Modeling Bird Impact on a Rotating Fan : The Influence of Bird Parameters

The ability to withstand bird impact is one of the major requirements of the modern aircraft jet engine. In fact, rigorous certification procedures are put in place to assess the engine’s ability to sustain severe impact loads developed during bird impact. Full scale bird tests are expensive and time consuming, and call for the use of accurate numerical approximations during the design stages of engine development. The main difficulties encountered in achieving accurate finite element (FE) analysis are related to modeling of the bird which undergoes severe deformations, and modeling of the contact between the bird (soft) and blade (stiff) materials. Thus far Smooth Particle Hydrodynamics (SPH) modeling in LS-DYNA, which is a meshless method, had shown potential in adequately modeling the bird and the bird-blade interactions. Recent publications also show the ability of SPH based models to capture impact strains and forces seen by the rotating fan blades [1, 2]. The current study further investigates the interaction of the SPH bird with the FE blades, and the ability of the model to capture realistic blade deformation. The main emphasis is placed on the effect of the bird related parameters on the damage sustained by the blades.