Engineering Integrity Issue 33

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EISENGINEERING INTEGRITY33NOVEMBER 2012

JOURNAL OF THE ENGINEERINGINTEGRITY SOCIETY

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papers on:A "Short" History of Real World Testing (Part 2)

Tyre Noise Measurement - A New Approach (Tyre Cavity Microphone - TMC)

EIS Website: www.e-i-s.org.uk

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ENGINEERING INTEGRITY SOCIETY

INSTRUMENTATION, ANALYSIS AND TESTING EXHIBITIONEntrance to the exhibition & open forums is free to visitorsalong with complementary refreshments

THE SILVERSTONE WING, SILVERSTONE RACE TRACK 12 MARCH 2013 10AM - 4PMOver 50 exhibitors will present the latest advances in measurement and analysis technology in aerospace, automotive, motor-sport, rail, industrial, off-highway, power generation & medical industries. Visitors will be able to discuss these developments & their applications with exhibitors in an informal atmosphere.

Open Forums include:• Residual Strain - Effects & Considerations• Improvements in the Whole Testing & Predictive Process• KERS - Standard & Hybrid Systems• Electric ActuatorsGuest panels comprising industry experts will expand on the technical developments & take questions fromthe floor.

VisitorsIf you are interested in attending please pre-register by emailing [email protected] or visit www.e-i-s.org.uk.

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INDEX TO ADVERTISEMENTS

Amber Instruments ..................................................41Bruel & Kjaer .............................................Back coverBSSM ......................................................................24Data Physics.................................... Inside front coverIMechE ....................................................................41Ixthus Instrumentation .............................................42

ContentsInstrumentation, Analysis & Testing Exhibition, 12 March 2013, Silverstone Race Track ................................................... 3

Index to Advertisements ....................................................................................................................................................... 5

Editorial................................................................................................................................................................................. 7

Technical Paper: A “Short” History of Real World Testing (Part 2) ........................................................................................ 8

Diary of Events ................................................................................................................................................................... 15

Technical Paper: Tyre noise measurement - A new approach (Tyre Cavity Microphone – TCM) ....................................... 16

Call for Papers - ‘Understanding Vehicle Ride Comfort and Seating Dynamics’ ............................................................... 21

How it Works - Testing Using the Concept of Vibration and Resonance ............................................................................ 22

Resonate to Accelerate ...................................................................................................................................................... 23

Innovating in inlets – new technologies to meet emissions legislation for heavy diesel engines ....................................... 25

Industry News ..................................................................................................................................................................... 27

Product News ..................................................................................................................................................................... 32

News on Smart Materials and Structures ........................................................................................................................... 35

News from British Standards .............................................................................................................................................. 36

News from Institution of Mechanical Engineers.................................................................................................................. 37

Group News........................................................................................................................................................................ 38

Membership details ........................................................................................................................................................... 38

Committee Members .......................................................................................................................................................... 39

Corporate Members ........................................................................................................................................................... 40

New Personal Members ..................................................................................................................................................... 40

Front Cover: Courtesy of Bay Systems Ltd

Kemo .......................................................................15M+P International ............................Inside back coverMicro Movements ......................................................4Photo-Sonics International .......................................4Team Corporation ....................................................42Techni Measure .......................................................42

HONORARY EDITORDr Karen Perkins

MANAGING EDITORCatherine Pinder

Anchor House, Mill Road,Stokesby, Great Yarmouth, NR29 3EY

Tel. 07979 270998 E-mail: [email protected]

EDITORIAL BOARDPaul Armstrong

Brian GriffithsDr Fabrizio Scarpa

EIS SECRETARIAT: Sara Atkin

Engineering Integrity Society17 Harrier Close, Cottesmore,

Rutland, LE15 7BTTel: +44 (0)1572 811315

E-mail: [email protected]: http://www.e-i-s.org.uk

EDITORIAL POLICYEngineering Integrity contains various items of

information of interest to, or directly generated by, the Engineering Integrity Society. The items of information

can be approximately subdivided into three general categories: technical papers, topical discussion

pieces and news items. The items labelled in the journal as technical papers are peer reviewed by

a minimum of two reviewers in the normal manner ofacademic journals, following a standard protocol.

The items of information labelled as topical discussions and the news items have been reviewed

by the journal editorial staff and found to conform to the legal and professional standards of the

Engineering Integrity Society.

COPYRIGHT Copyright of the technical papers included in this issue

is held by the Engineering Integrity Society unlessotherwise stated.

Photographic contributions for the front coverare welcomed.

ISSN 1365-4101/2012

The Engineering Integrity Society (EIS)Incorporated under the Companies Act 1985.

Registered No. 1959979

Registered Office: c/o Hollis & Co.,35 Wilkinson Street, Sheffield S10 2GB

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The principal activity of the Engineering Integrity Society, is the arrangement of conferences, seminars, exhibitions and workshops to advance the education of persons working in the field of engineering. This is achieved by providing a forum for the interchange of ideas and information on engineering practice. The Society is particularly committed to promoting projects which support professional development and attract young people into the profession.

‘Engineering Integrity’, the Journal of the Engineering Integrity Society is published twice a year.

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Editorial

The 2012 AGM of the Engineering Integrity Society, together with council and various group committee meetings, were held on 10 October 2012 at the impressive new Control Centre facility at MIRA.

The Society would like to thank MIRA for their hospitality, the use of their facilities, and for their considerable and valuable support of the Society over many years. We look forward to this relationship continuing. It is the provision of this support by companies like MIRA that enables the Society to continue to hold technical events that are of interest and value to engineers at all levels, and within a wide range of disciplines.

NEW ENGINEERING INTEGRITY SOCIETY DETAILS

Please note with immediate effect our change in address and bank details:

Engineering Integrity Society17 Harrier Close, Cottesmore

Rutland, LE15 7BT

HSBC Bank plc, Victory Road, Derby, DE24 9HX Sort Code: 40 - 19 - 37 Account Number: 51692836 IBAN Code: GB46MIDL40 19375 1692836 BIC Code: MIDLGB2128T

If you have any queries please contact:Sara Atkin, Tel: 01572 811315

[email protected]

Welcome to the autumn edition of Engineering Integrity. As the summer slips away we can look back on the Olympics and marvel not only at the physical prowess of the athletes, but also at the technical elements of some of Team GB’s most successful disciplines, such as rowing and cycling. The British Cycling mantra of ‘aggregating marginal gains’ is one that many of us could put to good use, even if L’Equipe found ‘round wheels’ a more

plausible explanation for success.

One of the technical papers in this issue concerns wheels: “Tyre Noise Measurements – a new approach” provides a novel method of monitoring tyre noise on any road surface. The other technical paper, “A Short History Of Real World Testing (Part 2)”, continues from the previous issue with the theme of replicating the real world in a laboratory setting so as to capture the worse case scenario without being hopelessly pessimistic.

In academia another year is well under way, with the new students showing no discernible difference to existing ones despite the new fee regime. While those of us in academia might take some comfort in the fact that the much publicised drop in University entrants this year has largely spared the STEM subjects, the new regime looks to have stalled any increase in the absolute number of graduates for the moment. Of necessity Universities will promote their school liaison schemes and STEM ambassadors will flow out to schools and with the Bloodhound project reaching more photogenic milestones, there should be some good press for Engineers across the mainstream media. With all of these positive messages being sent out and employment rates for Engineering graduates not only up, but amongst the highest for all first degree disciplines, it is slightly worrying to hear in the Industry News section that in a recent survey from Matchtech, over 50% of engineers have lost confidence in government policy towards the industry and that not enough is being done to attract new blood. Seeing so little being done to encourage innovation, many view the UK’s status as a world leader in Engineering as at risk in the future. This is not the sort of message we want our students or prospective students to hear! Indeed there is a dichotomy within the Industry News section, which also reports on several positive developments, in particular investments from the UK government and both home and overseas companies in a range of institutes and innovation centres at UK Universities. These aim to harness the strengths of academia in distinct areas of expertise to push the boundaries of science and offer research support to industry, whether via one off packages of research or more long term research partnerships that include core research and postgraduate study. Perhaps developments such as these are hiding some of the innovation and the support for

innovation from people working in industry who remember when the R&D facilities where on site.

The how it works section moves on from Moog valves in our last edition to talk about vibration and resonance. The section offers us an every day example of how we make use of natural resonant frequencies in mechanical testing and talks about some of the advantages and disadvantages of this technique. As ever, the subject of the environment is never very far away, not only do environmental issues figure significantly in the News from Smart Materials section, the News from the Institution of Mechanical Engineers section features some exciting new concepts in air capture technology and we have an article on air inlet throttle technology.

Karen PerkinsHonorary Editor

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ENGINEERING INTEGRITY, VOLUME 33, NOVEMBER 2012 pp.8-15. ISSN 1365-4101/2012

Technical paperA “short” history of Real World Testing (Part 2)David Ensor, Senior Consultant, MIRA Ltd

This article continues my personal view of durability development and how we replicate the real world. I will remain in the spirit of the Engineering Integrity Society and hopefully describe how things can be done and the pitfalls.

In this second episode, I will cover the methods developed in the 20th Century and onward into the 21st Century. As a spoiler, it is still generally the case that the real world is a notoriously difficult thing to correlate and understand. Accurate durability test and analysis methods for accelerating, reproducing and assessing the performance of a vehicle against a particular event has become quite a science; but little work has been carried out into realistic usage targets.

As a reminder I will pose the same questions for you to truthfully answer yes or no to?

“Can you quote & prove that your design, development or test target actually comes from in the real world?”

“Can you also prove that this represents all users, at the stated extreme condition to a statistical confidence level?”

Recent History (1990’s)

In Episode 1 I described progress up to the 1990’s in real world testing the next decade saw these traditional techniques become established. Techniques still relied upon “long experience” or recreating failures seen from warranty details. I hope I left you with the thought that this is not very satisfactory. The test that only reproduces the failure ‘out in the real world’ makes it too easy to assume that; firstly the same failure mode has been reproduced, and secondly that the test can be applied to other vehicles. This is often far from the truth.

One example that illustrates this point well was on a city bus some years ago. Whilst helping to correlate bus routes to a proving ground a crack problem also occurred at the front of the vehicle. The customer test engineers investigated by testing on Belgian Block Pave as large inputs were assumed to be the problem. Pave did indeed produce similar cracks in the structure after a few days; the engineers then wanted to know how to translate the Pave data to design.

An obvious question had to be asked. “How did they know that they had generated the same failure?” The assumption was that as the same cracks appear on Pave, then the problem must be Pave like input. The reality of the situation is that you do not know that you have created the same

failure mode; it may only have found a weakness for many conditions.

A distance versus fatigue damage analysis was carried out on strain data to provide a gating signal that could be used to review the correlation RLD where damage was accruing. Of course, where large Pave type inputs existed there was damage, but more importantly, damage also occurred outside these conditions.

This surprising result was for a particular down gear change at bus stops producing high vibration. Having now discovered the real problem this enabled us to provide a shorter test using a shaker vibrator into the gearbox mounting. The original investigation would have led to re-tooling the body structure or upgrading materials and maybe not solved the problem.

The lesson learnt was to always test to the real world conditions and that only reproducing the same ‘damage’ does not mean you are seeing the same cause.

As can be seen adopting modern analysis techniques developed in the earlier era’s is the way to save time and provide confidence in results, all due to reproducing accurate ‘real world’ conditions. Even so, questions still remain to be answered. Does this type of test also represent the ‘worst’ design load case for durability? Do particular failure conditions (as above) generate a good proving test? It seemed obvious that this result was particular to this design/system, and it was unclear as to how many of these conditions represent the life of buses in general, rather than a particular route.

Over this decade many of the empirically derived tests established in the earlier eras, had become ingrained in the automotive psyche and used as ‘standards’. For instance the old standards of 1000 miles Pave being equal to 100,000 miles, and using selected road endurance routes to represent the ‘worst case’ user. Many, if not all these durability test standards of the time are prime examples of misplaced correlation. Pave is really just a large ‘random load’ input test from the very early days, where 100 miles was too short, 100,000 too big and a 1000 seems about right and large enough to find early failures and weak spots. Even so, this test can still be somewhat of a challenge, and still survives to this day.

It was during the 1990’s that these embedded standard tests were ‘measured to death’ by engineers such that they obtained their own self-fulfilling prophesy. It was assumed

Parts 1 and 2 have been published under licence from MIRA

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ENGINEERING INTEGRITY, VOLUME 33, NOVEMBER 2012 pp.8-15.

by many that the large amount of data collected must surely mean that they are based on a firm scientific basis. Unfortunately this really is not the case and it is easy to confuse, or even assume the correlation link of successfully producing vehicles that have fewer warranty problems or durability failures, with these empirical durability test regimes, and that the two are the same.

Transition Era (1990’s to 2000’s)

The automotive industry had gained a huge amount of experience in testing from RLD on events, surfaces and especially from failure investigation. MIRA had been using its proving grounds and test rigs along with fatigue & durability theory to reproduce many situations accurately in the lab and even in the virtual environment.

The real advances during this interim period were in the collection of Road Load Data (RLD), a very important requirement of course, advancing the accuracy and efficiency of the development process. But, a major obstacle persisted and went largely unnoticed, there was little done at the design stages to ensure product durability.

Two things became apparent; one that the tools and methods discovered in previous years could also be used to develop very accurate durability test schedules and load cases, and secondly that the industry was hampered by inadequate descriptions of the target life requirements especially in the emerging markets.

Experience had shown that there was a great reliance at

the design stages on keeping the stress/strain levels below ‘the fatigue endurance’ limits for a set of simplified design loads to provide adequate life; the final arbiter then being to test prototypes to discover how long they last. This only leads to time consuming, expensive and iterative proving ground tests.

