松动碰摩转子轴承系统周期运动稳定性研究

根据松动碰摩耦合故障转子轴承系统的非线性动力学方程，利用求解非线性非自治系统周期解的延拓打靶方法，对系统周期运动的稳定性及其失稳规律进行了研究，得到了系统在不平衡量-转速、碰摩间隙-转速等参数域内的分岔集。分析表明：在较大和较小的不平衡量下，系统的周期运动分别以Hopf分岔形式和倍周期分岔形式失稳；耦合故障转子轴承系统表现出与碰摩转子轴承系统相似的分岔失稳规律；随着系统动静件之间的碰摩间隙减小，系统的Hopf分岔集区间变大而且失稳转速降低。该结论可以为转子系统的故障诊断、安全稳定运行及振动控制提供理论依据。

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

Based on the nonlinear dynamic model of rotor-bearing system with rub-impact and pedestal looseness, the stability of the periodic motion of the system is studied by continuation-shooting method for the periodic solution of nonlinear non-autonomous system. The bifurcation point sets in the unbalance-rotating speed and clearance- rotating speed plane are obtained. The following conclusions are drew: The periodic motion of the system lose stability by Hopf and doubling bifurcation respectively under both small and large unbalance; the system with couple faults has the same discipline of losing stability as the system with rub-impact. The Hopf bifurcation point set is broadened as the clearance between rotor and stator decreases. The results of the paper may provide theory references to fault diagnoses, vibration control and safety operating of the rotor system.