直升机桨叶扬起下坠过程碰撞模型影响研究

The effect of contact models between the blade and droop stop on the dynamic response of the blade droop stop impact

为研究直升机桨叶扬起下坠接触过程动力学问题,根据Hamilton原理建立桨叶扬起下坠过程的动力学方程,并用Newmark积分法求解了桨叶动响应。用等效碰撞模型和有限元模型模拟桨叶与限动块间的碰撞,对比分析不同碰撞模型时桨叶的动力学响应。研究结果表明:等效碰撞模型的动响应计算结果与试验值吻合较好,桨尖最大负向位移误差为2.07%,响应时间误差为7.40%;有限元模型计算结果与试验值吻合更好,桨尖最大负向位移误差趋近于0,响应时间误差为2.82%;等效模型分析结果趋于保守,可用于桨叶扬起下坠问题工程分析。

To investigate the dynamics during the contact between the helicopter blade and the droop stop,the dynamic equations of the system are derived by Hamilton's principle.The dynamic responses during the droop stop impact are obtained by Newmark integration method.The equivalent model and finite element model are used to model the contact between the blade and the droop stop,and the dynamic responses of the blade are analyzed.The results show that the predicted dynamic responses of the equivalent model are in good agreement with the test data,with the maximum negative tip displacement error being 2.07%,and the response time delay being 7.40%.The predicted dynamic responses of the finite element model are in better agreement with the test data,with the maximum negative tip displacement error approaching zero and the response time delay being 2.82%.The equivalent model can give conservative prediction of the responses,which can be applied in the analysis of dynamic responses of blade droop stop impact.