滚动轴承-转子系统动力学特性分析

Analysis on Dynamic Characteristics of Rolling Bearing-Rotor System

在滚动轴承动力学和转子动力学基础上,建立滚动轴承-转子系统非线性动力学分析模型,采用New-mark-β积分法和Newton-Raphson迭代法对轴承-转子系统非线性动力学微分方程进行求解,对轴承结构参数和工况参数与轴承-转子系统动力学特性关系进行分析,分析结果表明:系统中转子的转动频率始终存在,支承轴承的变刚度频率随着轴承结构参数和系统工况参数的不同而出现或消失;支承轴承内、外沟曲率半径系数的变化不改变系统中已存在的振动频率成分;系统的非线性特性随轴承钢球个数、预紧力的增加而减弱,随径向载荷的增大而增强;存在一个最佳转速区间,在此区间内,系统的非线性特性较弱。

Based on the rolling bearing dynamics and rotor dynamics, the nonlinear dynamic analysis model is estab-lished to describe the rolling bearing - rotor system. Newmark - β integral method and Newton - Raphson iterative method are used to solve the nonlinear dynamic differential equations of bearing - rotor system. The influences of bearing geometric parameters and working conditions on the dynamic characteristics of bearing - rotor system are analyzed. The results show that ： The rotation frequency of rotor always exists in the system, the varying stiffness frequency of sup- porting bearing appears or disappears with different bearing geometric parameters and system working conditions;the vi- bration frequency components existing in the system are constant regardless of the change of groove curvature radius co- efficients of inner and outer rings ; the nonlinearity of the system is weakened with the increase of ball numbers and preload force and enhanced with the increase of radial force;there is an optimal rotation speed zone, in which the nonlinearity of the system is weak.