction steps and specifications outlaid in my final thesis.

REFERENCES

Ben-Yakir, D., Antignus, Y., Offir, Y. & Shahak, Y. 2012. Colored shading nets impede insect invasion and

decrease the incidences of insect‐transmitted viral diseases in vegetable crops. Entomologia Experimentalis

et Applicata, 144, 249-257.

Craig, D. S. & Runkle, E. S. 2013. A moderate to high red to far-red light ratio from light-emitting diodes

controls flowering of short-day plants. Journal of the American Society for Horticultural Science, 138, 167-

172.

Krause, G. H., Schmude, C., Garden, H., Koroleva, O. Y. & Winter, K. 1999. Effects of solar ultraviolet

radiation on the potential efficiency of photosystem II in leaves of tropical plants. Plant Physiology, 121,

1349-1358.

Mupambi, G., Anthony, B. M., Layne, D. R., Musacchi, S., Serra, S., Schmidt, T. & Kalcsits, L. A. 2018. The

influence of protective netting on tree physiology and fruit quality of apple: A review. Scientia Horticulturae,

236, 60-72.

Schaffer, B. & Whiley, A. Environmental regulation of photosynthesis in avocado trees–a minireview. Proc.

V. World Avocado Congress (Actas del V Congreso Mundial del Aguacate), 2003. 335-342.

Stapleton, A. E. 1992. Ultraviolet Radiation and Plants: Burning Questions. The Plant Cell, 4, 1353-1358.


SYNOPSES C3: Civil

BIM-Based Application Framework for Construction Lifecycle Management

Zhongying DU

Supervisor: Dr SangHyung Ahn

Construction industry exerts a significant role in Australian economy by accounting for 21 percent of

GDP in 2016 (Australian Bureau of Statistics). However, opposite with the great economic

performance, construction industry in reality has an inferior record in productivity and safety control.

Statistically, 98 percent of mega-construction projects are confronted with overruns or

postponements (Changali, Mohammad & Nieuwl, 2015). Moreover, in the rank of the most

dangerous work in Australia, construction is rated as the third risky industry (SafeWork Australia,

2016). The primary causes leading to the situation are inferior project management and insufficient

use of digital technologies. Building Information Modelling (BIM), as an interruptive technology in

the construction industry, aims to maximise profits, reduce risks, gain sustainability and therefore

provide better project performance through modelling visual representations and sharing,

exchanging, extracting, integrating and managing project information (Eadie, Browne, Odeyinka,

McKeown, McNiff, 2013). This paper will explore the potential BIM function and propose a BIM-

based application framework to construction lifecycle management to achieve productivity

improvement and safety control. It also could be used as an BIM information management model to

allow the information index and delivery.

The first part of the paper is literature review aiming to answer these questions 1) What is the current

construction industry situation in Australia. 2) what is BIM - nD modelling and its characteristics? 3)

How does BIM implement in Australia. 4) What are the principles to improve productivity and safety

performance respectively of construction industry 5) What is the critical information required in the

model 6) How the information delivering among stakeholders impact the project management in

BIM? The second part aims to establish a framework based on the principles of BIM lifecycle

implementation and the objectives of raising productivity and safety performance. In the design

phase, BIM offers building performance analysis and collision detection to conduct decision-making

of stakeholders. In the construction phase, BIM supports project real-time progress and simulation

safety monitoring to ensure construction security and project progress. In the operation phase, BIM

provides facility management and safety monitoring to guarantee the project to operate safely. In

each phase, it contains a five-step lifecycle model to approach to maximise productivity and safety

performance.

In conclusion, this paper proposes a conceptual BIM- based application framework for construction

lifecycle management. It develops potential BIM implementation in construction project and

integrates the construction project information to reach the optimal project management performance

in cost, schedule, risk control, resource allocation and safety improvement.

REFERENCE

Australian Bureau of Statistics. (2016). Australian Industry Report 2016.

Eadie, Browne, Odeyinka, Mckeown, & Mcniff. (2013). BIM implementation throughout the UK

construction project lifecycle: An analysis. Automation in Construction, 36, 145-151.

Changali. S, Mohammad A, & Nieuwl M. (2015). The construction productivity imperative.

Mckinsey & Company.

Safe Work Australia. (2016). Fatality statistics.


SYNOPSES C3: Civil

Determination of the Burning Behavior of a Timber at a Bench-Scale

Qin CAI

Supervisor: Dr Juan Hidalgo Medina

The usage of cross laminated timber increases dramatically as a traditional construction material in

recent years and that is due to the requirements of environmental sustainability of human. The aim of

the project is to access an experimental methodology to estimate pyrolysis rates of timber products

when exposed to fire. The motivation of this work is to propose a methodology that can later be used

to assess the self-extinction of timber structures in compartment fires experiments.

