滚动轴承非线性轴承力及其对轴承系统振动特性的影响

滚动轴承在旋转机械中应用及其广泛,其振动特性对旋转机械的正常运行有很大影响.本文基于赫兹弹性接触理论和滚动轴承运动学,推导了滚动轴承在工作状态下产生的非线性轴承力,并在此基础上对滚动轴承系统的振动特性进行了分析.研究结果表明:滚动轴承的非线性轴承力会诱发变刚度振动.系统响应中存在多种周期(谐波、次谐波和超谐波)和非周期(拟周期和混沌)响应.通过频谱图、Poincare图和分叉图,分析了滚动轴承系统在不同参数下的周期分叉特性.当非线性轴承力和不平衡力共同作用时,滚动轴承系统会产生组合振动,随着不平衡力的增大变刚度振动所对应频率的幅值逐渐降低.

Non-Linear Bearing Force of the Rolling Ball Bearing and Its Influence on Vibration of Bearing System

Rolling ball bearing is widely used to support rotors.It is a non-negligible source of vibration in many types of rotating machines,so the vibration characteristics of the rolling ball bearing system is worth to be investigated.Hertz elastic contact theory and bearing kinematics theory were applied to calculate the force caused by the rolling ball bearing.The non-linear vibration of rotors supported by the rolling ball bearing was studied.It was found that the non-linear bearing force excited the varying compliance vibration.Many kinds of periodic(synchronous,sub-and super-synchronous) and non-periodic(quasi-periodic and chaotic) responses exist in the system.The periodic bifurcation behavior of the system was analyzed by means of spectrum diagrams,Poincaré maps and bifurcation diagrams.When non-linear bearing force and unbalance force act simultaneously,combined vibration will be generated.With the Increase of unbalance force,the varying compliance vibration will be weakened.