The influence of bird-shape in bird-strike analysis

This paper describes the results of simulations to assess the influence of bird shape during bird-strike. In the first part of this paper, simulations are presented which compare the results of a traditional bird shape model (hemispherical ended cylinder) impacting a square flat panel using the ALE and SPH techniques. In each case the bird is modelled with a mass of 8 lb and has physical dimensions (torso) representative of a Canadian goose. The simulation results show close agreement with one another for stagnation pressure and displacement of the panel. Biometric data obtained from the IBRG (International Bird-Strike Research Group) is then used to construct a more detailed bird model of a Canadian goose that includes multi-material parts. The model is simulated using SPH and compared to the results of the hemispherical ended cylinder. The simulation results obtained using this new bird model indicates that a target may become pre-stressed from the initial impact of the head and neck, prior to the impact of the torso. This may have an important consequence for damage initiation and failure of the target.