Better use of composites in aircraft from predicting crack growth

New codes developed at Imperial College London form the basis of the computer model that will let designers explore damage tolerance in much greater detail and bring advantages such as reduced development cycles and R&D costs, plus lighter, more fuel-efficient aircraft.

The project, undertaken with partners Airbus and funded by EPSRC, sought to predict how cracks propagate through a composite part when subjected to anomalous events such as bird strike or an extremely large turbulent flow.

‘It is true that composite materials have cracks within them with lengths in the order of micrometres, and those cracks are everywhere and aren’t something to be worried about,’ explained project leader Dr Silvestre Pinho. ‘The focus of this work was in situations where cracks actually grow so that we can predict how they grow.’

Carbon fibre reinforced composites are an attractive structural material because they are lighter than the metals they replace and possess favourable strength-to-weight and stiffness-to-weight ratios.