WEAVING THE FUTURE

Scientists at the University of Ulster are working on the very fabric of what will be a new generation of lighter - yet stronger - aircraft capable of consuming less fuel but carrying more passengers

THE UNIVERSITY of Ulster is marrying Northern Ireland's traditional strengths in weaving with its latter day technological excellence to develop solutions for the 21st century aerospace industry.

Northern Ireland was once a global centre for the textiles industry and it remains famous for its handmade linens and other fabrics. However, modern technologies and the inexorable shift to lower cost locations in North Africa and Asia led to a long, slow decline for the industry. But a new future is being mapped out for this traditional skills base thanks to pioneering work carried out by the Engineering Composites Research centre (ECRE) at the University of Ulster over the past number of years.

The scientists at the centre are leading research in 3-D weaving of carbon and other fibre composite materials which, increasingly, are being developed to make components for the next generation of aircraft.

This is enabled by ECRE's unique blend of expertise in textile technology, polymer processing and engineering for research into polymeric and composites materials. This expertise can be used in a wide range of engineering applications and it is using this to design new composite materials for use in the aerospace industry.

The multi-disciplinary centre investigates the inter-relationships between materials. It has the capability to take high performance textile yarns such as carbon, aramid, glass and natural fibre through to complex technical textile structures and impregnate them with resins.

Essentially what it does is to take traditional weaving skills and technology to make a fabric from different materials such as carbon or glass. However, traditional fabrics are woven in two dimensions with the threads of material running across the X and Y axes. The materials developed by ECRE are several layers thick and woven in 3-D with an additional thread of material woven across the Y-axis holding all of the layers together.

This makes the material very strong and it becomes stronger still when it is impregnated with resin. This can make it both lighter and stronger than components made of metals such as aluminium. And this is where the aerospace industry comes in.

With oil prices skyrocketing and pressures to reduce carbon dioxide emissions also increasing, the aerospace industry has a heightened interest in any materials which can make aircraft lighter and thereby cut fuel consumption.

"The overall context for the project is the fact that the aerospace industry is driven by costs," explains Tim Brundle, director of innovation with the University of Ulster.

"One way to reduce costs is to reduce the amount of fuel required for flying and this can be achieved by reducing the weight of the aircraft. As a result, the industry has been interested in composite materials for about 25 years now and we have been involved in the research for about 15 years."

This has led to the ECRE team working with some of the biggest names in the aerospace industry including AMRC/Boeing, Rolls Royce, Bombardier and BAE Systems and is now researching five-dimensional woven structures in conjunction with Bombardier, which have the potential for even greater strength and versatility. This 5-D structure not only incorporates the additional thread across the Y access but two further threads at 45 degree angles to it, increasing the strength still further.

"The existence of the aerospace industry locally has been a key driver behind this research," says Dr Alistair McIlhagger, one of the leaders of the research at ECRE.

"What we try to do is gain a fundamental understanding of the key engineering principles involved in the weaving process and the interactions between the different materials and then couple this with science to develop composite materials which can be used to manufacture various aircraft components."

These composite materials can be used for both structural and non-structural components.

The non-structural components include seats, panels and fascias and the structural components include floor beams, traditionally made from aluminium; parts of wings, including leading edges and control surfaces; tail planes, rudders and access panels for engineering work.

Composite materials, including 3D woven composites, could also be used in the manufacture of aircraft engines, offering the potential to increase the efficiency of the engines and to reduce noise.

Among the advantages of these innovative materials are that they are lighter, stronger, have superior fatigue response, and are more cost effective because they lighten the weight of the aircraft, making it possible to carry a greater payload of passengers or freight.

"We are, in part, a mini-manufacturing unit here", McIlhagger points out. "This allows us to look at what we have produced, see how it performs and go into a redesign process to make it better. We can also change the manufacturing process itself to meet the needs of industry.

That is one of the key issues with any type of research like this - it has to be industry backed and more and more you have to take direction from industry. You have to talk to the leading companies to find out what they need and come up with proposals that will offer solutions to their needs."

While ECRE components may not be included in the current generation of aircraft there is every prospect that they will be found in future generations within the next decade. "One of the things about the aerospace industry is that it works very far ahead of itself.

The industry is already looking ahead to 2025 for manufacturing technologies. For safety and other reasons all of these technologies have to be certified and tested and this takes a long time.

Maybe in about five to seven years time you will see components designed using our unique technology being incorporated in aircraft," says McIlhagger.

Tim Brundle agrees. "Rising fuel costs are certainly helping to make this a wonderful business opportunity. When we started out fuel costs were relatively low, now they are at an all time high and still rising.

"This makes the technology very attractive from both the environmental and cost perspectives.

"The other applications should not be forgotten either. The sports industry is a huge market for carbon fibre composites and they are in use in a wide range of goods from golf clubs to racing cycles, from rowing boats and oars to artificial limbs for disabled athletes.

"The potential of the technology is huge and the commercial prospects really are very exciting,"he says. It might just be that 21st century needs will provide the means to grant a new lease of life to Northern Ireland's embattled textile weaving industry.