The whole experiment focuses on dividing into two groups, each consisting of a comparative

experiment. One naked timber wrapped with aluminum is placed on the scale to measure the mass

loss when it exposed to heat flux (50KW/m2). Another timber wrapped with aluminum and insulation

materials will place Stainless steel plate on the top which can effectively reduce or eliminated the

oxidation rate. Thermocouples were allowed to be place on different of the block which is used to

measure the temperature. The whole experiment will last for an hour, and the heat flux will change to

10KW/m2 for half an hour after the experiment. Thus, this study is concentrated on record the

temperature and mass change ever second and finally process and analysis the data to acquire the

performance information of timber.

The current results show that self-extinction occurs when mass loss rate is below a certain value. For

self-extinction, the flaming of the timber is achieved by applying external heat flux, self-extinction

occurs when removal the external heat flux, that is due to the timber burning flame is insufficient to

provide the mass loss rate that is required for its continued combustion. The work can provide a test

method to help future timber combustion tests.

REFERENCES

Hidalgo et al., 2016. Methodology for estimating pyrolysis rates of charring insulation materials

using experimental temperature measurements. Journal of Building Engineering, 8, pp.249–259.

Bartlett, A. et al., 2017. Auto-extinction of engineered timber: Application to compartment fires with

exposed timber surfaces. Fire Safety Journal, 91, p.407.

Emberley, R. et al., 2017. Description of small and large-scale cross laminated timber fire tests. Fire

Safety Journal, 91, p.327.



Investigation into the Aromatic Ketene-Claisen Reaction

Jiakun ZHANG

Supervisor: A/Prof Ross McGeary

Nowadays, Claisen rearrangement reactions are widely used in organic synthesis. Claisen

rearrangement reaction provides a new pathway to add functional group, as well as ring expansion,

and its products can be used as intermediates. In addition, in 1978, chemists found that allylic ethers,

sulfides and tertiary amines on treatment with ketenes may conduct a [3+3] sigmatropic shift, which

can lead to ester formation, as well as a new C-C σ-bond.

In this project, ketene-Claisen rearrangement is focused. The Claisen rearrangement reactivity for six

compounds has been examined. The results of the experiment show that three compounds are able to

proceed Ketene-Claisen rearrangement reaction, but the rest three agents cannot react.

In conclusion, it is possible to use Ketene-Claisen rearrangement reaction to generate new

compound, especially ester compounds. Moreover, the reactivity of Ketene-Claisen rearrangement

reaction may be influenced by electronic-withdrawing conjugate and electron-donating conjugate, as

well as the metallicity of reaction center (N, O & S).

REFERENCES

Aggarwal, V., Lattanzi, A., & Fuentes, D. (2002). Ketene Claisen rearrangement of camphor-derived

1,3-oxathianes: Complete control of tertiary and quaternary stereogenic centres. Chemical

Communications, 8(21), 2534-2535.

Burns, Jed. (2016). Experimental and Computational Investigations into the Benzyl-Claisen

Rearrangement. School of Chemistry & Molecular Biosciences, The University of Queensland.

doi:10.14264/uql.2016.456

Mahmood, A. (2017). The steering pathway: Ketene-Claisen rearrangement (KCR)-1978–2016.

Tetrahedron, 73(16), 2173-2190.

Wilsmore, N., & Stewart, A. (1907). Ketene. Nature, 75, 510-510



Pre-Fabricated Folded Structures

Shashank BHANDARY

Supervisor: Dr Joe Gattas

1. Introduction

Prefabricated folded structures is a popular method which is used post natural disasters. It is one of

the effective and low cost construction used for temporary purposes (Gunawarden, et al., 2013).

There are certain benefits from these types of house; rapid construction, low cost, highly efficient,

less time consuming and less manpower. Using mechanical aided workshops software such as auto-

cad and machines like CNC routers, it can easily produce components which is required for

construction of pre-fabricated houses. Furthermore, with the accuracy of these routers, it is possible

to produce highly efficient integral components to attach each parts of the structure with friction less

movement and interlocking system at each joints. The attachments of each joints can be detachable

easily without any skilled labour, hence it can be reused.

