New ways to look at degradation
Alan Dron reports on new research, which is looking to develop high-value manufacturing products with longer functional life and lower whole-life cost.
Anyone who owns a modern colour printer to hook into their laptop or desktop computer knows that buying a new model today is remarkably cheap; buying the replacement ink cartridges over the next three years is where the greater expense arises.
It’s much the same story in the aerospace and defence sectors, only on a hugely larger scale. For years now, airlines and armed forces have focused increasingly on the whole-life costs of major items of equipment, rather than the up-front ‘sticker price’.
This has now reached the point where airlines – especially those that operate pre-used aircraft – often now part out a 15-year-old airliner rather than pay the costs involved in a C- or D-check engine overhaul.
Reducing those aftermarket costs is one of the areas under study as part of a five-year research project that began in April this year, headed by Professor Rajkumar Roy, director of manufacturing, academic and business support, at Cranfield University.
The planned research is part of a long-term agenda to develop high-value manufacturing (HVM) products with longer functional life and lower whole-life cost. The research is aimed at supporting the recently published national strategy on engineering services and a 2025 vision of achieving a 20% reduction in whole-life cost with a 20% increase in availability during the life of a product.
High-value products are typically technology-intensive, expensive and reliability-critical pieces of equipment – aircraft engines or defence equipment, for example – that require engineering services such as maintenance, repair and overhaul throughout their life-cycles.
“This is my main area of research,” said Roy.
“It’s more than maintenance; it’s basically looking at all sorts of technologies that are necessary to guarantee performance through life with an optimum cost. It’s for complex engineering systems.”
The research focuses on ‘degradation studies’, or factors that lead to a decline in performance of those engineering products over time. Cranfield is already a centre of excellence in this field.
“At a through-life engineering services centre, we’re looking at new ideas in modelling and assessing degradation,” explained Roy.
A particular focus is studying degradation that is the result of multiple, parallel factors. One example would be fatigue cracks and corrosion occurring together and the effect that temperature has on these factors.
The team is trying to do this in situ, for example, without removing an aircraft engine from its location, through very small service access holes. The ability to do so would obviously greatly reduce the time, and thus cost, involved.
Making things work
Part of the driving force behind the project is a paper, produced by Cranfield University in 2015, entitled: Making Things Work. Engineering for life – developing a strategic vision. This recognised that the UK had a declining 5% share of a rising global market in service and support that currently exceeds £490 billion. That market is estimated to grow to £710 billion by 2025.
Today, more than 50% of revenue in the aerospace and defence sectors comes from the service contracts, a prime example being Rolls-Royce’s Total Care contracts and related support activities.
The UK Government recognises the importance of developing engineering services and support capability, but also recognises there is little underpinning science and good practice available to the extended service supply chain needed for UK competitiveness and productivity.
The five-year research project is being funded with a £1.2 million grant from the Engineering Physical Sciences Research Council (EPSRC).
The aim of the grant, said the EPSRC, is to sustain “a world leading team with strategic researchability on through-life performance improvement”, including complex in-situ degradation assessment technologies.
The team, which combines personnel from Cranfield and Nottingham Universities, has worked together over the last 10 years. “This research will develop the team as an international centre of excellence in through-life performance improvement and is the only research group internationally focusing on this area in respect of HVM.”
The EPSRC noted that current research capabilities still focus upon single degradation modelling and assessment and that there remains “a significant lack of knowledge and models for compound degradation”.
The research team will be supported by partner organisations, including Rolls-Royce and Bombardier.