I would argue that very few, if anyone, in the auto industry designs for durability. It still remains that at the early stages the main criterion is to design for performance, apply a suitable factor of safety to allow for robustness, and eventually having to build prototype vehicles or sub-systems to test, re-design a number of times and re-test, to see if they can survive the test. The following scenario was considered.

Many vehicle manufacturers want longer lives and are extending warranty periods, implying an expected longer life. Suppose that as you are about

design the next new model of your product, a new goal is to increase the warranty period from 100,000 miles to 200,000 miles. This is tantamount to asking to increase life expected by the customer by two.

What in the design process, load cases, or other criteria, can be “factored” by two for this?

No-one had this ‘factor’ or process, and there was a reluctance to double the test period. By designing to a ‘fatigue limit’ the life is expected to be ‘infinite’, or at least well beyond the material cyclic limits. So, the design should already meet both criteria. Obviously, this is not the case.

MIRA set about establishing the actual correlation of the test to the actual usage patterns of the vehicle at the extreme of the distribution of users. At this point in 2000 I was employed to commence the first vehicle usage correlation of China (The subject of EIS presentations).

Collecting RLD to the extent required to establish true usage patterns of vehicles over long periods of time has always proven expensive, difficult, and very time consuming. Some long term data logger developments were discussed in Episode 1. All suffered from lack of time, and statistically verifiable results. In other words the methods take too long.

This limitation meant that the auto industry has concentrated on developing tools aimed at reproducing short term loading from the real world. This means failing to apply these RLD techniques to the more exacting acquisition of usage data and its variation across many users. In many cases

Figure 1: Using real world data to solve the real problem

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PERFORMANCE – ROBUSTNESS – DURABILTY

There are three major engineering goals that a vehicle design has to satisfy & meet the customer’s requirements without over-engineering, excessive costs, or generating problems. A design must meet the performance expected, provide adequate robustness & sufficient life. Performance will get a customer interested in a product, as it is essential that the vehicle does what it is supposed to do & more importantly what you say it does (for instance; 0-6 in 3 seconds, carry 40 tonne, climb a 1 in 2 hill or drive over rocks).

Robustness follows on from performance, because people will accidently (or on purpose) exceed many of these performance criteria. Any customer would expect that occasional accidental abuse should not render the vehicle useless or reduce its performance. Designs should be able to cover moderate excursions outside the design envelope. (For instance: a large pot-hole, accidentally overloading, getting the vehicle stuck in mud).

Durability ensures vehicles do the above for a period expected by the customer, &/or enable her/him to sell on to another user. It is no use supplying a perfectly performing vehicle, which will even allow the odd overload, only for a very short period. True even for special cases like racing – as it is still expected that it will at least last the race (usage life).

Meeting the performance or robustness criteria doesn’t guarantee meeting durability targets. Repeated robustness tests, or “worst-casing”, is no substitute for durability testing.

The following diagram relates the three criteria for a fictitious performance envelope to the modern idea of a 90th percentile usage target:

Performance tests are selected from the boundary of the performance envelope as one-off events. Robustness tests by adding a %age additional ‘overload’ to the maxima or uses an extended envelope & applied a set number of repeats.

Whereas durability load cases derive from 90% of the performance envelope repeated to match the equivalent usage life of the vehicle or system, to failure.

engineers have fooled themselves that information from warranty and in service problems provide realistic tests or load cases that suffice as targets - it is only part of the case.

There was a need to ensure that the usage target and testing developed from its work would be applicable to a larger class or type of vehicle and developed a whole new way of putting the techniques to work.

Current Era (2000 plus)

In recent years development work now focuses on efficiency, economy and green issues. Obviously, without knowing the detailed long term usage of vehicles it is going to be very difficult to predict what the new motive systems, energy schemes, materials, and infrastructure changes will require?

Here at MIRA we are expanding on our revolutionary work at the turn of the century, such that into the 21st Century, we are exploring what happens in the real world and interpreting this into the design, development and testing disciplines. The previous era has, arguably, solved the problem of modelling the real loading conditions for test rigs or CAE modelling. But, as I have discussed, they are in danger of assuming that in enveloping the load magnitudes and frequency contents of the vehicle systems we have all the design information we require. These alone do not produce adequate information for durability and proving work. Finding the actual targets to provide the repetitions of loading and environmental variation necessary to satisfy the required expectations of ‘life’ – more importantly which usage or usages provide the best target.

These goals are almost philosophical in their aims, and it was seen that the majority of the industry treats them as a black art. I maintain that it is possible to map the usage, in a statistically significant manner and to describe a durability target for each of the major vehicle types.

Research work around the World has determined the vehicle target usage for a number of markets and vehicle types. For obvious commercial reasons, and more importantly popular customer demand, MIRA set about determining the automotive usage data and durability information for the emerging markets. This has been systematically carried out firstly in Asia. The first was in China (2000) then extrapolated for Korea and India. Soon, the other areas in the Middle East and other niche markets were investigated. For instance reviewing CarDur to produce the MIRA Low Volume Car Durabiity Schedule, many of these have been presented at a number of EIS events (Figure 2).

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Surprisingly, it was realised recently that no-one had ever truly correlated Europe to provide real durability/development targets. There are, of course, hundreds of empirical testing targets based upon market information and custom & practice, for particular models and makes. It must also be mentioned work carried out by a number of OEM’s who effectively understand their own customers very well, and have determined specific worst case distributions of their users. But, does this knowledge help them understand how all vehicles are used, to break into new markets, use different materials, or develop electric or other alternative fuelled vehicles efficiently. More importantly, do any of the current targets based upon successful sales or customer information, help sell to people who want to put the product to a different usage or is perceived not to cope with their needs.

It is essential to understand how cars in general are used, not necessarily how a particular types of car is used.

Typically European targets quote some large distances on typical roads, typically 200,000 kms. This is not useful to convert to design or durability load cases, as there are too many unanswered questions:

Which roads, for how long and at what mix of loading?

Is the longest distance user the worst, how do I find the worst distance?

What terrain (hills, mountains etc) and at what speeds?

Figure 2: History of correlated durability targets; two of which have been presented at EIS events

What are the seasonal and environmental differences?

… and many more.

I have described in previous EIS papers some of the mathematical techniques used to correlate a known target usage pattern to a proving ground – these are also summarised later. The harder part of the process covers establishing the statistical spread of the usage, not user, patterns of vehicles towards the extremes of the distribution. This involves a huge amount

of resource to ensure that sufficient data is obtained both for how the vehicles are driven, the territory in which they are used, the environmental conditions, and seasonal variations.

One of the more important sets of information required covers total life of the vehicle. How statistics from a number of owners affect the usage pattern, and how to take into account not only the first owner, but the second and even third ownership. It is interesting to note that warranty periods and design targets now span across many years and often more than one owner type.

Figure 3: Real world correlation process

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Latest Durability Target MIRA CARDUR for Europe (2012)

MIRA have a series of vehicle proving ground schedules providing overall design targets for numerous classes of vehicle, termed CarDur (Car Durability) Schedules they provide for the structural or power train usage patterns at typically the 90th percentile usage patterns of drivers. These have been the subject of presentations at EIS events in the past.

We have recently investigated European and UK usage patterns, and carried out a major European survey of medium size car usage. This is the first independent, whole market investigation of its type, and has culminated in a new series of CarDur structural and power train development/durability schedules. The schedules provide realistic 90th percentile usage conditions correlated to general vehicle usage and overall vehicle inputs. The alternative, using the ‘nominal’ or ‘worst case’, conditions will not give optimum design or test load cases.

The target setting starts with a Europe wide market survey to determine the usage of vehicles. The process started by using a professional marketing company to organise a comprehensive market survey for the way medium size cars are driven across ‘Old Europe’; UK, Spain, Germany, Netherlands, Italy, France, Sweden etc.

A series of analysis tools have been developed for both pseudo (explained later) and traditional market surveys. At least two survey tools may be required, one for general drivers (non-professional) where the questions have to be simpler as most normal drivers do not notice road types, conditions etc. and one for professional drivers where a more comprehensive sheet can be used due to the ‘generally’ higher competence level. The latter is more applicable to truck and other professional type vehicles.

These tools are used to calculate or extract, the Stop/Starts and usage info and create look-up tables for each type or class of vehicle (for example inner city, urban or long range business users). So, together with the number of Sales (%age) and the look-up ‘Normaliser’ we can populate the market survey information.

Figure 5: ‘Pseudo survey’ tools – used to setthe survey questionnaire

The market survey company converted these calculation sheets into a series of questionnaires, customised to ensure we obtain adequate information from the market place. They make sure that the questions are asked a number of times and in different ways to elicit realistic answers. Obviously if you ask people how they drive then they all drive carefully, and stick to speed limits and never overload or abuse their car. Questions are developed to elicit the more truthful answers. This has to be done in a number of languages, and sufficient quantity. A questionnaire was created for Europe, in a number of languages and distributed to over 80,000 recipients. The returns were used to provide a statistically significant result, and an enormous set of data covering driving styles, road types, journeys, and other useful parameters.

Figure 4: ‘Old’ Europe data

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The full survey takes many months, and would have created a huge delay in determining the road route and events required for the RLD exercise and subsequent correlation analysis to the proving ground (PG). To reduce the overall time a parallel process was used to provide a first estimate of the 90%’ile.

The new process was termed a ‘pseudo survey’ and uses a form of Weibull extrapolation (a normalised population distribution) to provide an estimate of the usage patterns at the 90%’ile from much simpler information. A “Pseudo survey team”, or teams, consisting of; users (often Fleet operators), service, engineers, marketing and sales people who were used to populate a series of ‘pseudo’ survey tables. This allowed us to discover representative road route and events on which to collect RLD in parallel with the survey, at the risk of requiring a slightly larger RLD exercise. Overall this method produces a much shorter timetable for the whole project. The road route RLD are also used to calculate the parameters, surface weightings, and normalisation information required to adjust the user survey data to provide the more specialised ‘usage information’.

RLD is collected for the whole body inputs, essentially attempting to recreate the free body diagram, for this exercise. Note that it is essential to use the input conditions, not overt system reactions or component strains/stresses. Reproducing overall input allows the method to be applied to similar type vehicles, whereas, specific component or system information, and especially component damage information, renders the result applicable only to specific car, model or type. Obviously RLD was also obtained for MIRA’s Proving Ground to provide data suitable for the correlation of the test schedule applied later (sources). Data was collected over any surface deemed appropriate to enable the correlation of the schedule to the target durability life. Data was collected at the same weight conditions as derived in the survey results used.

The data collected from the public roads are then assembled into one or more of the usage patterns at the 90th percentile condition (targets). This ‘target’ data set is then used alongside the ‘source’ data for the Proving Ground to develop test schedules correlated to real customer usage.

The main central correlation is carried out in the cyclic domain, for input loading conditions. The source and assembled target RLD was converted to cyclic information (typically range-mean histograms or similar) and the whole data set assembled to provide the cyclic histories for the 90th percentile target. Similar classifications are used for the Proving Ground data.

These cyclic data sets are mathematically correlated using a number of regression type techniques to provide a mix of PG surfaces to a best fit to the target using a least squares

type approach. The ‘free body data’ is used to ensure all (note “all”) of the input loading conditions are closely met simultaneously. Correlating inputs enables the results to be applied to similar type vehicles in the future. The test schedule & target then become a vehicle class test, rather than a specific customer or model test.

This method differs fundamentally to other correlation processes typically reproducing maximum loading, RMS loading, frequency content or particular component damage due to uniaxial measurements etc. These methods are limited such that subsequent testing is limited to particular problems solving, or to determine the specific reaction of a design to the test, not to design the test itself.

It would of course be far easier to use just vertical loads alone to perform a correlation. But this would mean that XY and other conditions are under tested and make the target and schedule quite limited. Similarly, correlation by assessing the fatigue of particular components, is not adopted because as described earlier, just reproducing the damage to a component or system, does not imply the same mode of usage. More importantly a local fatigue correlation would not apply to other similar vehicles.

In a similar vein frequency correlation approaches alone can easily miss one-off or random singular events at the population usage extremes due to the inherent averaging of the techniques. Although useful for application in the aerospace, or off shore industries, they are less applicable to long term vehicle testing. Having said this, these functions are also used as part the process, but do not rely exclusively on them.

Figure 6: Medium size car and a ‘Free Body Diagram’

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Following cyclical extrapolation, as mentioned above, the RLD is then also interrogated for frequency content (similarly rotational information for powertrain). A series of related correlation methods are then applied comparing the cyclic results but in the frequency domain. This cross correlation ensures we account for the major whole body inputs and also vibrational conditions during the life of a vehicle.

It is important to note that MIRA now produce durability tests for classes of vehicle, effectively that are becoming a ‘must pass’ type standard. The author has experienced over the years that many OEM’s assume there are individual durability test & proving tests specific to their market or product and aimed at their customers. It can be seen, from our work, that these bespoke tests all contain a central core test that forms a vehicle test standard.

In particular, it includes a large number of PG surface in the exercise not just traditional durability surfaces. This helps us to meet another goal to satisfy ‘how should different OEM’s pass the core test’; to just pass it (cheaper car), to far exceed it (be the strongest), to remain ‘quiet’ (very refined car), and lately, to handle/perform well through life. This we accomplish by replacing portions of the central durability test with specific OEM assessment features that will maintain OEM differentiation in the market, and sensibly account for them whilst reproducing real world conditions.

In addition, the latest work can also provide additional target such as; long distance business/workingtype usage, city centre/urban commuter type usage, and low mileage standard/average commuter or occasional user. All of these would still be considered to be at the 90th percentile ‘usage’ conditions for specific user or system level work. This level of detail allows for braking, steering, emissions, and even translation to hybrid and alternate fuel usage.

Future Applications of Real World Correlation

It is the author’s experience that once electric, hybrid, range extended or similar alternate fuelled vehicles become free of the imposed infrastructure restrictions the usage patterns will become very similar to that of current traditionally fuelled vehicles.