2. Methodology

The main objective of this study is to obtain the structural behaviour and strength of these folded

structures. The tests also includes the numerical and analytical analysis of pre-fabricated folded

structures. These tests are mainly focused on thin-walled sections of the structures. Timber is used as

the body material for the structure with square hollow and I sections and FRP is used as the skin for

exterior surface. The structure is built in arch shape with 6 individual arches making a unit. A post

tensioned tie is produced on each ends of the arches to maintain the line of force. These arches will

be gone under uniaxial compression to understand the strength and tension movements of each

joints. The capacities of each arch will be observed till the failure mode occurs. Moreover, the

compression test on these arches give will us the understanding about longitudinal and cross wind

cases which the structure can withstand during wind loading action.

3. Report Scope

Literature review of highly influential origami engineering.

Understanding the structural behaviour of the structure by experimental and numerical

investigations of timber shell structures.

Failure modes of pre-fabricated house.

Developing new strategies and reducing the cost of present structure.

Designing a sustainable house.

REFERENCES

Gunawarden, T. et al., 2013. A holistic model for designing and optimising sustainable prefabricated

modular buildings



Entering the Knowledge Society – A Challenge for Engineering Education Across

the Globe

Student: Lu WANG

Supervisor: Dr Alexander Klimenko

Advanced engineering education (AEE) refers to an enhanced form of engineering education developed to qualify

talented students with capabilities of creating innovative technological changes and scientific revolutions (Klimenko,

2017). The history of AEE can be traced back to the times of French Revolution. Then it was adapted in Germany and

took its modern form in the late 20th century. Particularly designed for the most capable and enthusiastic individuals,

AEE introduces a challenging educational environment radically different to the mainstream engineering education

which is aimed at producing professional engineers. Entering the knowledge society with rapid transformation of

knowledge to perform effective action, the role of AEE is projected to increase. This study explores the major challenges

that different countries face to implement AEE properly and successfully in this knowledge society, and provides some

potential solutions to overcome these difficulties.

The Industrial Revolution led to the rise of engineering profession in the UK. Generally, engineering education in Britain

featured practical skills and failed to support AEE due to the inherently antagonistic view towards the roles of practical

and fundamental disciplines (Smithers, 1993). The Menzies reforms (1950s-1960s) improved the Australian engineering

education system by establishing Colleges of Advanced Education (CAE) and providing financial support to raise the

standards of education and research in universities (Pickersgill, 2005). Nevertheless, the “Dawkins Revolution" in the

1990s cancelled the top segment of industry-orientated programs and other more advanced forms of engineering

education, which consequently decreased the number of engineering graduates with practical orientation. India obtains

AEE capabilities after establishing 5 original Indian Institutes of Technology (IIT) and using intensive education to

acquire high academic standards. The French Revolution brought equality and freedom to the country and promoted the

idea of integrating fundamental engineering education with applied disciplines (Spring, 2012). Facing the problem that

university students are insufficiently exposed to challenging tasks in the real world, a new grand institution has been

established to integrate educational and research strengths. Engineering education in Germany emphasized the

combination of high academic standards and strong practical disciplines in the early 20th century (Angelino, 2003). This

binary system was eclipsed due to the Cold War and the education is highly conservative now. America improved the

engineering curriculum significantly to fulfil the demands for better-qualified engineers to gain a competitive edge in the

arms and space race after WW2 (Mayo, 2007). As a world leader in research innovation, the US attracts the very top

layer of engineering graduates worldwide into the Ph.D. programs. Despite the support from Japanese industry for

education reformation, Japan still needs to modify the tradition to enhance the education system (Goto, 2000). Educating

engineers on a grand scale, engineering education in China is mainly aimed at producing professional engineers and lacks

creative and initiative research programs.

Driven by the dramatic social progress, different countries have introduced diverse policies and reformations to enhance

the engineering education system to satisfy the increasing demand for engineering elites. Some countries need to modify

their traditions to reflect realities of the knowledge-based era. Some require introduction of AEE at undergraduate levels.

And others are supposed to achieve the optimum balance between high academic standards and practical disciplines.

REFERENCES

Angelino, H. 2003. Engineering Education and Professional Development in Germany, France and United Kingdom-

Examples for Establishing Continuing Professional Develop-ment of Engineers in Japan. NII journal, 3, 81-104.

Goto, A. 2000. Japan's national innovation system: current status and problems. Oxford Review of Economic Policy, 16,

103-113.

Klimenko, A. 2017. Notes on advanced engineering education. European Journal of Engineering Education, 1-30.

Mayo, M. J. 2007. Games for science and engineering education. Communications of the ACM, 50, 30-35.

Pickersgill, R. 2005. Dimensions of Innovation: Some Historical Perspectives on Vocational Education and Training and

Innovation in Australia. A Discussion Paper. A National Vocational Education and Training Research and Evaluation

Program Report. National Centre for Vocational Education Research (NCVER).

