不对中联轴器 柔性转子系统非线性动力学行为

主要研究了在滑动轴承支承下转子间具有平行不对中故障的柔性联转子系统非线性动力学行为.首先,在考虑到联轴器的连接刚度后,基于两转子间运动的几何关系和位移约束条件推导了在非线性油膜力作用下平行不对中转子系统的动力学模型,理论分析表明该系统是一个含有时变系数和强非线性特征的11自由度非自治系统.然后采用数值方法重点分析了系统的非线性振动特性,例如,系统的轴心轨迹、频谱相应,Poincaré截面等.结果表明:在较低转速时,转子的涡动轨迹在较小的范围内作同步振荡;随着转速的提高,系统出现倍周期分叉现象,以及准周期、混沌运动等复杂的非线性动力学行为.最后讨论了联轴器的连接刚度对系统运动特性的影响.

Nonlinear dynamics of a flexible rotor system coupled by a misaligned coupling

The dynamic behaviors of a flexible multi rotor system supported on journal bearing with a misaligned coupling were investigated. Firstly, the dynamic model of a rotor system under the action of the nonlinear oil film forces was developed after taking into account the movement relationships and displacement constraint, which describes the misalignment relation between two rotors, and the theoretical analysis reveals that the system with eleven DOF is of strong nonlinear properties and time varying parameter. Then, the nonlinear dynamic characteristics, such as steady state response, rotor orbit, Poincaré section and the largest Lyapunov exponent, were studied. The results show that, at low speed, the orbit synchronously oscillates within a small zone; as the speed increases, the dynamic characteristics become complicated, and the period doubling, quasi period and chaotic oscillations occur. Finally, the effects of the bolt stiffness on dynamic behaviors were also discussed.