For instance pure electric powered vehicles currently are limited by rate of recharge, spacing of recharge stations, and battery charge capacity on board. In these circumstances the usage pattern can be determined by the limitations and can be correlated separately. Whereas modern hybridised vehicle (such as the Toyota Prius) or the newer range extended EV’s (such as the Vauxhall Ampera/Proton Exora) are not limited, and provide the same overall range of driving

Figure 7: MIRA vehicle monitoring – 30 drivers, 12 channels, 20 Hz sampling, over a year > 1 Terabyte

Figure 8: Car controlled and monitored by the infra-structure on the MIRA - InnoVITS track – Real World RLD


15

as ‘normal’ vehicles, only differing in how the loading is shared amongst the various vehicle systems to achieve the target. All of these can be extrapolated from general usage information now established.

I am sure work will continue into correlation exercises to map the 90th percentile usage pattern even better. As more vehicles are now fitted with feedback control for intelligent transport systems, such that journeys, global position, driving styles and other information will be continuously monitored; we will see a huge amount of data being acquired by manufacturers, government and others on how we are driving en-mass (Figure 7).

Future real world data will arrive from on vehicle transmitters, providing system information continuously. The art will be filtering and interpreting this information. For instance current work on the MIRA based InnoVITS new test facility is already providing feedback on the type and extent of data required for future traffic & vehicle control systems.

Converting all this data into useful information will be one of the biggest challenges. A recent exercise for a number of typical car users (30) and collecting a few basic CANbus pieces of data, accelerometers and typical GPS/speed data at relatively low sample rates, (a few 10’s of samples per second from some 12 inputs) generated a massive amount of data during the months of data collection. Something over a terabyte of data had to be analysed, without sensible automated analysis algorithms, and modern software tools this would have been impossible in the past (Figure 8).

The future for data collectors is going to be interesting, there is a real danger that we, will become very data rich, having access to a plethora of data from each individual vehicle, for every trip, continuously and for a large number of vehicles, but in reality we could become information poor by not being able to apply and use the information.

Conclusion

I hope that this and the previous article has provided an introduction to the history and current work being carried out to try to ensure that vehicle testing is based on the real world, and also accounts for the variability encountered by vehicle users.


Diary of Events

Annual Instrumentation, Analysis & TestingExhibition

The Silverstone Wing, Silverstone Race Track12 March 2013. 10:00-16:00

Further details on page 3.____________

Understanding Vehicle Ride Comfort andSeating Dynamics

Joint Seminar from EIS and Sound & Vibration Product Perception Group and Institute of Sound and Vibration

Research (ISVR)

Human Factors Research UnitISVR University of Southampton

Thursday, 11 April 2013Further details on page 21

_____________

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16

ENGINEERING INTEGRITY, VOLUME 33, NOVEMBER 2012 pp.16-20. ISSN 1365-4101/2012

Abstract

The Tyre Cavity Microphone (TCM) is shown to be capable of providing useful insights into the coupling of tread input forces with the tyre structural and cavity modes when the wheel is running on both test laboratory 2 metre diameter steel road wheel (roller) and on normal road surfaces. The mapping of internal tyre cavity noise levels to the far field radiated noise is demonstrated to an accuracy of 0.5dBA. Internal cabin noise level, at the primary cavity resonance frequency, is shown to be correlated with the phase angle of the primary mode in each tyre. Future research directions are described that will confirm these findings across a broader range of tyres.

Introduction

Tyres have always made a noise and in general the wider the tyre and the bigger the tread blocks the noisier the tyre will be. Legislation introduced across Europe in 20121 reduced the allowable far field radiated noise, for a given size of tyre, by approximately 2dBA. The challenge for tyre manufacturers was to achieve this noise reduction while simultaneously improving both wet grip and rolling resistance. This paper presents a new and novel transducer, the TCM, that was used extensively in the development of quieter tread patterns at Cooper Tire, Melksham UK.

The tyre noise challenge

To reduce tyre noise levels for vehicle occupants and for the wider environment.

If tyre noise is an issue for a customer then it will most likely be based upon the noise that they hear inside the vehicle when driving. The legislation will act only to control the noise radiated outside the vehicle. The vehicle users choice of tyre will be determined by their understanding or experience of what will constitute a quiet tyre. The new tyre labelling system will be of little help in reducing internal vehicle noise levels and so help reduce driver fatigue.

The currently available measurement tools

Tyre noise would ideally be measured on a standard road surface, i.e. one found commonly in the urban environment but alas and perhaps understandably a pragmatic selection was made and the vehicle pass-by surface chosen. The road surface that is being driven over for a tyre noise test is significant to the result by 10dBA and conceivably more. Tyre noise testing therefore got off to a dubious start in-

Technical PaperTyre noise measurement - A new approach (Tyre Cavity Microphone – TCM)Alan Bennetts, Bay Systems Ltd and Neil S. Crookes, Cooper Tire

so-far as legislation designed to minimise tyre noise in the urban environment was prescribed a road surface for testing that never occurs on real roads! Inevitably tyres were developed to pass the noise test defined in ISO 13325 (the actual surface is defined in ISO 10844:2011 Acoustics -- Specification of test tracks for measuring noise emitted by road vehicles and their tyres). The anomaly was recognized and a pragmatic answer has been the further reduction in the target levels for tyre noise.

When testing tyres for noise in the laboratory, in a hemi-anechoic environment, the microphones are positioned close to the contact patch with the tyre running on a large ( >2metre diameter) steel road wheel (roller) with either a smooth or textured surface.

On the test track, for legislation testing, the microphone(s) are positioned at 7.5 metres from the vehicle’s centre line. If testing for R&D the far field microphone is typically augmented by in two or more microphones positioned in and around the wheel arch. For internal vehicle noise measurements microphones are typically located at the driver and passenger ear positions. Vibration levels are monitored with accelerometers positioned on the suspension members and the chassis mounting points. What is missing?

In the laboratory it is difficult and very expensive to measure the forcing function and tyre deflections when running at speed. On the test track the input forcing function and the tyres response are next to impossible to measure. The force input to the tyre is generated by the interaction of the tread pattern and the road texture. As every motorist knows tyre noise changes by noticeably (several dBA) as the vehicle transitions from one road surface to the next. The radiated noise figure, in dBA, that must be recorded for the pass-by noise test can vary by >6dBA depending on which, nominally identically surfaced, ISO track is used for the measurement. At the very least this means that a tyre with a low dBA level on it’s label may in fact be noisier than the tyre next to it on the tyre dealers shelf that may have a higher noise level displayed. For the vehicle’s occupants the only tyre noise level that they can be aware of is the cabin noise generated by the tyres as they drive along. The vehicle users, given the power to choose, will almost certainly select the tyre that reduces to a minimum the noise reaching them. However the internal cabin noise will not necessarily correlate with the pass-by noise level noise figure so prominently displayed on the tyre label. As already

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discussed this dBA level may not offer a true comparison due to ISO10844:2011 surface differences and the fact that tyre noise transmission into the vehicle need not match the radiated noise efficiency. Does this mean that the customer has been deceived if the new tyre proves to be noisier than expected on the local roads? The vehicle manufacturers need tyres that give them a noise margin that will help achieve the whole vehicle pass-by noise target level. The ISO 10844:2011 test track that the vehicle manufacturer uses is unlikely to be the one that the tyre manufacturer used and so there will be room for a difference of opinion as to what the noise contribution from the tyres actually is. Additionally vehicle manufacturers need the lowest possible road noise levels inside the vehicles cabin to enhance customer satisfaction. After all why would the customer buy a car that was noisy on their local roads when another car seems to run more quietly? So while more information for our customers is better and can allow an informed choice we do now seem to be running the risk of confusing and annoying our customers when the tyre does not do what it says on the label! A question worth asking is whether there is a better way to characterise tyre noise and whether there might be a better way of measuring it. Is the sound pressure level (SPL) inside the tyre cavity an answer?

The input at the contact patch is transmitted through the casing to the air inside the tyre. Some of what happens at the road tyre interface (contact patch) is therefore transmitted to the air in the tyre where it is amplified by standing wave resonances in the tyre cavity and structural resonances in both the tyre and wheel. One or more Tyre Cavity Microphones (TCMs) may sit in the cavity and measure the changing sound field, see figures 1 & 2. Figure 1. shows a TCM mounted in the wheel well of a normal road going alloy wheel of typical modern car size 17 inch diameter and 7.5 inch width. Not shown is the power module which to all intents and purposes is of identical size and weight and is diametrically opposite the microphone module. It is known that tyres from different companies may have different characteristics: - rolling resistance, handling, wet grip and noise to name but four of a possible twenty plus parameters that characterize a tyre. Data taken in the laboratory for a number of coast down runs, from 100kph to 30kph, show almost perfect repeatability. The data shown in figure 2 is from two coast down runs, the data was taken 10 minutes apart and demonstrates that the behaviour of the sound field inside the tyre’s cavity is repeatable.

Good repeatability on the road, where the surface is irregular would seem more unlikely. However the TCM responses from the average of four tyre time histories, see

figure 3, for north and south going runs at 77kph were in very good agreement. Translating this time data to the frequency domain and separating the data into cavity mode dominated, low pass filtered, and the tread dominated frequencies regimes, high pass filtered, see figure 4 & 5, where the overall Awt levels are plotted against time. The cavity dominated, lower frequency regime (<800Hz), exhibits

Figure 1. TCM on 17 wheel 007_2

Figure 2. TCM data from two runs of 4 x 4 tyre 100 to 30 kph

Vertical scale increments 10 Pa. Time axis scale increments 0.1 seconds

Figure 3. Time average of 4 tyres’ TCM

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good < 1dBA differences at the centre of the run however there are differences towards the beginning and end of the run of up to 4dBA. Although further work needs to be done to confirm the increased discrepancy at start and finish it is suspected that there was some interaction with the power train due to the test vehicle not permitting a true free wheel. At higher frequencies (>800Hz) where the signal content is dominated by tread and road surface noise, the comparison of the north and south going runs again shows an agreement to within <0.5dBA at the centre and <2dBA at the beginning and end of the runs. The frequency content of the cavity microphone data for the two 77kph runs, north going and south going, shows near identical levels for the first and second cavity modes, see figure 6. Above the major cavity mode (>800Hz) the frequency content of the two 77kph runs is within 0.6dBA, see figure 7.

A critical test that must be passed before tyre cavity noise

data can be used to guide tyre noise development is that it reliably reflects actual changes made to the tyre. One way to test this sensitivity is to compare the level changes associated with changing speed. This can be achieved by comparing the ISO coast-by noise results with the cavity noise results over a range of speeds. The experimental set up for this measurement was as for the normal ISO standard coast-by noise test with the exception that a TCM was fitted inside each tyre. On the outside of the vehicle, a midsize SUV in this case, a small magnetically attached antenna was placed on the body near each wheel. Inside the vehicle the 4 cables from the antenna were connected to a recording system. As the vehicle began each run the recording was started; at the end of the run the recording was stopped. The excess recording, approximately 10 seconds in duration, before and after the critical 20 metre long ISO section, was of interest as it showed how each tyre’s cavity modes were excited through the acceleration phases. The data for

Runs @77kph N = red S = blue plotted against time from 13.8 to 15.3 secondsFigure 4. TCM lower frequencies Awt overall Figure 5. TCM higher frequencies overall Awt

Figure 6. Cavity mode resonances Figure 7. TCM High Frequency @ 77kph

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speeds from 72-90kph is presented in Table 1. Unfortunately, as is often the case, two data points are missing due to high background noise at the ISO coast-by microphone. The data in Table 1 demonstrates that the Internal TCM level does indeed follow the far field radiated noise trend that is measured at the ISO defined far field microphone position. The TCM level is therefore responding, as does the PBN level, to increasing speed and in the case of a tyre, increasing speed results in increasing force input at the contact patch. The noise level measured inside the tyre is unaffected by background noise and therefore allows testing to be carried out on days where the wind is too strong for an ISO test. Additionally once the correction factor from ISO 10844:2011 surface to a local road surface is established it is possible to obtain ISO PBN levels by driving on the local road. This will save test time enabling faster and more economical tyre development cycles while offering the additional benefit of easy data acquisition for running over non ISO surfaces; giving the potential for tyre manufacturers to develop tyres that perform well on both ISO and regular road surfaces.

The spectral content within the tyre cavity, for a progression in pass-by speeds from 74kph to 91kph, shows a relatively uniform increase in each third octave band with increasing speed, see figure 8.

Noise Inside the Vehicle

Vehicles propelled by electric motor(s) will have no combustion noise to mask road and tyre noise. Should the trend towards lighter structures and deteriorating road surfaces continue then road and tyre noise will become ever more apparent to the people in the vehicle. Reduction in road and tyre noise, particularly for urban motorway speeds < 80kph, is likely to become a focus for both tyre and vehicle manufacturers over the next ten years.

In vehicle noise (cabin) levels associated with tyres will be made up of two principal components:

1. The primary tyre cavity mode and possibly other resonance effects of tyre and wheel2. The tread noise exciting response in the vehicle structure and airborne transmission The TCM data can be successfully correlated with microphones positioned within the cabin to reveal when and

how tyre noise enters the cabin. Initial research indicates that the phase of the primary cavity resonance within each of the four tyres has an important bearing on the level measured in the cabin.