Smithers, A. 1993. All Our Futures: Britain's Education Revolution. A Dispatches Report on Education.

Spring, J. 2012. Pedagogies of globalization: The rise of the educational security state, Routledge.



Design Review of Temperature & Pressure Relief Valve

Blake A. PHILLIPS


This project is industry based, undertaken on behalf of Reliance Worldwide Corporation (RWC).

Temperature & Pressure Relief (TPR) valves are a compulsory component on every pressurised

unvented storage water heater installed in Australia. RWC have been manufacturing TPR valves with

minimal design changes since 1968. As a result, the valve is securely positioned in the maturity

phase of the product life cycle.

The design review aims to maintain or increase the profit margin by maximising the maturity phase

through modifications to the product and relaunching as a new and improved version. This will be

completed through finding a possible paradigm shift in technology and thereby applying the new

technologies to make modifications to the current TPR valve. This seminar provides an overview of

the design review process undertaken, the changes proposed and the associated performance and

economic benefits.

A bifurcated method was utilised for the review, a quality function deployment (QFD) and a failure

modes and effects analysis (FMEA). QFD has been observed to render highly positive results in

generating customer satisfaction and enhancing market share as well as profits (Akao, 1990, Juran,

1988). FMEA is a fundamental tool, useful in improving reliability, maintainability, safety and

survivability of products (Anil et al., 2014). It was thought that in using these two methodologies

hand in hand, the design review would cover the largest area and result in the greatest benefit.

At conclusion of the FMEA, the failure mode with the highest risk priority number was the valve

opening too early (set pressure loss) due to load loss of the spring. The spring underwent redesign

and the number of coils increased from 7.5 to 7.85 to reduce long term set. The proposed spring was

then endurance tested under the AS1357.1 testing schedule and the set pressure loss was reduced by

22.39%

The QFD analysis determined that the best approach to modifying the valve was to use the current

design and look at component amalgamation and component cost reduction through metal-to-plastic

conversion. Research and development into metal-to-plastics opportunities in the automotive

industry were used due to the similarity in conditions between automotive cooling systems and hot

water plumbing. From this, two components were identified to be amalgamated into one plastic

component and two other components for straight metal-to-plastic conversion. The proposed changes

will result in a cost reduction of the aforementioned valve components of 87.22% and associated

savings per annum of $544,538. Prototypes of these components are currently being manufactured to

be tested under AS1357.1.

REFERENCES

Akao, Y. 1990. Quality function deployment : integrating customer requirements into product design

/ Yoji Akao, author and editor-in-chief ; translated by Glenn H. Mazur ; introduction by Bob King,

Cambridge, Mass., Cambridge, Mass. : Productivity Press.

Anil, M., Anoop, D., Anand, S. & Aashi, M. 2014. Product Development, 2nd Edition, Elsevier.

Juran, J. M. 1988. Juran on planning for quality / J.M. Juran, New York, New York : Free Press ;

London : Collier Macmillan.



Refinement of Occupational Health and Safety Systems in Gelatine Manufacture

Brendan M. JENKYN

Supervisor: Dr I.H. Jahn

An inquisition into Occupational Health and Safety Management Systems (OHSMS) has attempted to identify

and rectify shortcomings in Gelita Australia’s Occupational Health and Safety Management System. The

analysis inspected the fundamental causations which resulted in distinct performance between Gelita’s plants

on a global scale.

The project has aimed to improve occupational health and safety performance through optimized and

targeted improvements to the OHSMS at Gelita Australia.

Gelita Australia was one of the 19 gelatine manufacturing plants owned by the Gelita Corporation that were

examined. Despite similar operation, the facilities had distinct OHS performance. Key performance indicators

included: lost-time incidents/rates, near-miss cases, hazards identified and eliminated and incident severity.

Through 2017, Gelita Australia experienced 3.68 accidents, 15.95 days lost and 1.23 near-misses per one

hundred Full-Time-Equivalent workers. Comparatively, best-practice plants experienced 0.66 accidents, 3.2

days lost and 0.66 near misses per one hundred FTE (Gelita, 2018). To locate and rectify the discrepancies

between plants, four core aspects of the Occupational Health and Safety Management Systems were

considered. These were respectively:

Company culture and societal factors;

Role and utilization of engineering design;

Degree of accountability; and

Comprehension and clarity of safety documentation.

