转子—轴承系统的稳定性,分岔与混沌行为研究

利用修正的短轴承理论模型对转子－轴承系统进行了稳定性、分岔与混沌特性分析。结果表明：系统平衡失稳时产生迟滞超临界Ｈｏｐｆ分岔，由于迟滞的存在，使得迟滞区内系统拓扑结构的等价性在大扰动下可能被被破坏，因此，线性理论无法解释该区段内的动态行为。存在不平衡量时，系统失稳可能产生拟周期分岔、倍周期分岔并可能导致混沌振动。这些结果为控制转子的稳定运行状态提供了依据，为油膜失稳故障的诊断提供了有益的启发。

Research on Stability Bifurcation and Chaos of a Rotor Bearing System

The stability,bifurcation and chaos of a rotor bearing system is analyzed by using the modified short bearing approach.Calculation results show that the instability of the balanced rotor bearing system motion belongs to hysterics supercritical Hopf bifurcation.Because of hysterics,the topological equivalent may be wrecked in large disturbance.So the dynamic behaviour of the system can not be analyzed by linear theory.The instability of the unbalanced system motion may result in doubling period bifurcation,almost periodic motion and chaotic motion.The results of the paper provide theoretical basis for the control of the stable operation of the system,and some inspiration of making a correct diagnosis on the oil instability fault can be derived from the analysis.