支承松动的质量慢变转子系统混沌特性研究

建立了带有支承松动故障的质量慢变转子系统的动力学模型，利用数值积分和Poincare映射方法，对该转子系统由于支承松动故障而导致的动力学行为进行了数值仿真研究。给出了系统响应随转子转动频率变化的分岔图、最大Lyapunov指数曲线图、典型的Poincare截面图和幅值谱图等，以及质量慢变系数对系统响应影响的分岔图。结论表明：转子的横向均为多周期运动，纵向响应几乎均为混沌运动；随着转动频率的增加，转子的振动幅度出现波动，而在2倍固有频率处达到极小值；质量变化幅值系数的增加致使混沌运动的频率区间增大等。

Study on Chaos Behaviors of Rotor Systems with Slow-varying Mass and Pedestal Looseness

A dynamic model of the rotor system with slow-varying mass and pedestal looseness was set up. The nonlinear dynamic behaviors were studied, which were caused by joint effects of pedestal looseness and slow-varying mass using numerical integration and Poincare mapping method. The bifurcation diagrams and maximal Lyapunov exponent maps were given about the response changes with the frequency ratio, and the dynamic behaviors influenced by the slow-varying mass coefficient were analyzed. The conclusions indicate that horizontal response of the rotor is P-n motion, and vertical response is almost chaotic motion; with the frequency increasing, vibration range of the rotor has appeared to rise and fall, and achieves one tiny value at 2 times of intrinsic frequency; the increase of mass varging coefficient causes enhancement of the frequency region of Chaotic motion, etc..