鸟体形状及撞击方向对鸟撞分析影响较大。真实鸟体形状复杂，不同鸟类外形、大小各异，研究中常用简化替代模型模拟。4种常见鸟体替代模型为球体、圆柱体、两端半球－中间圆柱体及椭球体。实际鸟撞事故中，鸟可能从头、尾、翼及腹部等不同方向撞击飞机，所致影响不尽相同。对此，建立真实形状鸟体撞击刚性靶有限元模型，研究不同撞击方向对鸟撞分析影响；进行4种简化鸟体替代模型分析，并与真实形状鸟体分析结果对比，研究替代模型对真实形状不同撞击方向的适用性。结果表明，不同撞击方向对分析结果影响较大，腹部冲击力极值最大，冲击持时最短；头、尾部冲击极值较小。腹部冲击动能衰减最快、最多，尾、翼部次之，头部最慢。尾部与两端半球－中间圆柱体撞击计算结果吻合较好；腹部与椭球体长边侧撞击计算结果吻合较好；头、翼部与替代模型计算结果吻合较差。%Birdshapeandstrikeorientationaretwoveryimportantfactorsaffectingtheaccuracyofbirdstrike analysis.The realistic bird has a complex configuration and there are different bird types with different body shapes,so researchers often use simple configurations to model birds in bird strike events.There are four substitute bird models most-frequently employed in literatures,they are sphere,straight-ended cylinder,hemispherical-ended cylinder and ellipsoid. During a bird strike event,a bird can strike an airplane from its head,tail,abdomen or wings.These orientations have different effects on the response of an airplane part.Firstly,a realistic bird model was established to study the effect of its strike orientation.The results obtained by using the four substitute bird models were compared with those using a realistic bird model in order to determine the best substitute bird model for modeling the force exerted by a real bird with different strike orientations.It was shown that the striking orientation of a bird has a big influence on the impact force;the impact force obtained by striking from abdomen is the largest and the impact duration is the shortest while those obtained by striking from head and tail are relatively less;meanwhile,the kinetic energy loss of bird tends to be most and fastest for striking from abdomen,for strikings from wing and tail they are second,for striking from head it is the smallest;besides, for string from tail,a hemispherical-ended cylinder model has the best results and for striking from abdomen,an ellipsoid model striking from its long side is the best substitute model,while for striking from head and wing,no substitute models are better.
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