Preliminary research suggested a strong, beneficial correlation with positive company culture and societal

factors and prevention of accidents. In 2017, 60% of the incidents documented at Gelita Australia were

determined to be the result of operators failing to adhere to accepted operating procedures (Gelita, 2018).

Root-cause analysis suggested these incidents were a product of pressure from management and lackadaisical

attitude to OHS. While the profit motive is apparent, it was suggested that the wellbeing of employees has

started to be compromised. Corrective measures included the removal of hazardous substances and frequent

consultation and progress updates.

Reunification of engineering design and occupational health and safety, through the implementation of

controls, has been regarded as one of the most cost-effective methods of hazard elimination. Though

inefficient, a ‘brute-force’ approach has identified two high-risk hazards throughout the project and in excess

of seven severe hazards per month. Observations and analysis of documentation have formed the rudimentary

approach. Cumulatively, the project has resulted in a 500% increase in hazards identified. The project has

identified an appropriate methodology for integrating hazard elimination into the design process beyond

intuition: The core principles the methodology subscribed to were an emphasis on stringent timeline and

accountability.

Contemporary management systems have explored methods of ensuring commitment ranging from incentives

to reprimands: Gelita’s own facilities have previously utilized monetary bonuses. With the rescindment of

these rewards, an appreciable decreased in hazard identification and elimination had occurred. Whether this

relationship is one of causation or correlation remains to be seen.

Analysis has proposed that, despite minor improvement in hazard identification and the methodology for

rectification, the fundamental discrepancies in facility OHS performance are the result of obstinate

perspectives on OHS, a profit preference and even OHS oversaturation.

REFERENCES

Gelita, 2018, Monthly Report: Health and Safety, Gelita, Published 26/01/2018

Gelita, 2018, CAR Register, Gelita, Retrieved 19/02/2018


SYNOPSES E3: Mechanical

Estimation of Intermediate Shapes for Incremental Forming

Joshua A. MONES

Supervisor: Dr W. Daniel

Incremental sheet forming (ISF) is an innovative process of ‘die-less forming’ capable of forming sheet

metal into a variety of three-dimensional shapes (Jackson & Allwood, 2009). Within the manufacturing

industry, there is an economical edge over conventional sheet forming. This is mainly attributed to the

reduced production time, and improved material formability for different applications. ISF utilises a computer numerically controlled working tool that is capable of accurately indenting the workpiece while

following a pre-defined contour path of a designated part (Liu et al., 2014). This allows for incremental

and highly localised plastic deformation of the sheet material until the desired three-dimensional shape is

achieved. However, there are forming limits associated with complex geometries such as steep wall

angles for a single tool pass. Multiple stage forming is implemented to circumvent these limitations

related to excessive material thinning (Verbert et al., 2008). These forming stages can be represented by

intermediate shapes.

This thesis focuses on the estimation of these intermediate shapes by implementing a computational

model that intuitively reverses the ISF process. Initially, from the final design shape, the workpiece

is iteratively ‘flattened’ and deformed until the original state of sheet metal is reached. This model

involves a meshed surface of a specified design shape which applies linear elastic analysis to all

element within the design. Each element then undergoes elastic deformation and this process iterated

to obtain suitable geometric shape forms that can be compatibly used for the multi-stage forming.

The basis of the deformation process is an artificial loading implemented through sets of negative

fractions of forces and moments. Manipulation of the scale for both the forces and moments is

required to address reduction of the local curvature and depth for specific design shapes.

The simulation process will be conducted primarily with ANSYS software which is utilised for the

model design and finite element analysis (FEA), the loading estimation will be incorporated from a

MATLAB script. Different design shapes are investigated to further validate the computational

model. The FEA results will be used to gain an understanding on how complex geometrical features

of specific design shapes impact their respective intermediate shapes.

REFERENCES

Jackson, K, & Allwood, J, (2009). ‘The mechanics of incremental sheet forming,’ Journal of

Materials Processing Technology, vol. 209, no. 3, pp. 1158-1174

Liu, Z, Daniel, W, Li, Y, & Meehan, P, (2014). ‘Multi-pass deformation design for incremental sheet

forming: Analytical modelling, finite element analysis and experimental validation’, Journal of

Materials Processing Technology, vol. 214, no. 3, pp. 620-634

Verbert, J, Belkassem, B, Henrard, C, Habraken, A, Gu, J, Sol, H, Lauwers, B, & Duflou, J, (2008).

‘Multi-Step toolpath approach to overcome forming limitations in single point incremental forming.’

