考虑机体局部刚度影响的前起落架摆振分析

摘要

针对飞机机体局部刚度偏弱导致的摆振问题,建立了一套分析模型.该模型可以分析机体局部弯曲刚度和扭转刚度对起落架摆振临界阻尼、动响应的影响.模型计算结果显示,机体局部弯曲、扭转刚度对起落架摆振临界阻尼影响很大,临界阻尼系数增大一倍以上.将某型飞机起落架参数代入分析模型计算机轮摆角动响应,不考虑机体局部刚度时振动收敛,而考虑机体局部刚度时振动就发散,这与试验结果相吻合,计算和试验结果表明飞机局部刚度偏弱可能导致起落架发生摆振.%Nose landing gear shimmy model because of week fuselage local stiffness is established.The model can analyze the contribution of fuselage local stiffness on the shimmy critical damping coefficient and dynamic swinging response.The results show that shimmy critical damping coefficient can increase to 2 times because of contribution of fuselage local stiffness.The swinging angle response of a landing gear is convergent,but the response of swinging angle considering fuselage local stiffness is divergent.The analysis results accord to the test.