The recording of two microphones at the drivers and/or passenger’s head position while also gathering the TCM data from each wheel requires an expansion from 4 to 6+ channels; allowance should be made for an engine tacho to allow power train related noise to be screened out of the analysis. For the time history shown the driver needed to make some adjustment to the speed to hit the target speed of 86kph at the entry gate for the ISO coast-by test run. The time at the entry gate was 4.2 seconds and the time leaving the gate was 6 seconds at which point the driver again changed speed. These adjustments to brake and or throttle are significant because they put additional energy into the tyres. The overlay of the summed and high pass filtered data

Table 1. Comparison of averaged TCM levels and PBN levels for normal road and ISO surface

S p e e d

kph

Averaged road

TCM in dBA

Predicted PBN

for road dBA

PBN for road

in dBA

Predicted PBN

for ISO in dBA

PBN ISO

surface dBA

72 114.1 73.8 76.7 71.4 71.374 114.0 73.7 No data 71.3 71.176 114.1 73.8 75.2 71.4 72.077 115.2 74.9 76.0 72.5 71.980 114.7 74.4 74.4 72.0 72.082 115.7 75.4 75.6 73.0 73.084 117.3 77.0 75.5 74.6 73.786 116.8 76.5 76.7 74.8 74.888 117.6 77.3 77.6 74.9 74.690 117.2 76.9 77.8 74.1 No data

Figure 8. TCM spectral content vs speed

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(100Hz to get rid of the power train noise) is shown in figure 9. The summed TCM data shows a very strong series of resonant peaks just before the entry between 3.6 and 4.2 seconds and again at 7.5 & 8.5 seconds.

The time domain data exhibits a strong visual correlation between the summed tyre waveform and the summed ear waveform. The implication from this analysis is that when the SUV’s 4 tyre’s primary cavity mode is simultaneously generated and in phase then the primary cavity resonance appears strongly in the cabin. This should therefore show up strongly in the frequency domain where a strong modulation of the 177Hz primary cavity tone should appear in the cabin when it goes high at all four tyres. The results of a joint time frequency analysis, otherwise known as Wavelet analysis, does indeed reveal just such a correlation see figure 10a & b. Inside the tyre cavity, figure 10a; the 177Hz primary cavity mode is low through the run but much higher after the run is complete. This is reflected almost perfectly inside the vehicle cabin, see figure 10b. In addition to the cavity mode the cabin data also shows the power train line rising dipping at 2 seconds and 105Hz.

Conclusions

There is strong correlation between the sound pressure levels (SPLs) measured inside the tyre cavity and both the radiate far field noise and the tyre noise heard in the vehicle. Using data gathered by a TCM should enable faster and more economic data collection for both tyre and vehicle manufacturers. The tyre manufacturer should be able to optimise tread pattern design so as to avoid exciting a strong cavity resonance. Vehicle makers may use TCM to help in route tracking road noise transmission paths. The TCM technology will allow vehicle manufacturers to set target noise levels for tyre manufacturers to meet when tyres are running on a smooth laboratory steel wheel as these results will map to ISO surface and internal vehicle noise levels.

Regulators may wish to consider defining tyre noise limits based upon internal tyre SPLs for either steel wheel or a variety of road surface types and so remove a degree of uncertainty from the current ISO measurement standard.

References

1. Tyre noise legislation 2012 for all new tyres effective 1st November 2012 regulation 661/2009 and explained in the tyre labelling directive 1222/2009.

The authors wish to thank Cooper Tire for the use of facilities and permission to publish this work.

(If you would like to receive a colour copy of this paper please email: [email protected])

Figure 9. Times tcm & ear

Figure 10a. Wav tcm

Figure 10b. Wav response at driver’s ear

Call for PapersJoint Seminar from Engineering Integrity Society (EIS)

Sound & Vibration Product Perception Group and Institute of Sound and Vibration Research (ISVR)

‘Understanding Vehicle Ride Comfort and Seating Dynamics’ Venue: Human Factors Research Unit, ISVR, University of SouthamptonDate: Thursday 11th April 2013

6-axis motion simulator of the Human Factors Research Unit

To optimise the vehicle ride comfort, account must be taken of many factors, including design of vehicle seats, occupant characteristics, posture and activities, and seat dynamic properties. The dynamic response must be ‘tuned’ to minimise relevant adverse effects on comfort, health, or performance.

This one-day event at the Human Factors Research Unit (HFRU) will involve:

• informal presentations

• panel discussions

• a tour of the HFRU’s wide range of human-rated test facilities

• simulator demonstrations including the HFRU unique 6-axis motion simulator

• exhibitions

• posters

The event provides an opportunity for those involved in the fields of vibration, transport or seating to present their research or applications and to meet with those from industry and academia working to improve the performance of seats for road, rail, sea and air transport. We are pleased to acknowledge the support and co-sponsorship of the IMechE.

Applicants are invited to submit an abstract of their presentation, consistent with the theme described above. Closing date for abstract submission is Friday 7 Dec 2012.

Please contact:

Sara Atkin, Engineering Integrity Society,17 Harrier Close, Cottesmore, Rutland, LE15 7BTTel: 01572 811315Email: [email protected] www.e-i-s.org.uk/

http://www.soton.ac.uk/HFRU

22

In engineering terms when a component or structure vibrates at its own natural frequency it can be considered to be in a state of resonance. Any vibration in a component or structure has the potential to cause damage and even failure, however, when the vibration occurs at the resonant frequency the amplitude of the vibration can become very large for a relatively small input of force. This is obviously very dangerous in a safety critical component, assembly or structure and engineers have to ensure through their design, modelling and testing that this situation will not occur in service.

The phenomenon of resonance however can be advantageous when applied to engineering testing because it allows very large numbers of fatigue cycles to be applied with a relatively low power input when compared to other forms of testing such as servo-hydraulic systems.

In order to test at resonance it is necessary to create a single degree of freedom arrangement, this can be achieved either in a fairly conventional load frame Figure 1, or by special adaption of the component itself to produce a tuning fork effect Figure 2, as decribed in detail in the following article. In both systems the forcing input is provided by an electrical device commonly know as a shaker. This is basically an electro-magnetic device which oscilates a central armature at a controlled frequency Figure 3.

The control system for vibration testing is closed loop comprising a power amplifier which drives the shaker with a sine wave and a servo controller which compares the response signal from a transducer which can be load, displacement

How it Works - Testing Using the Concept of Vibration and Resonance

Key

1 Main Mass 2 Central Table Mass 3 Test Sample 4 Load Cell 5 Shaker 6 Preload Springs 7 Vertical Load Frame Columns 8 Bearings 9 Adjustable Cross-head 10 Ball Screw 11 Ball Screw Drive 12 Anti Vibration FeetFigure 1 – Typical Resonance Test Load Frame

Figure 3 - Central Pivoted Shaker

or acceleration. In a resonance test, the controller sweeps through a frequency range until the test piece is at its natural frequency, at this point the power input requirement drops to a minimum and the controller locks on to this frequency. When the component starts to fail, its stiffness changes resulting in a shift in its natural frequency, which can be detected by the servo controller and used to stop the test and record the number of cycles to failure. This is described in more detail in the following article which gives an example of resonance testing of crankshafts.

In addition to durability tests, vibration can also be used to provide model validation by using small force exciters to create resonance in a component whilst measuring deflection and strain distributions. This same data could be used to define actual test levels for component life tests for comparison with computer life predictions.

Graham HemmingsEIS Simulation, Test &

Measurement Group

Figure 2 – Tuning Fork Type Test System

Test Piece

Shaker

Tuning Fork Weights

Control Accelerometer

23

The main reciprocating components of an internal combustion engine, such as pistons, connecting rods, gears and crankshafts are subject to very high cycle loading, resonance testing offers a low power, efficient and cost effective method for testing these and other automotive components such as engine mounts, exhaust systems, driveshafts, as well as those from aircraft and civil engineering. Resonance is simply the enhanced vibration of an object subjected to an oscillating force close to a natural frequency of the object.

In the case of the crankshaft, the loading comprises a combination of bending and torsion. In order to evaluate the fatigue performance of a crankshaft it is sensible to separate these loads. To further simplify the test and to evaluate the performance in a critical location, the crankshaft can be cut into individual throws.

Testing can be performed using a servo hydraulic machine, however, this usually limits the loading to compression only and also the test frequency is relatively low when taking into consideration a mid range engine speed 4500rpm which equates to 75Hz.

An alternative test method is to use a resonance system to excite the component. This is achieved by mounting the crankshaft throw in a “tuning fork” arrangement suspended from a gantry by rubber cords and then exciting it with an electro-dynamic shaker via a stinger rod.

The critical location on the component is at the stress concentration in the fillet radius.

In order to determine actual test stress levels, a strain gauge is fitted in this location and then once the system is running at resonance, the amplitude is set to achieve the desired strain response from the gauge.

If an accelerometer is fitted to one of the “tuning fork” legs, then the acceleration level may be correlated to strain and plotted as a calibration curve. Once the test is running,

then providing the system remains in a stable condition, i.e. the journal clamping and suspension remains secure, then the assembly will continue at resonance until the component starts to fail. When this happens, the resonant frequency will change because the overall system stiffness will alter due to the growth of a radial crack in the fillet radius. The controller can be set to shut the test down when the frequency changes by a certain level e.g. 3Hz.

Advantages of this test method

• Electro-dynamic shakers have relatively low force capability when compared to hydraulic machines. The “tuning fork” resonant test method enables these shakers to generate the high forces and loading frequencies experienced by the crankshaft in service.

• The ability to test at high frequencies reduces test time and allows the engineer to test more components within a short period, which is useful if conducting quality control tests for production. Also, if development tests are required to compare design, material or heat treatments, then again more samples can be compared within a short time frame.

• The overall test system is relatively cheap to purchase, and maintain compared to hydraulic systems. Also, it is fairly straight forward to operate therefore training and operational costs are lower.

Disadvantages of this test method

The “tuning fork” resonant test method can only apply sinusoidal loads therefore it is not possible to simulate the true loading regime of the crankshaft which comprises higher loading due to engine firing loads than the inertial load when the piston is moving upwards.

The actual tuning fork assembly has to be designed to match the particular crankshaft application in order to enable resonance to be achieved and at the same time

Resonate to Accelerate

24

Resonate to Accelerate ...... continuedproducing the correct bending moment in the critical location.

The initial test set up is critical, any out of alignment or loosening of clamping loads on the journals will prevent resonance to be achieved and maintained. Because of the masses and suspension systems involved, this is not the easiest of processes. The “stinger rod” connecting the shaker to the “tuning fork” is necked down to a small diameter at both ends to allow a degree of flexibility. This produces a location of weakness which will easily fail if the rod encounters off balance forces. A stock of these components will be required.

Graham Hemmings

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16th International Conference on Experimental Mechanics - First Announcement7-11 July 2014 Cambridge

● The 16th in a series of conferences, starting in Delft in 1959, this is the premier event to showcase novel and innovative research in Experimental Mechanics. ● The conference brings together internationally leading researchers across a wide range of disciplines in both academia and industry to interchange ideas and discuss new research.● An interactive exhibition of state of the art instrumentation will take place at the conference.● See the brightest early career researchers take part in the Young Stress Analyst Competition which is sponsored by industry.● Celebrate the 50th Anniversary of the journal Strain, the British Society for Strain Measurement and the 100th Anniversary of the Spilt Hopkinson Pressure Bar.● Enjoy the sights of Cambridge, the reception at the Fitzwilliam Museum and the banquet under the wings of Concorde at the world famous Imperial War Museum, Duxford.● The conference is organised by the British Society for Strain Measurement on behalf of the European Society for Experimental Mechanics and chaired by Professors Janice Dulieu-Barton and Fabrice Pierron from the University of Southampton and Professor Chris Truman from the University of Bristol.

The BSSM and EURASEM welcome you to Cambridge and invite you to visit the conference web site for further details:

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25

inlet charge pressure after the turbo. In some operating situations it is now necessary to throttle the inlet air to force a positive pressure gradient for EGR.

A number of strategies can deliver this. Vehicles with variable geometry turbochargers (VGTs), whose vanes can be physically moved, can to some degree heat up the exhaust and adjust the pressure within the EGR system. In combination with an exhaust throttle or exhaust brake, this set-up can deliver the level of performance required to meet Euro VI. However, fuel consumption is often increased when an exhaust throttle is used.

Another alternative – but one only likely to be effective on vehicles covering long-haul routes – is to operate SCR at the very highest conversion level, which can achieve the emissions standard without EGR. However, this will significantly increase urea usage and still requires exhaust temperature management when operating at low loads or during cold starting.

What is ideally needed, therefore, is a system which can manage the flow of inlet air into the system, assist EGR and manage exhaust temperatures with minimal impact on fuel consumption. This can be achieved using an air inlet throttle. Some system designers have sought to ‘upscale’ air inlet throttle technologies originally developed for passenger cars typically from petrol engines. While these systems have been approved by some less

demanding vehicle manufacturers, independent tests have raised significant question marks over their ability to meet the more severe operating conditions required of heavy duty engine applications.

Initially pneumatic actuation was considered for these throttles. However, the lack of speed and precision, and high air consumption associated with pneumatic actuation, meant this approach was dropped in favour of electric actuation. Furthermore, pneumatic components are frequently subject to ‘overshoot’ - moving past the required operating angle and then correcting themselves – rather than offering the precise movements needed to cope with specific operating requirements. Given the move in general towards electrical components in engines, such as for turbochargers, and the recent availability of high performance brushless motors, electric inlet throttles have become the standard.

The latest innovations in this area are ‘smart’, meaning they have local control and condition monitoring and communicate with the vehicle network via CAN. They use a proven DC brushless motor directly coupled to a throttle

Innovating in inlets – new technologies to meet emissions legislation for heavy diesel enginesMark Sealy, Engineering Director - Commercial Vehicle Sector, Norgren

Diesel emissions legislation has become ever more stringent, with increasingly harsh penalties for operators of non-compliant vehicles. Aiming to minimise particulates and nitrous oxides (NOx), the new Euro VI standard comes into force in Europe at the end of 2013, while EPA13 demands similar standards in the US. For trucks and buses, Euro VI sets a maximum of 1.5g/kWh of soot and 0.4g/kWh of NOx.