International Journal of Material Forming, vol. 1, pp. 1203–1206



Whole of Life Costing Review for Major Mobile Equipment 2018

Timothy E. G. ROSS

Supervisor: Dr B. Daniel

The “Whole of Life Costing Review for Major Mobile Plant” is a project completed for Downer

Mining, in conjunction with the University of Queensland as part of the CEED Program. Downer

Mining is a civil engineering and contract mining company founded in 1922 (Downer, 2017b), and

as such they submit tenders for the operation of mine site or the maintenance of mining assets.

This project is to review and improve the accuracy of whole of life costs of components on Downer

Mining’s major fleet. The accuracy of life cycle costing is critical to Downer Mining’s core business

and reputation, as it directly effects the tendering process, by giving confidence that all costs

incurred under a contract will be recovered. While seemingly insignificant, the documentation of the

methodology used, and the specific process is a very important and large part of the project as

Downer Mining intends to use this review process for component costing reviews in the future. For

this reason, the process must be explained in detail so that the entire process is clear and most

importantly, replicable.

This project involves: gathering data of the historical costs and life of replacing a component;

processing and cleaning this data; the calculation of the mean historical data; the development of

probability distribution functions for component life at failure; the calculation of economic life; and

the calculation of residual values.

The probability distribution of component life failures is expected to add value for the maintenance

of components rather than costing and it has the potential to be integrated into economic life graphs.

Time permitting, this project will also involve the development of an escalation model for the

component costs. This would involve comparing component pricing trends through previous years

and comparing them to a combination of indices.

After the data is cleaned, the remainder of the process will be done by writing excel macros for a few

reasons. The sheer size of the data set is too large for the statistical methods to be applied to each

component manually and without error. Macro’s also provide a very detailed structure for the entire

process, which allows future users to understand the methodology. Macro’s are also easy to edit and

improve, allowing future improvements to be implemented into the process, and receiving the

updated data within minutes.

The results of this project include estimates for the life of the component, and the costs of small

parts, labour, and the component itself. These results will be compared with existing data and recent

OEM estimates and a recommendation for all costs and lives associated with all components on the

Downer Mining fleet. The reviewed and updated data will be implemented into an ‘economic life

graph’ which shows the total value of the components in the machine over time, increasing as new

components are fitted and decreasing with age. From this, the most appropriate economic life of the

asset can be determined. The economic life ties into depreciation, but ultimately it can be used to

determine the cost to use the asset per-hour. This cost per-hour will be implemented into a database,

in Downer Mining’s estimating software and will be used in future tendering of major mining

contracts.



Sub-Cooled Solar Thermal Plant Modelling

Keyuan ZENG

Supervisor: A/Prof Kamel Hooman

Introduction

Compared with the commercial steam cycle, supercritical CO2 Brayton cycle, considered as an

alternative power cycle, show a clear advantage. Commercial deployment of supercritical CO2

powertrains start with a simple, cyclic supercritical CO2 configuration, but with limited conversion

efficiency over steam-powered systems. A more complex loop configuration takes efficiency

advantages over simple one, especially when the turbine inlet temperature is high (Turchi, 2013). As

a result, the advanced supercritical CO2 cycle design are more likely to improve cycle performance.

Cooling carbon dioxide to the sub-cooled zone can achieve higher work delivered by the fluid as it

expands in turbine, but also increase the compressor's power consumption, which provides a new

idea for improving the circulation efficiency. If the increment of turbine work is greater than the

consumption of compressor, then sub-cooled is valuable.

Detail work

First, try to establish a simple thermodynamic model of Brayton cycle of supercritical carbon dioxide

in MATLAB. The main components of this model are turbine, compressor and heat exchangers. The

turbine process and the compression process are calculated using a constant isentropic efficiency.

Two recuperator process are modelled using pinch point method. The type of cooling tower is natural

drive dry cooling tower modelled based on Kroger (2004). Thermodynamic parameters are

calculated based on REFPROPM (Eric, 2013). After the first step of modelling is completed, the

minimum temperature, compressor inlet temperature, in the cycle is reduced below ambient

temperature. Turbine output pressure is also reduced to adopt temperature change. More heat need to

be rejected due to lower temperature, therefore a refrigerator is added into the cycle and the resulting

change in efficiency value is observed.

Conclusion

Sub-cool can’t increase the supercritical CO2 Brayton cycle efficiency. Although lower minimum

temperature can achieve higher work delivered by the fluid as it expands in turbine, the increase of

power consumed by compressor and refrigerator is more.

REFERENCES

Eric W. L. et al., 2013. NIST Standard Reference Database 23: Reference Fluid Thermodynamic and

Transport Properties-REFPROP, Version 9.1 Natl Std. Ref. Data Series (NIST NSRDS).

