Mechanical Forces Due to Lightning Strikes to Aircraft
Lightning attachment to aircraft occurs on average once every 10,000 hours of flight time.
This project is advertised as part of the EPSRC Doctoral Training Partnership. It is currently not available to self-funded applicants. Find out more information about the DTP including how to apply.
Until recently it has been the high currents (up to 200kA) involved that have been of most concern, with the associated mechanical forces of the acoustic shock, magnetic forces and explosion due to external paint layers seen as less significant. However, with the advent of composite aircraft structures these mechanical forces have become much more important. Accurate quantification of the deflection of a composite plate under lightning strike is important in determining potential damage and consequent reduction in material properties.
A proposed methodology has been developed to estimate the peak acoustic shock overpressure resulting from a lightning attachment. This methodology is based on the use of an optical measurement technique to obtain full field data on the out–of-plane displacement of a panel during lightning strike combined with finite element modelling to replicate these effects and hence enable panel design to be optimised.
Initial work has used high speed video to provide data on the deflection of a single point on the panel under differing levels of strike. This project will build on this using the high speed digital image correlation (DIC) technique to capture this out of plane displacement data across the complete panel.
The data obtained will be used to validate finite element models of the effects of the strike to be used to optimise panel design. Models created in the Multiphysics software COMSOL will be further developed to incorporate the dynamic properties of a range of panels.
The project is linked to ongoing work with Airbus and Hexcel and will be carried out in conjunction with the Morgan Botti Lightning laboratory, a unique facility based at the university and established in collaboration with Airbus for the study of lightning effects on aircraft structures.