闭式齿轮传动系统内部动态响应的有限元法预测

FEM Prediction for the internal dynamic response of closed gear transmission system

针对闭式齿轮传动系统动态分析理论求解复杂,试验方法只能测得表面振动数据的问题,对某二级行星减速器进行三维建模生成有限元模型,完成有限元模态分析;通过模态试验,验证了模拟的正确性;利用ANSYS瞬态动力学分析的完全法(full),考虑时变啮合刚度、综合啮合误差、齿侧间隙及阻尼比等非线性因素的影响,实现了动态模拟和台架试验对比。研究结果表明:有限元法所得前六阶固有频率与试验结果接近,频率最大误差为8.12%,振型吻合;动态模拟结果与台架试验测得的振动加速度平均值误差较小,振动规律基本一致。以此为依据,获取了输入端与输出端的振动加速度和齿圈啮合点应力变化曲线,与工程实际相符,有限元预测方法可弥补试验法在分析内部振动响应方面的不足。

The current test method can only measure the surface vibration data in dynamic analysis on the complexity of closed gear transmission system. Taking a secondary planetary gear reducer as investigation object,it builds its 3D model and finite element model,simulates its working characteristic,carries the corresponding experiment to verify its FEM model. It compares the bench experiment and dynamic simulation in the nonlinear influence of time- varying meshing stiffness,comprehensive meshing error,backlash in circular tooth and damp ratio based on full transient dynamic analysis software ANSYS. The results show that the first six order natural frequencies gained from finite element method are close to the experimental results,and maximum error of frequency is 8. 12%. The errors between simulation results and vibration acceleration obtained from bench experiment are small,and vibration tendency is almost coincident. Based on above,accelerations of output and input ends and stress of meshing point of gear ring picked up from FEM model coincide with practical application. This method makes up for a deficiency of internal vibration response in conventional experimental method.