NOx emissions levels are five times lower than those stipulated in the current Euro V standard, placing greater demands on engine and after-treatment system designers to incorporate technologies to minimise emissions.

Currently, there are three main ways of achieving this. Exhaust Gas Recirculation (EGR) systems reduce the available oxygen, the temperature of combustion and therefore the NOx generated.

Selective Catalytic Reduction (SCR) involves introducing urea into the exhaust system, where it reacts with exhaust gases in combination with catalysts to minimise NOx presence.

Finally, a soot filter traps particulates and burns them off using an integrated flame generation system. Both the SCR and soot filter systems are located at the end of the exhaust pipe directly before exhaust gases leave the tail pipe.

To meet the new Euro VI standard, it is common practice to employ all three of these technologies. However, to incorporate all of them into a modern diesel engine and have them operating at optimum efficiency creates a further requirement – to precisely control the air flow rate into the engine and exhaust treatment systems.

This is because SCR systems, and the catalysts within them, must be maintained at a high temperature - typically at least 200ºC – to operate effectively. Periodically exhaust temperatures need to be above around 300°C to establish a flame to burn the trapped soot, a process called active regeneration. This is a particular issue in vehicles operating in urban areas or ‘multi-drop’ routes, where system temperatures typically remain cooler than on inter-city drive cycles. In these instances, pollutants are not always converted into harmless by-products sufficiently, or the filters cannot regenerate, meaning the vehicle becomes non-compliant and the vehicle control system must then limit the engine to ‘de-rated power’. It is therefore imperative to raise exhaust temperatures, as required, with minimal additional fuel consumption.

Meanwhile, for EGR systems to operate optimally, exhaust pressures before the turbo must be maintained above the

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body and air control flap designed specifically for commercial vehicle applications. Receiving cooled air from the charge air cooler, the inlet throttle ensures air is precisely metered into the engine and exhaust treatment system, delivering benefits in several key performance areas.

The first is maintaining high exhaust temperatures, to ensure optimum temperature of SCR catalyst, and to initiate filter regeneration with minimal additional fuel consumption.

Secondly, the inlet throttle optimises the pressure gradient driving EGR, allowing the best “in-cylinder” combustion conditions under various operating modes.

Thirdly, it can be used in conjunction with other controls to optimise soot combustion during filter regeneration.

Fourthly, it can assist in the cold start of emissions components, reducing the oxygen available to them, similar to a petrol engine choke.

Finally, the inlet throttle can force immediate shutdown on key off, eliminating the ‘run-on’ commonly found in modern high-compression engines.

To deliver these benefits, the inlet throttle must meet several key design parameters. Perhaps most important is speed, with an operation time as short as 100ms desirable. Secondly, it must be ‘high-resolution’, delivering precise flap positioning to tolerances of 1/4°, or less. The product must also be superdurable and able to withstand 10 million cycles or more. Sealing capacity is also key, so the engine can be shut off immediately on demand. Just as important, however, the inlet throttle must never shut off the engine unintentionally, meaning it must automatically return to the open position under its own spring force in any potential failure mode. These performance parameters require a compact and durable motor with a very high power density.

Numerous other key features are achievable in this system type based on its ability to perform its own condition monitoring and then automatically take corrective action. A common risk of throttling inlet air in adverse climatic conditions is the potential to form ice. If such conditions are detected, the valve can be agitated rapidly to shake off ice accumulation while in cases of ice build-up, it has a ‘hammer’ function to break off any ice formed in the throttle. In extreme cases the valve can switch itself off and attempt to reactivate at regular intervals.

An optional ‘wake-up’ function can also be integrated, enabling the valve to start operation before the engine is switched on, and operate after the engine is switched off.

Leading systems of this kind incorporate steel gears for enhanced durability as opposed to plastic, while special FKM Viton seals, stainless steel valve elements and special housing coatings are used to resist the corrosion caused by the development of acidic condensates from exhaust residues. An operating range of between -40°C and +140°C is achievable, requiring sophisticated greases able to withstand these temperature extremes. Meanwhile, further design innovations have ensured these systems fit compactly into different engine spaces.

These operating capabilities can of course only be guaranteed following highly stringent testing. Modern vibration tests, for example, involve subjecting valves in various orientations to many hours of highly amplified accelerations while operating and also being subjected to temperature variations.

Vibration and its impact on physical performance and service life has driven some key design advances. Opposed angular contact ball bearings eliminate free ‘play’ in bearings and so better combat vibration effects by preventing fretting and knocking. However, the latest bearing systems also incorporate o-rings in their cases to stabilise them further, also ensuring a very consistent meshing distance between the gears.

Meanwhile, each component must not be affected by critical natural frequencies. Thermal cycling and shock testing to assess product performance under sudden changes in temperature - plunging the unit alternately into ice and then boiling water is the usual format - are also key in determining the point at which units leak or crack, or seals start to fail. Pressure leak testing – to both positive and vacuum pressures – provide a guide to performance under different operating conditions, while modern corrosion tests involve subjection to a range of acids to determine effect on seal performance and unit integrity.

However, perhaps the greatest challenge is in ensuring performance repeatability between individual valves. The flap placement in the tube is critical here as this governs sealing quality and leakage potential. Manufacturers are constantly reviewing how to optimise repeatability but key to this is the end of line torque signature.

Inlet throttle technology is already making its first appearance in ‘incentive engines’ being fitted into vehicles to be purchased by ‘early adopters’ of the Euro VI standard.

Find out more at www.norgren.com/uk/commercialvehicle.

Innovating in inlets – new technologies to meet emissions legislation for heavy diesel engines . . . . cont.

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Industry newsWelcome to the Industry News section of the journal. Thank you to everyone for their submissions. The nominal limit for entry is 200 words, which should be sent to [email protected] or posted to EIS, c/o Amber Instruments Ltd, Dunston House, Dunston Road, Chesterfield, S41 9QD. We would appreciate you not sending entries by fax.

Paul Armstrong

New figures report revival for engineering and building graduates

Despite a weakening economy and the continuing struggle in construction, the employment rate for new building and engineering graduates has improved and unemployment has dropped, according to research published today (11 October 2012) by the Higher Education Careers Services Unit (HECSU).

HECSU’s What Do Graduates Do? reports the destinations of 14,295 first degree building and engineering graduates in January 2012 (six months after they left university), which makes up 5.8% of the overall 2011 graduate cohort.

The figures show revival in engineering, which has experienced poor employment outcomes since the start of the recession. Employment rates for architecture and building (65.9%), civil engineering (62.8%), electrical and electronic engineering (63.9%) and mechanical engineering (65.6%) were higher than the average of all graduates from first degree disciplines (61.8%).

Career prospects had also improved since the previous year with 65.8% of employed mechanical engineering graduates (59.4% in 2011), 36.2% of electrical and electronic graduates (30.9% in 2011) and almost three in five civil engineering graduates (54.6% in 2011) all working as engineering professionals in January 2012 (six months after graduating).

The unemployment rate has dropped across all subjects with the exception of electrical and electronic engineering graduates – 8.4% architecture and building (9.5% in 2011), 9.5% civil engineering (11.4% in 2011), 8.9% mechanical engineering (9.3% in 2011) and 12.1% electrical and electronic engineering (11.2% in 2011).

The average salaries for full-time first degree building and engineering graduates entering full-time employment in the UK increased compared to the previous year, except civil engineering which saw the average salary decrease slightly to £22,720. Average salaries: £17,950 (architecture graduates), £24,825 (mechanical engineering graduates), £20,585 (building graduates) and £22,880 (electrical and electronic engineering).

What Do Graduates Do? is published in collaboration with the Association of Graduate Careers Advisory Services. The report can be downloaded at www.hecsu.ac.uk

European Rail Research Centre

On 10 October Hitachi announced the creation of a European Rail Research Centre in London that will look at rolling stock design, manufacturing practices, maintenance and traffic systems.

The company is supplying the next generation of Intercity trains to the UK under the Intercity Express Programme and has recently received an order to supply a Traffic Management System to Network Rail.

Shigeru Azuhata, Executive Vice President and Executive Officer, Hitachi Group Chief Technology Officer, commented: “At Hitachi, we place huge importance on research and development, as demonstrated by our extensive laboratories around the world. With the growth of our rail business in Europe and the UK, we felt that it was paramount to establish a dedicated research facility directly

where key issues in areas such as maintenance, manufacture and Traffic Management Systems will present themselves.

Search for an icon: Queen Elizabeth Prize for Engineering launches £5,000 trophy prize

On 9 October The Queen Elizabeth Prize for Engineering launched a competition in association with the Tate, the Design Museum and the Science Museum, for young people in the UK to design the iconic trophy that will be presented to the winner of the prestigious £1 million international prize.

16 to 24 year olds are being invited to submit a design that represents the wonder of modern engineering. Anyone in that age group can enter, with particular interest expected from those studying or working in art, design, fashion and technology, as well as those studying or working in engineering. The winning entry will reflect the creativity, power and importance of engineering so that the trophy is a symbol of the integral role the engineering profession plays in society.

Finalists will see their designs prototyped using state-of-the-art 3D printing. Every finalist will be invited to London to present their prototyped design in person to the panel of judges. The winning design will be used to create the trophy for the inaugural Queen Elizabeth Prize for Engineering and the winning designer will also receive £5,000.

Using the latest programming and design technology a unique digital application has been developed for the trophy competition. Entrants will create and ‘build’ their designs in a 3D online environment. The application can be downloaded free from the Queen Elizabeth Prize website and must be used by everyone entering the competition.

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Student puts engineering career into ‘pole position’, thanks to MIA scheme

As part of a unique scheme, organised by the Motorsport Industry Association (MIA), David Cullimore, together with five other students undertaking STEM subjects (science, technology, engineering and maths), have been specially chosen to meet and learn from the UK’s best high performance engineering businesses.

David is 18 years old and aims to go to university to study engineering. As one of the MIA’s ‘Motorsport STEM Ambassadors’ for 2012, he spent several days in September with Drayson Racing Technologies, the Oxfordshire-based company developing the world’s fastest electric racing car.

A student at St Edwards School in Cheltenham, David said: “Becoming an MIA Motorsport STEM Ambassador is a huge achievement for me, considering the competition. This opportunity gave me the chance to talk to experienced engineers, which will, I know, really help my future engineering career.”

Chris Aylett, chief executive of the MIA, said: “Our ‘Motorsport STEM Ambassadors’ scheme helps to pick out the bright stars of tomorrow, giving them the chance to shine in front of UK businesses which could soon be their employers. We want to inspire young people to follow their dreams and become one of our nation’s world-beating engineers of the future”.

To find out more about the MIA’s Motorsport STEM Ambassadors programme, please go to www.the-mia.com

Bloodhound SSC presents ‘golden opportunity’ to encourage next generation of engineers

On 2 October the President of the Institution of Mechanical Engineers said that the Bloodhound Supersonic Car project is a great way to encourage

young people to consider a career in engineering. Professor Isobel Pollock said “The Bloodhound project is much more than a world record attempt. It is a golden opportunity to show the younger generation how exciting an engineering career can be.”

“The UK faces an engineering skills shortage that threatens to derail many sectors of the economy. Presenting young people with such a perfect example of the ingenuity, skill and drive that defines British engineering is a great way to encourage more people into the profession.”

The comments were made in advance of the first test of the hybrid rocket which took place at Newquay airport on Wednesday 3 October. This was the biggest rocket fired in Britain for over 20 years.

The Institution of Mechanical Engineers is an education partner of Bloodhound SSC. It has over 150 specially trained Bloodhound ambassadors working with schools across the country to help inspire schoolchildren to consider a career in engineering.

University to develop ‘super batteries’ with E.ON

The University of Nottingham is working with E.ON to develop a next generation ‘super battery’ which will enable households and businesses to benefit from clean, cheap and powerful energy storage. The contract with the University to develop the new energy storage device (known as a supercapattery) is one of three research projects amounting to a total of £1 million that E.ON is sponsoring, which aim to improve energy storage technologies and energy efficiencies for businesses and households.

The largest of the three projects that the University is undertaking with E.ON is the development of the supercapattery technology. A supercapattery

combines the power of qualities of a supercapacitor with the energy storage benefits of a battery, and does so at a low price. Made from carbon nanotubes chemically engineered with advanced battery materials, the supercapattery has a variety of applications ranging from powering portable electronics such as notebook computers, to using arrays of supercapatteries which would offer large scale energy storage solutions for power companies.

Supercapatteries can also be brought into action at very short notice to provide the additional power required, and the crucial stability needed by the national grid, in the event of a national power surge.

University opens new Institute for Advanced Manufacturing

On 19 September David Willetts, Minister for Universities and Science, opened a new Institute for Advanced Manufacturing at The University of Nottingham.

The aim of the Institute, which has received £2 million from the University’s Capital Investment Fund, is to centralise activity and drive the development of cutting-edge technology in one of the University’s key research areas. It encompasses an international team of established academics in their respective fields in the UK and also at its campuses in Malaysia and China.

The Engineering and Physical Sciences Research Council (EPSRC) has provided £550k for the Institute to invest in specialist equipment. In addition, the European Regional Development Fund (ERDF) is providing a further £979k to support business engagement and knowledge transfer activities with local SMEs with the aim of supporting innovation and growth within the region.

The University of Nottingham’s research portfolio presents a unique, integrated and holistic approach to

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manufacturing, focusing on themes including process technologies, composite manufacturing, food and additive manufacturing, digital manufacturing and operations management.

The Institute has partners in sectors as diverse as aerospace, automotive, medical, instrumentation, defence, power engineering, textiles and clothing. Major global stakeholders include Airbus, Rolls-Royce and BAE Systems, all with strategic and operational links to the Manufacturing Technology Centre in Coventry.

