为解决航空发动机宽弦空心风扇转子叶片抗鸟撞设计问题,对宽弦空心风扇转子叶片鸟撞损伤进行了数值仿真.采用光滑质点流体动力学(SPH)算法建立鸟体模型,采用J-C本构模型和失效模型定义材料冲击下动态性能,建立旋转状态下叶片鸟撞数值仿真方法,经过试验验证能够较准确预测叶片损伤.开展相同条件下鸟撞击宽弦空心和实心风扇转子叶片仿真,对比鸟撞击叶片过程、撞击时叶片叶尖最大轴向和径向变形、撞击后叶片永久变形,研究被鸟撞击后空心叶片相比实心叶片的损伤特征.结果表明:空心和实心叶片鸟撞击过程相同;空心叶片被鸟撞击后叶尖轴向和径向变形更小;空心叶片被鸟撞击后前缘卷边变形更严重,对风扇气动性能和稳定性影响更大;在结构设计时应适当增加前缘空心区域局部刚度,或者适当增大前缘实心区域范围,用于提高空心叶片的抗鸟撞能力.
The bird strike damage of wide-chord hollow fan rotor blades was studied using numerical simulation to solve the problem of bird strike resistant design.A bird strike numerical simulation method of fan rotor blades in rotating state was established,with the SPH method simulating the bird,and the J-C model with failure defining the material dynamic performance.In addition,the simulation method was validated using experimental results.Comparative simulations between wide-chord hollow and solid fan rotor blades were carried out under the same conditions,and the damage characteristics of hollow blades after bird strike were investigated by comparing the bird strike process,the maximum axial and radial deformation of the blade tip,and the residual deformation with those of the solid blade.The results show that the bird strike processes of the hollow and solid blades are the same;the blade tip radial and axial deformation of the hollow blades are smaller after being struck by the bird.The curling deformation of the leading edges of the hollow blades is more serious,which has a more serious effect on the aerodynamic performance and stability of the fan.The local rigidity of the hollow area or the range of the solid area of the leading edge should be appropriately increased in structural design to improve the bird strike resistance of the hollow blade.