Dynamics of Rotor-Bearing System with Coupling Faults of Pedestal Looseness and Rub-Impact

摘要

The dynamical model of elastic rotor-bearing system with coupling faults of pedestal looseness and rub-impact is formulated by using modem nonlinear dynamics and rotor dynamics. In view of the strong nonlinear characteristics of the oil film force in the short bearing and the coupling faults of the rotor-bearing system, the system is numerically studied by using Runge-Kutta method. The bifurcation diagrams with rotating speed as controlling parameter, some representative figures of Poincare sections, journal center trajectories and frequency spectrum diagrams are provided. It's found that rub-impact affects the dynamics of the coupling faults system much when rotating speed is near the first order critical speed. When rotating speed is high, the dynamics of the coupling faults system resembles that of the pedestal looseness rotor system. The results may bring up theoretical references for the fault diagnosis of rotor-bearing system with coupling faults mentioned above.