For more information about The University of Nottingham’s services for business, visit www.nottingham.ac.uk/servicesforbusiness

Leading Chinese aerospace business to fund University Innovation Centre in Nottingham

The University of Nottingham is developing a new University Innovation Centre (UIC) with one of China’s biggest aerospace businesses. Under the agreement with ACAE (AVIC Commercial Aircraft Engine Company Limited) the University, will, over the next three years, undertake a number of civil aerospace research projects in the UIC. These include investigating impact damage on composite materials, as well as research into thermal barrier coatings to help improve the performance of engine components such as turbine blades, which have to operate in very high temperatures.

The University Innovation Centre being developed with ACAE is worth over £1 million per annum to the University, and follows on from a framework agreement which was signed with ACAE and their parent company, AVIC, earlier this year. AVIC is one of the giants in the Asian aerospace industry, employing over 400,000 people in China and owning assets valued at £29 billion. The company is already sponsoring a group of around 20 of its

own employees, who are undertaking postgraduate and masters studies at The University of Nottingham. The University of Nottingham is also building a new Aerospace Technology Centre, to strengthen links with global aerospace firms and increase the amount of industrial research undertaken by the University in the sector. The Centre aims to consolidate The University of Nottingham’s position as an internationally leading institution for aerospace research. For more information about The University of Nottingham’s services for business and the work of the Asia Business Centre, visit www.nottingham.ac.uk/servicesforbusiness Shale gas exploitation will help rebalance economy, say engineers

Shale gas is ‘no silver bullet’ for UK energy security but will provide long-term economic benefits

The exploitation of UK shale gas resources has the potential to create thousands of high-skilled engineering jobs over the next decade, one of the UK’s largest engineering institutions said on 18 September.

The Institution of Mechanical Engineers, in a policy statement circulated to parliamentarians, notes that 4,200 jobs per year would be created over a ten-year drill programme, with 1,300 created annually in Lancashire alone. The engineering skills developed could then be sold abroad, just as the oil and gas experience built up in North Sea oilfields is now being sold across the world.

The Institution also warned that the development of shale gas must be coupled with the development of Carbon Capture and Storage (CCS) technology for use with gas-fired power plants. The statement recommends that low-carbon gas generation is included in the forthcoming Electricity Market Reform bill.

Dr Tim Fox, Head of Energy and Environment at the Institution of Mechanical Engineers and lead author of the Shale Gas policy statement, said “UK shale gas could make a helpful contribution to the UK’s energy security for the next two centuries, but it is not the silver bullet many claim it is. It is unlikely to have a major impact on energy prices and the possibility that the UK might ever achieve self-sufficiency in gas is remote”.

Second astute class submarine sets sail on sea trials

Barrow-in-Furness, UK. On 15 September the second Astute class submarine Ambush set sail from BAE Systems to begin sea trials with the UK Royal Navy.

The 7,400 tonne attack submarine left the site in Barrow-in-Furness, Cumbria for Her Majesty’s Naval Base (HMNB) Clyde, Faslane, which will become its operational base. This major milestone in the submarine programme is the point at which Ambush will begin to test its range of capabilities, under the control of Ambush Commanding Officer, Commander Peter Green and his crew.

Ambush is the second in a planned class of seven submarines and she follows sister vessel HMS Astute to HMNB Clyde, in Scotland, where the first in class has been based since leaving BAE Systems in 2009.

The Astute class boasts a range of world class capabilities inside each 97 metre long hull. Powered by a Rolls-Royce nuclear propulsion system, the reactor never needs refuelling. The sonar system has the processing power of 2,000 laptops and can track ships 3,000 miles away. They are armed with both Tomahawk land attack missiles and Spearfish torpedoes and her missiles have a target range of 1,200 miles with accuracy measured in metres.

HMS Astute is currently on sea trials

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and in March this year successfully test fired four Tomahawks, and six Spearfish torpedoes, including the first salvo by a British submarine for 15 years, during trials in America.

UK engineers believe Government is failing the industry

• Over half of UK engineers have lost confidence in government policy on engineering

• Over half of UK engineers are not confident that companies will continue to invest locally

• Two in five respondents said it is very possible they will work abroad in the next five years

A new Confidence Index from Matchtech, the number one engineering recruitment company in the UK, has revealed that over half (53%) of UK engineers have lost confidence in government policy towards the industry. The Confidence Index, which surveyed more than 1,000 engineers in the UK, indicates a strong sense of unease in the industry; not only have engineers lost confidence in the Government, over half (56%) fear that organisations will stop investing locally, and two in five (43%) would be willing to desert the UK and move abroad for work.

Engineering has, for many years, been the backbone of the UK economy. The Index examined confidence levels on a selection of engineering career and industry related issues. Now, nearly three quarters (74%) of UK engineers do not believe enough is being done by the Government to encourage innovation in the UK, and over two thirds (67%) do not feel confident that the UK will be a world leader in engineering in the future.

Keith Lewis, managing director of Matchtech, commented: “It is evident that there are a number of critical issues here that need to be addressed to remove the sense of trepidation within the industry. The Index shows this needs to start with the Government,

but there is a lot to be done in a short space of time. Perceptions need to change fast, and the Government needs to reassess its priorities urgently to prevent a further shift of attitude that could come with hugely detrimental consequences. With Business Secretary, Vince Cable’s, recently announced strategy for industrial policy in Britain, the one thing the Government is doing well is projecting a time for change in the industry. But the Confidence Index statistics suggest it could be too little too late.”

Other significant findings include:

• More than three quarters (78%) do not believe enough is being done by the Government to attract new blood into the industry

• Nearly half (46%) of UK engineers are less confident they will have a job for life compared to when they first started in engineering

Lewis continued: “These statistics reveal further problems with the engineering industry. A complete shift in attitude not only means reinstating confidence, but ensuring that the industry continues to evolve. It simply cannot do this if both the current generation and the next generation of engineers are not on board. Without this, all the evidence suggests that it will not be long before the UK is robbed of its mantle as world leader of engineering.”

The Annual Knovel University Challenge

On September 10, 2012 Knovel, the leading provider of a Web-based application integrating technical information with analytical and search tools, kicked off the Knovel University Challenge with a new twist: additional prizes will be awarded on a weekly basis, giving students 12 more opportunities to win.

The Annual Knovel University Challenge, now in its seventh year, continues to grow in popularity among

engineering students globally. Faculty increasingly use it as a tool to introduce future engineers to top-notch resources available in the library as students learn how to research, problem-solve and prepare for a competitive workforce. Engineers at more than 300 companies worldwide incorporate Knovel into their workflow, so the University Challenge helps students to jumpstart their use of a resource that will be relevant throughout their careers.

More than 400 of the world’s top universities provide access to Knovel. Current engineering and science students from any of these universities can learn more, register and participate at www.knove lun ivers i tycha l lenge.com. Participation spans the globe and many professors incorporate the challenge into their curriculum.

The Knovel University Challenge presents a series of questions on engineering-related topics, and students are encouraged to use Knovel and related features to find the correct answers. Prizes are awarded weekly to students of top-participating universities and at the conclusion of the contest.

NAFEMS World Congress 2013, 9-12 June 2013 Salzburg, Austria

This will be the only independent, global conference that focuses entirely on simulation and its impact on industry and beyond.

This landmark conference addresses the breakthrough technology of SDM and will help participants better understand the benefits gained from implementing a Simulation Data Management system and how to save time, reduce development costs, and improve time-to-market.

Attendees from around the globe will take part in the event, from every industry involved in engineering simulation and analysis and SPDM.

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Expected presentations:

• Examples and best practices in industry

• Requirements and use cases• Solutions from software vendors• Strategies, developments, trends

and future of SPDM

Visit www.nafems.org/congress to view full details.

6th Chaotic Modeling and Simulation International Conference, (CHAOS2013), Yeditepe University, Istanbul Turkey, 11-14 June 2013

First call for Abstracts/Papers

The general topics and the special sessions proposed for the Conference include but are not limited to: Chaos and Nonlinear Dynamics, Stochastic Chaos, Chemical Chaos, Data Analysis and Chaos, Hydrodynamics, Turbulence and Plasmas, Optics and Chaos, Chaotic Oscillations and Circuits, Chaos in Climate Dynamics, Geophysical Flows, Biology and Chaos, Neurophysiology and Chaos, Hamiltonian Systems, Chaos in Astronomy and Astrophysics, Chaos and Solitons, Micro- and Nano- Electro-Mechanical Systems, Neural Networks and Chaos, Ecology and Economy. The publications of the conference include:

1. The Book of Abstracts in Electronic and in Paper form.

2. Electronic Proceedings in CD and in the web in a permanent website.

3. Publication in the Journal of “Chaotic Modeling and Simulation”. Please see and download the Papers of 2011 and 2012 Issues at: http://www.cmsim.eu/journal_issues.html

For more information and Abstract/Paper submission and Special Session Proposals please visit the conference website at: http://www.cmsim.org or send email to the Conference Secretariat at: [email protected]

9th International Conference on Advances in Experimental Mechanics, 3-5 September 2013 Cardiff School of Engineering, University of Cardiff

The British Society for Strain Measurement’s (BSSM) 9th International Conference on Advances in Experimental Mechanics will offer industry and academia the opportunity to discuss advances in experimental mechanics.

Set against one of the most vibrant and beautiful cities in the world, the conference will combine the modern facilities of the Cardiff School of Engineering with the traditional surroundings of the Viriamu Jones Gallery and one of Europe’s finest art collections at the National Museum Cardiff, where the conference dinner will be served.

Key dates:

• Online Extended (2 page) Abstract Submission:15 January – 18 March 2013

• Extended Abstract Submission: 18 March 2013.

• Decisions on Submitted Extended Abstracts: 15 April 2013.

• Reviews of Extended Abstracts to Authors: 26 April 2013.

• Final Extended Abstract Submission: 31 May 2013.

• Early Bird Registration Deadline: 31 May 2013.

• Submission: 31May 2013.

For further details please visit: www.bssm.org/conf2013

16th International Conference on Experimental Mechanics (Icem 16) 7-11 July 2014 Cambridge

First Announcement

The 16th in a series of conferences, starting in Delft in 1959, this is the premier event to showcase novel and innovative research in Experimental Mechanics.

The conference brings together internationally leading researchers across a wide range of disciplines in both academia and industry to interchange ideas and discuss new research.

An interactive exhibition of state of the art instrumentation will take place at the conference.

See the brightest early career researchers take part in the Young Stress Analyst Competition which is sponsored by industry.

Celebrate the 50th Anniversary of the journal Strain, the British Society for Strain Measurement and the 100th Anniversary of the Spilt Hopkinson Pressure Bar.

Enjoy the sights of Cambridge, the reception at the Fitzwilliam museum and the banquet under the wings of Concorde at the world famous Duxford air museum.

The conference is organised by the British Society for Strain Measurement on behalf of the European Society for Experimental Mechanics and Chaired by Professors Janice Dulieu-Barton and Fabrice Pierron from the University of Southampton and Professor Chris Truman from the University of Bristol.

The BSSM and EURASEM welcome you to Cambridge and invite you to visit the conference web site for further details: www.icem16.org

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Product newsNew modular Instron® CEAST Melt Flow Testers perform measurements according to ISO 1133-2

High Wycombe/UK, October, 2012 – The new, modular Instron® CEAST MF20 and MF30 Melt Flow Testers are versatile single-weight measurement systems suitable for use both in research and development and in advanced quality control. They provide the user with increased convenience for easy and accurate measurement of the flow properties of plastics according to ASTM D1238 and ISO 1133. Both lines of melt flow testers conform to strict tolerances with regard to temperature accuracy and stability, specimen quantity and pre-treatment, complying with the stringent requirements of the new testing standard ISO 1133-2 for materials sensitive to time-temperature history and/or moisture.

The CEAST MF30 includes a weight magazine and weight lifter (available as an option for MF20). The weight magazine contains a complete set of 8 test masses ranging from 0.325 kg (piston mass) up to 21.6 kg for testing a wide spectrum of materials, from fast-flowing masterbatches to highly viscous elastomers or filled thermoplastic polymers. A high-convenience mechanical system, the newly developed Manual Mass Selector, enables pre-selection of the required test mass, thus facilitating preparation and execution of the tests. All test masses remain installed on the machine at all times. This eliminates the need to handle and apply heavy test masses and significantly enhances the safety of the laboratory staff.

Measurement Computing (Norton, MA), the value leader in data acquisition, has announced the release of USB DAQ device support for Android-based tablets

As tablets gain popularity, Measurement Computing is at the

forefront of targeting these new devices with its low-cost USB data acquisition products.

The Android OS is supported through DAQFlex, a simple and efficient message-based programming interface. The DAQFlex for Android API and example programs are included with select MCC DAQ devices.

The Android API provides programmers with a method of communicating with these devices without the need for understanding USB communication mechanisms.

Unlike most DAQ devices, which interface to the computer via low-level commands, DAQFlex devices interface with simple text messages. In addition to Android, DAQFlex also includes out of the box support for Windows®, Linux® and Mac®.

A whitepaper on using Android with MCC DAQ hardware is available for download from the Adept Scientific website www.adeptscience.co.uk

SKF bearings extend bakery maintenance intervals tenfold

SKF high temperature bearings have enabled Evron Foods to extend maintenance intervals in their ovens from three months to almost three years – and counting. The upgrade is one of the many application-specific solutions provided every day by SKF, the knowledge engineering company, that cut costs and maximise plant performance in applications across industry.

Evron Foods specialises in the manufacture of bakery products for retail, wholesale and beyond, both on behalf of private labels and under its own Easibake brand. The company operates from two sites, one based in Northern Ireland and the other in Wales.

At both of these sites, transfer

units move trays of product through the ovens to carry out the baking process. These transfer units run on rollers inside the ovens and four rollers are required for each support station along the way. As there are five support stations in each oven, and therefore 20 rollers, each oven requires 40 bearings.

