油膜失稳的非线性振动征兆

On the Nonlinear Symptoms Caused by Oil-whirl or Oil-whip

基于线性振动理论故障诊断技术 ,当故障系统非线性特征明显时常常造成误诊。滑动轴承支撑的转子系统的油膜失稳故障是最常见的非线性振动故障。本文建立轴承转子系统的非线性振动模型和状态方程 ,应用 Matlab系统的 Rounge- kutta法求状态方程的特征乘数 ,编程求解 L yapunov指数。根据 Floquet理论和 L yapunov指数判定系统运动状态 ,求解一系列参数条件下系统响应的数值解 ,以数值解与状态转迁集所表明的系统状态一致证明状态转迁集可以用于指示系统运动状态 ,指导故障诊断。

When the system have obvious nonlinear factors,t he fault diagnosis technology based on the theory of linear vibration often caus es error diagnosis conclusion. Oil-whirl or oil-whip of rotor system supported by sliding is a quite usual nonlinear vibration fault. This paper gives the vib ration equations of the bearing-rotor system, and then gets the characteristic multiplication factors by Rounge-Kutta method in Matlab system.According to the ories of Floquet and Lyapunov,state of the vibration system is decided. The over all skeleton of the system states, called set of state changes, is obtained by a series of characteristic multiplication factors and Lyapunov exponent with diff erent system parameters. The numerical solution of the system and the states dec ided by the set of state changes show that the set of state changes could be use d to demonstrate the vibration state of nonlinear system and guide fault diagnos is.