风扇叶片冰撞仿真方法与试验

Simulation method of hail impacting on fan blades and experiments

采用光滑粒子流体动力学法和拉格朗日法对冰撞过程进行仿真分析,开展了冰雹撞击钢板、撞击钛合金薄板、撞击非旋转态真实风扇叶片的打靶试验验证。结果表明:采用的考虑压缩强度与应变率相关的冰雹本构模型和SPH法能够很好的描述冰雹撞击过程,仿真结果与打靶试验结果吻合良好。基于该本构模型和算法,对某发动机在爬升状态下吞入直径1.1 cm的冰雹情况进行仿真,揭示了叶片不同部位冰撞后的变形情况,发现撞击叶尖部位带来的塑性应变最大。开展整机吞冰试验,试验获得的冰雹撞击部位的叶片变形长度与仿真结果误差小于10%。改进了叶片前缘半径和最大厚度分布,提升了叶片的抗冰撞能力,为风扇叶片抗冰撞改进设计积累了良好的设计经验。

Smooth particle hydrodynamics(SPH) method and Lagrange method were used to simulate the process of hail impacting and the experiments of a Hail impacting on a plate,a titanium alloy sheet and a real fan disk were carried out.The results showed that the high strain rate constitutive model and Smooth particle hydrodynamics(SPH) method could simulate the process of hail impacting precisely;the simulation results had a good agreement with the experiment results.Based on this constitutive model and method,simulation of a hail of 1.1 cm diameter impacting into an aero engine at the state of climbing was carried out and the deformation of the blades after impacting was revealed.The result showed that impacting on the tip site of the blade would have the worst situation of plastic strain.An aero engine hail impacting test was carried out,and the deformation error of the impacted blade and simulation results was less than 10%.The front edge radius and the maximum thickness distribution of the blade were improved,and the anti-hail impacting ability of the blade was enhanced,and the improved design experiences had been accumulated for anti-hail impacting.