The first bearings were installed at the Northern Ireland site in May 2009 and proved to be an instant success, easily exceeding the three-month maintenance interval demanded by the previous bearings. Naturally enough, subsequent orders were then made for Brammer to provide SKF high temperature bearings for Evron’s Welsh site.

At the time of writing, the bearings originally installed in Northern Ireland during May 2009 are still in operation, having effected a 1000% improvement on the previous bearings.

For further information, please contact: Phil Burge, Communication Manager, SKF (U.K.) LimitedTel: +44 (0)1582 496433 Mobile: +44 (0)7770 647591 [email protected]

New Safety Device has the Vision to Help Protect

The Allen-Bradley® GuardMaster® SC300 is a Type 3, vision-based protective device designed for use in a variety of machine-guarding applications

14th September 2012 - The latest addition to the Rockwell Automation safety opto-electronic product family, the SC300 Hand Detection safety sensor is a compact Type 3, SIL 2, IEC 62061, PLd EN ISO 13849-1 Vision-Based Protective Device (VBPD), which uses image-processing technology to detect the intrusion of objects through its detection window.

The safety-sensing function is performed by a single image sensing

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diesel engine manufacturers face ever tighter exhaust emission regulations, which could adversely impact engine performance and especially fuel consumption without the right technical solution,” says Nick Pascoe chief executive CPT. “We now have the means of producing the cleanest engines ever by delivering very quickly and precisely the mass of air necessary for optimum combustion, particularly during transient events, which helps avoid the need for expensive exhaust after-treatment. Electric supercharging is a new and exciting and as yet unexploited technology that will help to reduce fuel consumption and emissions, and thereby the cost of vehicle ownership. Cobra deploys robust and reliable switched reluctance motor technology and is easily packaged with the engine.”

Model of a modern measurement meter

Fourth generation sound analysis hardware from Brüel & Kjær

Sound and vibration specialist, Brüel & Kjær has launched a fourth generation of hardware for its sound level meters and hand-held analyzers - Types 2250 and 2270 G4.

This new hardware enables Types 2250 and 2270 users to run multiple, upgraded applications, such as frequency analysis, logging and signal recording. It also has a high-contrast colour screen, which makes performing outdoor measurements easier for environmental officers and consultants.

The Type 2270 G4 meter provides users with dual-channel capabilities, such as sound intensity for noise source location measurements in vehicles, sound power for testing consumer goods or machinery during development and building acoustics tools, which can be used for measuring sound insulation inside structures. The new hardware

has boosted the meters’ processing capabilities for faster calculations and increased battery life.

All Type 2250 and 2270 instruments running version 4 of the instrument software can interface directly with Vaisala ultrasonic weather stations, which allows seamless integration of noise and weather data within the sound level meter, so wind affected noise measurements are easily identified.

GPS devices (Global Positioning Satellite) can also automatically record the measurement location, making it simpler to link noise levels to particular areas during the post-processing stage.

More information on Type 2250 & 2270 G4 is available at: http://www.bksv.com/doc/bp2025.pdf

Oil-free lubricant from Millers Oils improves tube bending efficiency

Water-based gel eliminates the need for degreasing while improving tool life

Yorkshire, UK – Millers Oils has developed a completely oil-free product that improves manufacturing efficiency by eliminating the need to degrease manipulated tubes before welding. Called Solform 135, the water-based gel replaces conventional oil- and soap-based tube bending.

Conventional products contain chlorinated paraffins that lead to corrosion of steel tubes after welding due to hydrochloric acid formation with moisture from the air. The standard solution to the problem has been to include a degreasing stage in the production process. Solform 135 Gel eliminates the issue entirely because it’s water-based so the tubes can be welded straight away after bending.

Ideal for assemblies, such as exhaust

device, which views a single two-dimensional image against a passive pattern as the background. The detection principle is based on an object of a certain resolution blocking the image-sensing device’s view of the pattern.

Targeted at light and medium industrial machine guarding applications, the GuardMaster SC300 can be used for frame openings ranging from 400 x 400mm up to 1500 x 1500mm.

The SC300 is incredibly versatile and is easy to install and set up, providing a cost effective, 20ms response, hand-detection solution that can replace 24–30mm safety light curtains. Its small size and detection offset allows it to be mounted on the inside or outside corner of a frame opening, maintaining the opening while helping protect the SC300.

The unit is used in conjunction with special reflective tape, which defines the boundaries of the sensing field.

Launch of CPT Cobra electric supercharger offers low cost solution for meeting Tier 4/5 emission regulations without compromising fuel economy

Technology developer, Controlled Power Technologies (CPT) has launched what is believed to be the world’s first water cooled electric supercharger developed for ‘quasi continuous’ boosting of commercial diesel engines including those developed for off highway applications. Known as Cobra, the market ready technology was debuted at the world’s leading automotive engineering conference focused on air boosting technologies, which was held in September in Dresden. The Cobra electric supercharger is particularly relevant to Tier 4 Interim legislation that comes into effect this year for off road vehicles.

“The availability of this new air boosting technology is timely as

34

systems, Solform 135 Gel can be used as supplied and is easily applied via the mandrel lubrication system, or hand applied direct to the mandrel. The gel formulation thickens under temperature, meaning less product is required while improving tool life and reducing scrap, to generate significant process cost savings.

The formulation is non-drip, providing a clean working environment, and was developed using Millers Oils’ expertise from high temperature chain lubricants.

“Our independence as a lubricant producer and our extensive in-house R+D facilities allow us to develop optimized solutions to the specific problems of particular industries,” said Mann. “Solform 135 Gel is a great example of this.”

Dormer expands threading programme with Chrome Taps

Dormer Tools has added to its threading programme with the launch of a new range of taps.

Designed to promote a continuous production process in structural grade steels, carbon steels, copper and brass, the new taps feature a Hard Chrome Plating (Cr).

This treatment has the benefit of significantly increasing surface hardness – up to 68HRc - but also prevents swarf from sticking to the tool. Combined with geometry design to provide optimum flute space, the feature promotes negligible chip congestion and increased productivity.

A short thread length generates low torque, meaning the new taps can be run at higher operating conditions with no detrimental effect on tool life or workpiece surface finish.

Fabio Sala, Dormer product manager, said: “Dormer has traditionally been associated more with the

development of innovative drilling products, a key area which continues to the present day. However, our portfolio of threading products has developed in tandem with our drilling programme over recent decades.

Available in Metric or Metric Fine thread forms with spiral point or spiral flute geometries, all taps are manufactured from premium grade high speed cobalt to provide optimum edge strength and wear resistance.

For more information about Dormer’s Chrome Taps visit www.dormertools.com

The New Revolution Scanning Vibrometer PSV-500 from Polytec

Polytec’s new revolutionary scanning vibrometer is being introduced, tailored to the four main application fields of more than 1,000 users: acoustics, structural dynamics, experimental modal analysis and ultrasonic’s.

The quality of both the vibration and geometry data is significantly improved by optimizing all elements of the measurement chain.

The most important achievement was the introduction of “VibroLink”, with fully digitized processing of measurement data. Data from the vibrometer and up to 8 data acquisition reference channels, for driving point and excitation force for example, are commonly transferred via Ethernet to the processing unit, avoiding any unnecessary sources of noise.

Better core performance: At the heart of each laser vibrometer is a high precision optical interferometer. The size of this component was reduced by 80%, which helps to reduce the overall size of the scanning head. Secondly, improvements to the mechanics and a lower thermal sensitivity resulted in an increased overall stability of the system.

New low-noise scanners have extended the scan field by 25 %.

With a new HD camera, not only does this provide pin-sharp images of the object under test, but it also creates improved lifelike animations of the results.

This adaptive laser frequency stabilization technology helps to provide optimal optical return signals for all stand-off distances as well as highly reliable measurements on small devices such as ultrasonic motors or tools.

More info: http://www.polytec-ltd.co.uk/uk/products/vibration-sensors/scanning-vibrometers/

Email: [email protected]

Product news

35

Welcome to our usual review of main events and products happening in the field of smart materials and structures. Energy harvesters have been a major source of interest in recent years, and a

significant contribution towards their everyday use has been provided by a team of researchers from the Universities of Cranfield, Liverpool and Salford (http://iopscience.iop.org/0964-1726/21/7/075023). The device, which is strapped to a knee joint, consists of an outer ring and central hub. The outer ring rotates with the movement of the knee, and connects with 72 plectra plucking four energy-generating arms connected to the inner hub. The plectra are bimorph piezoelectric actuators, converting mechanical energy into electric ones and generating up 2 mW within the current design, although further improvement could lead to 30 mW of power generated (making it therefore interesting for GPS systems, for example). The device is clearly targeted to power wearable gadgets, but more could be spun-off from the design.

Energy harvesters are classically based on resonating structures. A team from Tsinghua University (China) has instead developed a novel concept of energy harvester based on sloshing liquids (polyvinylidene fluoride electrets), with their flow producing a variable capacitance significantly efficient especially at low frequencies (http://jim.sagepub.com/content/early/2012/09/09/1045389X12459590.abstract). Best performances for these smart liquids consist on peak output voltages of 11.5 V and power of 2.10 mW at 1 Hz.

Another interesting work on energy harvesting concepts comes this

time from the other side of the pond. A team of researchers from Texas A&M and Northern Arizona University have evaluated the energy harvesting capability of a particular type of magnetic shape memory alloy (MSMA) based on Nickel Manganese Gallium (NiMnGa) (http://iopscience.iop.org/0964-1726/21/9/094018). The microstructure of NiMnGa is constituted by randomly distributed tetragonal martensite variants. When a specific magnetic field is applied, the variants are re-ordered along the direction of the external field. When we add a compressive mechanical stress in direction perpendicular to the magnetic field, the martensitic variants tend to rotate along the stress, and therefore the internal magnetisation vector changes - in other words, the whole magnetisation of the material is modified. This has important consequences on the sensing/energy harvesting capability of the solid. Large orientation strains up to 6.1 % can be used, with a magnetic bias of 0.65 Tesla. The work is at an initial stage, but it is a promising start to evaluate a wider selection of materials for energy harvesting, other than the classical piezoelectric ones.

Continuing on the shape memory alloy side (but not energy harvesting), here in Bristol we have teamed with the European Space Agency Research Centre in Noordwjik (NL) to develop a prototype of deployable reflector based on auxetic architecture, shape memory alloys and PEEK thermoplatic composite (http://iopscience.iop.org/0964-1726/21/7/075013). The antenna prototype has been designed for deep space missions, has a large deployment ratio (> 8), but could also be used for earth-bound operations and general deployable applications. Always in the field of auxetics (this time negative stiffness for high damping), a team from the University of Wisconsin-Madison has developed a concept of

vibration damper based on negative stiffness and large hysteresis PMMA elements, reaching loss factors close to 1 and effective stiffness-damping product of 1.3 GPa exceeding the value of 0.6 GPa offered by damping layer devices. More information can be found at the link: http://iopscience.iop.org/0964-1726/21/7/075026. I would like to end this contribution with mentioning a recent work in the field of smart acoustics. A team from research centres and universities from Taiwan has developed a flexible electret-based cell array loudspeaker (http://jim.sagepub.com/content/early/2012/06/17/1045389X12451192.abstract).

Electret loudspeakers are lightweight, thin, with excellent mid-high frequency dynamics, and have shown remarkable capabilities to be used for specific directivity applications. The design of the smart electret loudspeaker is based on period arrays of actuators, and in this way one can obtain beam patterns with complex and custom-made directivities. An application worth considering for various test cases.

Now a list of some incoming workshops or conferences in the field of smart materials and systems. The ECCOMAS Smart Materials Conference 2013 will be held in Turin (Italy), between the 24th and the 26th of June 2013. The SPIE Smart Materials and NDE Conference will be held (business as usual) in San Diego between the 10th and 14th of March 2013. A range of end-user applications focused on NDE and based on smart materials and systems will be also discussed in DAMAS 2013 in Dublin (Trinity College) between the 8-10 July.

I wish you all a productive and successful months to come.

Fabrizio ScarpaProfessor of Smart Materials and

Structures, Bristol University

News on Smart Materials and Structures

36

News from British Standards – BS 8887BSI has recently published BS 8887-211, Design for Manufacture, A s s e m b l y , D i s a s s e m b l y and End-of-life processing (MADE) – Part 211, Specification

for Reworking and Remarketing of computing hardware and office automation products. It was prepared by Subcommittee TDW/4/7 (BS 8887 Design for MADE), under the authority of Technical Committee TDW/4, Technical Product Realization.

Past purchasers of other parts of the BS 8887 series would be interested in this new standard: BS 8887-1:2006 (General concepts, processes and requirements), BS 8887-2:2009 (Terms and definitions), BS 8887-220:2010 (The process of Remanufacture – Specification), and BS 8887-240:2011 (Reconditioning).

The BS 8887 series is aimed at design engineers, product designers, industrial designers, and engineering designers. BS 8887-211:2012 is the latest standard in the BS 8887 Design for MADE series. It is the first sector-specific part of the series and covers the ICT sector (computing hardware and office automation products).

Part 211 has been created in order to provide the ICT sector with the vocabulary and procedures for its remarketed products. This is necessary as the industry sells a variety of used and remarketed products under a number of different grades and rework procedures. This specific part of the 8887 series is aimed at ICT sector remarketers, for those involved in selling used, repaired, refurbished, remanufactured, or upgraded ICT equipment. This enables the user to understand the processes undertaken by the seller and the level of product quality. Part 211 is applicable to the reworking and remarketing of hardware and, where relevant, the operating

system software and firmware, but does not apply to application software or personal productivity tools.

