考虑机体弹性的起落架着陆仿真分析

Simulation of Landing Gear Drop Considering Flexible Airframe

首先建立机身的有限元模型,该模型的模态与全机地面共振(GVT)试验测得模态相吻合。然后分析起落架缓冲器受力,并编制程序,计算出相关的曲线,LMS仿真平台调用上述曲线对单个起落架进行仿真,在单个起落架仿真结果与落震试验结果吻合的基础上,对某型飞机进行刚性机身全机落震仿真分析。最后调用机身有限元模型进行柔性机身全机落震仿真分析,对刚性机身、柔性机身全机落震仿真结果进行对比,结果表明:柔性机身全机着陆起落架载荷峰值比刚性机身载荷峰值降低,起落架功量图更为平缓。该方法可为起落架设计提供更加准确的设计参考。

The finite element model of flexible airframe is created firstly,its mode coincide with leuven modal test system（GVT） test.Then the buffer force is analyzed and program is compiled to calculate the relevant curve.On the LMS simulation platform a single landing gear drop is simulated by using this curve.Based on the single landing gear drop simulation,which coincides with the drop test,the whole aircraft drop test simulation is done including rigid airframe and flexible airframe.Through the comparison of the two results,it shows that the flexible peak load is lower than the rigid one,and the landing gear energy absorb chart becomes more gently.This method can thus provide more accurate design reference for landing gear design.