Dynamic response of bird strike on variable stiffness laminates of composite leading edge

Abstract

The research evaluated constant stiffness (CS) and variable stiffness (VS) laminate composites using two simulated situations: static and bird strike analyses. The first example demonstrates that a plate with a hole exhibits better strength and stiffness when using VS laminate. The continuously changed fibre orientation creates variations in stiffness at different locations, allowing designers to adjust the distribution of internal loads to improve structural performance or reduce weight. The second example indicates that VS laminate skin on a wing's leading edge exhibits better resistance to bird impacts. This is because compared with the CS lay-up of composite materials, this kind of the VS lay-up (asymmetric unbalanced lay-up) makes the material matrix to have some nonzero coupling items, which is conducive to improving the impact resistance of the structure. Simulation results show that these VS composites reduce deformation and stress induced by bird strikes without increasing the weight or size of the components or adding additional structure.