A remarketed product is a term in the ICT sector referring to a product that cannot be sold as new, even when sold through the Original Equipment Manufacturer’s (OEM) primary or standard channels to market. Some OEMs have specialist or dedicated channels or service providers to market their remarketed products. Remarketed product is also offered for sale by independent refurbishers, but the scope of Part 211 does not apply to product sold direct to a new user by the original or current user, with no reworking, or assurances or warranty offered. Within the ICT sector, the terms Remarket and Resale are treated as synonymous.

Part 211 categorizes the flows of ICT product back into the rework and remarketing process, from assessment and testing to the level of rework required to bring a product back for resale and a second or subsequent productive lifecycle. This includes the element of system or component upgrades which could apply to any of the rework categories.

BS 8887 is developed within BSI’s TDW/4/7 technical committee which covers the new suite of Design for Manufacture standards. BSI welcomes approaches from anyone interested in taking part in standards work and although it requires commitment and contribution, there are various direct benefits that can be gained from participating, such as:

• greater knowledge of and familiarity with existing standards, which can then support evolutionary business ventures, decrease development time, and increase speed to market;

• being proactive and taking a leadership role in proposing the business case for adapting existing standards to suit new products and technologies, or drafting new

standards;

• taking advantage of professional and personal networking opportunities with experts from associated business or technology areas;

• being able to identify and contribute to new areas of standards work and have early access to leading edge knowledge in emerging or developing markets.

Further general information on taking part in standards work can be found at :

h t t p : / / w w w. b s i g r o u p . c o m / e n /Standards-and-Publications/About-standards/What-are-the-benefits-of-standards/

Anyone interested in getting involved in standardization work in the BS 8887 area, please contact Sarah Kelly, Committee Manager for TDW/4/7, at BSI [email protected].

Mark DanisHead of Fujitsu Remarketing

37

For over two years, the Institution of Mechanical Engineers has been working to raise awareness of the potential of air capture technology, which works by absorbing carbon dioxide (CO2), the largest contributor to global warming, from the air. Once captured, the CO2 can then be recycled in industrial processes or be safely stored underground.

Why air capture technologies matter

In recent years, governments across the world have become increasingly aware of the technical, social and economic difficulties in meeting the emissions targets required to avoid dangerous climate change, and struggled to develop effective mitigation policies to address the issue. Air capture technologies could be revolutionary in dealing with difficult to manage emissions like those produced as a bi-product of aviation and dispersed industries with no access to carbon capture and storage (CCS) infrastructure.

Last year the Institution published a position statement calling on more Government support for these emerging technologies and hosted a live demonstration by Professor Klaus Lackner from the Earth Institute in Colombia University showing exactly how CO2 can be captured from the air.

Fuels from air

Now, just a year after showcasing how one version of this technology works, another air capture technology application has been grabbing the headlines in the UK and abroad. On 16 October the Institution held a landmark conference on air capture technology

featuring the world’s leading specialists. During the conference, the small British firm, Air Fuel Synthesis (AFS) based in Stockton on Tees, presented its project which captures CO2 from the atmosphere and then uses it to create synthetic fuels. This process means that CO2 is effectively recycled avoiding further transport emissions.

This recycling works as when fuel is used in a car, this leads to carbon being emitted into the atmosphere. If this carbon is collected from the air, turned back into fuel and put back in the car, the whole cycle begins again. The combination of air capture with synthetic fuel production provides a way to stop putting ‘new’ carbon emissions into the atmosphere from the transport vehicle, effectively stabilising emissions from that source. One of the significant advantages of this approach is the potential economic savings as a result of not having to completely replace the world’s liquid hydrocarbon infrastructure to accommodate a different energy system, such as one based on batteries for example.

This recycling approach can be used with transport vehicles that are particularly problematic to tackle, like aircraft. The high energy density of aviation fuel relative to its volume, weight and ease of use means that this sector is likely to be one of the longest to persist in the use of liquid hydrocarbons, despite advances in batteries and other alternative energy sources.

The idea of producing synthetic transport fuels has been with us for a long time, dating back to before the Second World War and continuing through to practical application in South Africa under the anti-apartheid sanctions. The concept of using atmospheric CO2 to provide one of the chemical feedstocks has only been under consideration for the past few decades, driven largely by increasing concerns about climate change. AFS are the first company to build a small

pilot plant and try it. Their process works as follows:

• Air is blown into a tower containing a mist of sodium hydroxide which reacts with the carbon dioxide in the air, forming sodium carbonate. Electricity is then passed through the sodium carbonate to release the carbon dioxide, which is stored.

• Water is split into hydrogen and oxygen using electrolysis.

• The carbon dioxide and hydrogen are reacted together to create Syngas, which is then processed to form methanol.

• The methanol is passed through a gasoline fuel reactor, creating fuels to specification.

As it was designed purely to demonstrate the feasibility of the process, the AFS pilot plant is currently inefficient in that much more energy is fed into the plant than is extracted back out. It is anticipated that by the time a well engineered demonstration plant has been built for small commercial scale production the balance for the AFS synthetic fuel process will be around 3 units ‘in’ for 1 ‘out’. Part of the solution to this energy imbalance is to drive the process with renewable energy that would not otherwise be used and is not able to be stored. This becomes even more attractive in countries or regions where there is an abundance of renewable energy potential, such as sun in desert regions, but no use for it because urban centers are too far away or population density is too low. These sources of energy can be used to drive the fuel making process which could give these regions fuel supply security and even a potential export product. AFS recently created its first litres of fuel at the company’s demonstrator plant and says it is now ready to build its first commercial production plant making carbon-neutral fuels.

By Dr Tim FoxHead of Energy and Environment at

the Institution of Mechanical Engineers

News from the Institution of Mechanical Engineers

38

Group NewsSimulation, Test & Measurement GroupFollowing the resignation of Conway Young from the STMG Chair, I have agreed to

cover this role whilst we recruit a new Chairman. My first duty therefore is to thank Conway on behalf of the EIS and the STMG for his input over the last two years.

Following the success of the 2012 event and the positive feedback received from both exhibitors and visitors we have again booked the International Media Centre at Silverstone Race Track for the 30th Instrumentation Analysis

and Testing Exhibition. The facilities within the new Silverstone Wing are excellent, with the exhibition hall, forum rooms and the cafeteria all adjacent to one another, making accessibility to all of these very convenient for the visitors and exhibitors. The exhibition continues to grow in size and attracted 48 exhibitors this year compared with 40 exhibitors at the 2011 exhibition. The number of visitors held up well under the current economic climate, and was similar to those who visited the 2011 exhibition. A number of open forums were held in parallel sessions, the first time this format had been used at the exhibition, and these events proved to be very popular with the visitors. For the 2013 exhibition we plan to run a minimum of four forums during the day covering subjects such as residual strain effects and considerations, electric actuators, KERS and finally

improvements in whole testing and predictive processes. This event will take place on 12th March 2013, so if you intend to visit please pre register by emailing [email protected].

The STMG have identified a number of events that we intend to run over the next 12 months. These include:-

A Hydraulic Systems training course to be held at Star Hydraulics at Tewkesbury focusing on servo valves and basics including oil cleanliness, rules, reservoirs, hoses and piping etc.

An event on short fibre composites.

These are currently in the planning stage and further information will be published on the EIS website when available.

Richard HobsonChairman

MEMBERSHIP

The Engineering Integrity Society is an independent charitable organisation, supported and sponsored by industry. The Society is committed to promoting events and publications, providing a forum for experienced engineers and new graduates to discuss current issues and new technologies. We aim for both company and personal development and to inspire newly qualified engineers to develop their chosen profession.

Events run provide an ideal opportunity for engineers to meet others who operate in similar fields of activity over coffee and lunch. All of our events enable engineers to establish and renew an excellent ‘contact’ base while keeping up to date with new technology and developments in their field of interest.

We are involved in a wide range of Industrial sectors including Automotive, Aerospace, Civil, Petrochemical etc and continue to be interested in new members from all sectors.

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If your membership has expired or you are unsure if your membership is current, contact: [email protected]

39

President: Peter Watson O.B.E.Acting ChairmanTrevor Margereson, Engineering Consultant ................................................................................................... 07881 802410Vice ChairmanRobert Cawte, HBM United Kingdom .............................................................................................................. 0121 733 1837TreasurerKhaled Owais, TRaC Global ............................................................................................................................. 01926 478614Company SecretaryRobert Cawte, HBM United Kingdom .............................................................................................................. 0121 733 1837EIS Secretariat

Communications Sub Committee – ‘Engineering Integrity’ Journal of the EISHonorary EditorKaren Perkins, Swansea University ................................................................................................................ 01792 513029Managing EditorCatherine Pinder .............................................................................................................................................. 07979 270998

Durability & Fatigue GroupChairmanRobert Cawte, HBM United Kingdom .............................................................................................................. 0121 733 1837SecretaryKhaled Owais, TRaC Global ............................................................................................................................. 01926 478614MembersJohn Atkinson, Sheffield Hallam University ......................................................................................................0114 2252014Martin Bache, Swansea University .................................................................................................................. 01792 295287Peter Blackmore, Jaguar Land Rover .............................................................................................................. 01926 646757Feargal Brennan, Cranfield University ............................................................................................................. 01234 758249Amirebrahim Chahardehi, Cranfield University ................................................................................................ 01234 754631John Draper, Safe Technology .........................................................................................................................0114 255 5919Karl Johnson, Zwick Roell Group ..................................................................................................................... 0777957 8913Davood Sarchamy, British Aerospace Airbus .....................................................................................................0117 936 861Giora Shatil, Darwind.................................................................................................................................+31 (0)30 6623987James Trainor, TRW Conekt Engineering Services ....................................................................................... 0121 627 4244John Yates, University of Sheffield ...................................................................................................................0114 222 7748

Sound & Vibration Product Perception GroupActing ChairmanJohn Wilkinson, Millbrook Proving Ground ...................................................................................................... 01525 842526MembersMarco Ajovalasit, Brunel University ................................................................................................................. 01895 267 134Joe Armstrong, Polytec .....................................................................................................................................01582 711670Alan Bennetts, Bay Systems ............................................................................................................................ 01458 860393Dave Boast, D B Engineering Solutions .......................................................................................................... 01225 743592Mark Burnett, MIRA ......................................................................................................................................... 02476 355329Gary Dunne, Jaguar Land Rover ..................................................................................................................... 02476 206573David Fish, JoTech .......................................................................................................................................... 01827 830606Henrietta Howarth, Southampton University ......................................................................................... 023 8059 4963/2277Paul Jennings, Warwick University .................................................................................................................. 02476 523646

Committee Members

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Richard Johnson, Sound & Vibration Technology ........................................................................................... 01525 408502 Chris Knowles, JCB ........................................................................................................................................ 01889 59 3900Jon Richards, Honda UK ................................................................................................................................. 01793 417238Ian Strath, LMS International ........................................................................................................................... 02476 408120Keith Vickers, Bruel & Kjaer UK ..............................................................................................................................................

Simulation, Test & Measurement GroupActing ChairmanRichard Hobson, Serco Technical & Assurance Services ................................................................................ 01332 263534MembersPaul Armstrong, Amber Instruments ................................................................................................................. 01246 260250Ian Bell, National Instruments .......................................................................................................................... 01635 572409Steve Coe, Data Physics (UK) ......................................................................................................................... 01323 846464Colin Dodds, Dodds & Associates .................................................................................................................... 07880 554590Dave Ensor, MIRA ............................................................................................................................................ 02476 355295Graham Hemmings, Engineering Consultant .................................................................................................. 0121 520 3838Trevor Margereson, Engineering Consultant .................................................................................................... 07881 802410Ray Pountney, Engineering Consultant ............................................................................................................ 01245 320751Tim Powell, Bruel & Kjaer VTS ......................................................................................................................... 01763 255780Gordon Reid, Engineering Consultant .............................................................................................................. 01634 230400Nick Richardson, Servotest .............................................................................................................................. 01784 274428 Paul Roberts, HBM United Kingdom ............................................................................................................... 0785 2945988Jarek Rosinski, Transmission Dynamics .......................................................................................................... 0191 5800058Geoff Rowlands, MIRA .................................................................................................................................... 02476 355517 Frank Sherratt, Engineering Consultant ........................................................................................................... 01788 832059Bernard Steeples, Engineering Consultant ...................................................................................................... 01621 828312Norman Thornton, Engineering Consultant ...................................................................................................... 07866 815200Jeremy Yarnall, Consultant Engineer ............................................................................................................... 01332 875450

Corporate MembersThe following companies are CORPORATE MEMBERS of the Engineering Integrity Society. We thank them for their continued support which helps the Society to run its wide-ranging events throughout the year.

Bruel & KjaerData PhysicsDatron TechnologyDoosan BabcockGOMHBM United KingdomInstronKemo

LMS UKMillbrook Proving GroundMIRAMOOGMüller-BBMNational InstrumentsPolytecRutherford Appleton Laboratory

New Personal MembersMr C Hulme ...................................................McLarenMs J Pollock ............................Jane Pollock SolutionsMr R Budd ....................... SRL Technical Services LtdMs C Marques ............ London South Bank UniversityMr P Warder ..........................................NDT Services

Safe TechnologyServotestStackTechni MeasureTRaC Global Transmissions DynamicsYokogawa

Committee members

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m+p international (UK) LtdMead HouseBentley, HampshireGU10 5HY, United KingdomPhone: (+44) (0)1420 521222Fax: (+44) (0)1420 [email protected]

Hardware Features:� Modular design from 16 input

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Affordable Performance:� 102.4 kHz sampling rate,

more than 120 dB spurious-free� High-speed Ethernet interface

Proven Application Software:� Vibration control� Shock capture and SRS� Real-time acquisition� Data recording� Modal analysis� Rotational dynamics� Machinery condition monitoring� Acoustics and sound quality� Ground vibration testing

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Engineering Integrity Issue 33

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Transcript of Engineering Integrity Issue 33