Role of Composites for Gradual Improvement of Aircraft Structure

7/28/2019 Role of Composites for Gradual Improvement of Aircraft Structure

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National Institute of Technology, Rourkela

Role of Composites for gradual improvement of

Aircraft Structure

Presented By:

Ajit Behera

Roll no- 210MM1248


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Background

Why composite preferable for Aero-structure ?

Use of Major Composite in Boeing AirplanesDifferent stresses acting on an aircraft

Decline of Cost/weight by Composite

ConclusionsReferences



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Later, the first planes were built with combined construction of wood, fabric, steel andsmall amounts of aluminum for reinforcement. Manufactures used ash and spruce for the

wings which were usually built around two I-shaped spars, and braced either by internal

cables or by forming the leading-edge surface with ply.


Until the 1930s, wood was the primary material used in

aircraft construction. It was plentiful and cheap, had large

bulk and strength for its weight, and could easily be worked

into any desired shape.

After World War-I, builders made the transition for the biplane

configuration to monoplanes. Among the many structural

improvements of this time were the monocoque fuselage and

better metals.

Seamstresses applied to covering the wings with linen, cotton,

or sometimes silk.

In this way demand of composite gradually increased.


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Weight reduction

Challenge in cost reduction

Reduces / Eliminates corrosion

Increases in fracture toughnessLightning protection

Improvements in fatigue resistance

damage tolerance limit increasesStructural integrity (To carry the damage part

load without harming other parts and

operation). National Institute of Technology, Rourkela


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National Institute of Technology, RourkelaStress

Strain


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At Different Time in Year



(E) BENDING (THE COMBINATION STRESS)



Inter-laminar Failure / Delamination / Disbond

Stress concentration such as hole, fillet, also deteriorate strength. It needs additional

thickness= weight

Bolted joint is also a weak point on composite structure

Impact Damage strength regression


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Bolted joints

Doors and windows

System provisions (penetrations and attachments)

Access and drain holes

Attachment tabs

Stringer terminations (run-outs)

Bonded attachments



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Reduction in fuel Cost- Composite contributes light weight than

that of bulk metal and Light weight structure contributes low fuel

consumption.

Maintenance cost- Maintenance cost decreases due to less Bodyideal time (Repairing time), increase in Change interval of

Corroded parts & fractured parts, guarantee for longer inspection

interval etc.

National Institute of Technology, RourkelaFor Boeing787



The application of composite indicates optimal set of

minimum structural weight and manufacturing cost.

However, exposed aircraft surfaces made from composite

materials can prevent problems with respect to its hostile

surrounding atmosphere.

Many investigations have been going on for evolution of new

composite material for future aero-craft structure.



[1]Yin Hailian, Yu Xiongqing, Integration of Manufacturing Cost into Structural

Optimization ofComposite Wings, Vol. 23, Issue 6, 2010, 670-676

[2] Hui Juan Feng, Jian Zhang, Xiang Kai Liu, Applied Mechanics and materials, Vol.

121-126, 1264-1268, 2012.

[3] Ronald F. Gibson, Principles of Composite Material Mechanics, 3 rd edition, crc-press,

Taylor & Francis Group, 53-87, 2012.[4] book review, Glare: History of the development of a new aerocraft Material,

http://composite.about.com/od/books/l/aafpr020623.htm

[5] Joosung Joseph Lee, Historical and Future Trends in Aircraft Performance, Cost, and

Emissions, at the Massachusetts Institute of Technology September 2001.

[6] Alex B. Harman, Chun H. Wang, Improved design methods for scarf repairs to highly

strained composite aircraft structure, Vol. 75, Issue 1-4, 132-144 , 2006.[7] Soderquist, J., "Design/Certification Considerations in Civil Composite Aircraft

Structure," SAE Technical Paper 871846, 1987, doi:10.4271/871846.

[8] R. Kaye, M. Heller, Finite element-based three-dimensional stress analysis

of composite bonded repairs to metallic aircraft structure, Vol. 26, Issue 4, 261-273,

2006.


19/19N ti l I tit t f T h l R k l

Thank you for your attention.

Role of Composites for Gradual Improvement of Aircraft Structure

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