Kroger, D.G., 2004. Air-cooled heat exchangers and cooling towers thermal-flow performance

evaluation and design. Volume II, Tulsa, Okla.: PennWell.

Turchi, C.S. et al., 2013. Thermodynamic Study of Advanced Supercritical Carbon Dioxide Power

Cycles for Concentrating Solar Power Systems. Journal of Solar Energy Engineering, 135(4),

pp.041007/1–041007/7.



Design of Hydraulic Bottom-Out Control for Mountain Bike Suspension

Ben J. BRUNCKHORST

Supervisor: Prof P. Meehan

World Cup downhill mountain bike riders race against the clock while descending several hundred

vertical metres on rough terrain over three to five minutes with top speeds up to 80 km/h.

Engagement with World Cup engineers revealed a key opportunity to improve the design of

mountain bike suspension forks by addressing problems associated with “bottoming” the suspension

on harsh impacts. Completely compressing the suspension can cause damage to components, poor

suspension performance and injury to the rider. This design project addresses these issues through

research, simulation, design, manufacture and testing of an adjustable bottom-out damper. Insights

will inform the design of improved bicycle suspension in the future.

Studies have concluded bicycle suspension permits higher speeds over rough terrain by allowing

straight line velocity to be maintained (Orendurff, Fujimoto & Smith 1994) and improving traction

due to a more constant normal force between the tyre and ground (MacRae et al. 2000). The

hydraulic bottom-out device is a damper for the final stage of compression to prevent the fork

bottoming under large harsh impacts, whilst enabling maximum energy absorption over smaller

bumps. These designs are employed in off-road motorcycle and rally car suspension. Due to size and

weight constraints, solutions to address the bottom-out problem for mountain bikes have focused on

modifying the spring component at the upper displacement limit such as using an elastomer

bottoming cone. Such options reduce performance since energy stored in the elastic element must be

subsequently dissipated by the existing damper or rider.

Dynamics of the bike and damper were considered to develop a Simulink model of a sophisticated

mountain bike fork under realistic conditions. The response of the model to a typical impact showed

a reduction in compression amplitude and more stable return to static equilibrium when the damper

was present. The physical design is primarily constrained by size, weight and the requirement to

integrate with existing suspension fork designs. The prototype bottom-out damper was assembled

from existing suspension componentry, a custom CNC machined plate and readily available

fasteners. The device is sealed to withstand rapid changes in the gas and fluid pressures within.

Validation in the field was carried out using high speed video and tracking software. The results

confirm that the hydraulic bottom-out damper decreased full compression events, while reducing

shaft velocity and overshoot on extension. This translates to a more stable dynamic response of the

suspension fork and greater predictability for riders. A hydraulic damper is a feasible and effective

means to address the bottom-out problem and improve performance of mountain bike suspension.

Further testing should be completed to inform future suspension design for downhill mountain bike

racing.

REFERENCES

MacRae, H, Hise, KJ & Allen, P, 2000, ‘Effects of front and dual suspension mountain bike systems

on uphill cycling performance’, Medicine & Science in Sports & Exercise, vol. 32, no. 7, pp.1276–

1280.

Orendurff, MS, Fujimoto, K & Smith, GA, 1994, ‘The effect of mountain bike suspension fork

stiffness on impact acceleration characteristics’, Medicine & Science in Sports & Exercise, vol. 26

(Supplement), pp. S176.



Foot Arch Exoskeleton Design

Marcus B. DALDY


Running shoe designs of the modern era are the result of decades of research and optimisation within athletic

footwear that provide both high performing durability and dynamic movement. Practicality is no longer the

primary concern of shoe manufactures, instead focusing on viscoelastic exoskeletons that can retain more

kinetic energy during the step cycle of an athlete, while maintaining comfort and durability.

To validate and design these exoskeletons, shoe manufacturers must be able to create accurate models for

simulation that can be used for optimisation. Currently, the athletic shoe manufacturing giants who have

access to such dynamic simulations are Nike and Adidas, however their methods for this process are

confidential. The Human Movement School at the University of Queensland (UQ) is currently liaising with

shoe manufacturer Asics to develop their own optimised running shoe.

This thesis investigates dynamic simulation using Digital Image Correlation (DIC) for a running shoe design,

specifically targeting the midfoot region and its corresponding energy retention capabilities. Research

undertaken over the past twelve months stems from proven theories discovered by Dr Luke Kelly, a researcher

from the Human Movement School at UQ, that confirm the foot arch holds a significant amount of energy

during step cycles that running shoes are potentially impeding on by reducing the spring function

contributions from the leg and foot musculature (Kelly et al, 2016).

Before validating a non-linear dynamic simulation, simple compression tests on shoe specimens must be

completed for proof of concept. Matching compression testing stress-strain data with material models using

ANSYS Workbench illustrated the various material properties within the shoe sole that can be stored for

future simulations in a more complex environment.

Compression testing was undertaken on an Asics shoe using a 5 kN loading cell that drove a spherical object

into the specimen to collect the data via cyclic loading. By loading and unloading the specimen over a range

of cycles it could also be observed whether plastic deformation occurs which would impact the chosen

material model. Fortunately, the material behaved mostly elastic which reduces the complexity of the material

model.

A popular material model that evaluates viscoelastic materials is the Prony Series, which is particularly useful

for non-linear cases involving loading and unloading (Chen, 2000). While higher order Prony Series provided

more accuracy, the 2nd order Prony Series was deemed acceptable as validation for the simulation. Subsequent

visual inspection and simulation feedback presented minimal plastic deformation and validated the material

properties.

The next phase of research will involve some type of dynamic movement, such as a step, to create kinetic

energy that can be observed via DIC analysis, which can be used to validate a dynamic simulation built by

ANSYS Workbench. A validated dynamic model provides the foundation for optimisation within the midfoot

arch of the running shoe for higher energy retention.

REFERENCES

Chen, T. (2000). Determining a Prony Series for a Viscoelastic Material From Time Varying Strain Data.

Virginia: NASA.

Kelly, L. A., Lichtwark, G. A., Farris, D. J., & Cresswell, A. (2016). Shoes alter the spring-like function of the

human foot during running. Journal of The Royal Society Interface, 1-9.



Modelling of Complex Competitive Systems Applied to the Study of Technical

Revolutions

Valentine BOUET

Supervisor: Dr A. Klimenko

Innovation is one the main keys that we have to solve today’s and tomorrow’s challenges, not only

economic ones, but also demographical or environmental ones. As engineers we are undoubtedly

involved in this process of creation, but we are also a driving force in it: for that reason, studying

technical revolutions and how they burst from their early days to their decline is essential. This thesis

aims at understanding the pattern followed by technical innovations over the past centuries and its

characteristics, in order to produce an accurate mapping of all industries and simulate their behaviour

as a complex system.

The first part of our work focused on describing the process of technological breakthroughs and their

main characteristics. As explained by Perez (2002), between the 1770s and today we can highlight

five technological revolutions that completely changed our way to produce and consume. When

comparing these five periods, we can see that not only they share the same pattern of development

from one radical innovation to the diffusion into a whole industry, but they are also built through the

same engineering techniques and principles. Another main feature shared is explained by Freeman

and Soete (1997) is the importance of the investment process in the development of a new

technology: it takes into account not only the economic idea of devoting resources, but also the

notion of risks and opportunity gains that can only take place under certain conditions.

The second part of this thesis aimed at building an appropriate model for this complex system

following the methodology presented by Haussman et al. (2011). In response to the non-availability

of their model, we managed to build our mapping of industries by processing international trade data

and grouping products into correlated clusters. This method allowed us to confirm the close

relationships between the production of different elements stemming from the same wave of

innovation. We then intended to introduce the dynamic of investments within this system of

industries: we modelled the diffusion of economic resources by imposing rules copying the different

behaviour of real investments towards existing or new clusters.

With this model, we managed to underline the importance of innovation and its correlation to

economic growth, and understand the processes that build our industrial system as it today. As young

engineers about to graduate at the end of the fifth revolution, that of information technologies and

telecommunication, we can only be looking forward to the next one and make sure that we will be a

part of it.

REFERENCES

Perez, C 2002, Technological Revolutions and Financial Capital: the Dynamics of Bubbles and

Golden Ages, Cheltenham, Elgar

Freeman, C & Soete, L 1997, The Economics of Industrial Innovation, 3rd edn, Routledge, Oxon

Hausmann R, Hidalgo CA, Bustos S, Coscia M, Chung S, Jimenez J, Simoes A & Yildirim M 2011,

The Atlas of Economic Complexity, Puritan Press, Cambridge

School of Mechanical and Mining EngineeringPhone: +61 7 3365 3668

www.mechmining.uq.edu.au

4TH YEAR OF ENGINEERING STUDENT CONFERENCE · 2018-05-01 · 2018 U Q | E N G I N E E R I N G S T U...

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Transcript of 4TH YEAR OF ENGINEERING STUDENT CONFERENCE · 2018-05-01 · 2018 U Q | E N G I N E E R I N G S T U...