多圆盘转子系统的周期运动及其稳定性分析

采用短轴承理论方法 ,把油膜力作为转子系统的约束力加入到转子的动力学方程中 ,分析了多圆盘转子系统在非线性油膜力作用下的周期性运动及稳定性。对转子系统的周期运动 ,使用近似级数表达形式 ,对于非线性的油膜力 ,根据周期运动的特点 ,采用周期级数展开形式 ,求解了非线性动力学方程 ,得到了转子的周期运动轨道。在分析周期运动的稳定性时 ,采用谐波平衡方法 ,得到转子周期运动的稳定条件 ,为工程设计提供了一定的依据。最后对刚性非平衡对称支承单圆盘的周期运动及稳定性进行了数值模拟 ,证明了本文方法的有效性

Periodic Motions and Stability Analysis of Rotor Systems with Multiple Disks

On the basis of the short bearing theory, the fluid film forces are considered as constraint forces and added to the rotor dynamical equations. The periodic motions and stability of rotor systems are studied under the nonlinear fluid film forces. An approximate serial expression is used for the periodic motions of rotor systems. According to the characteristic of periodic motions, the periodic serial expression is also adopted for the nonlinear fluid film forces. Thus, the nonlinear dynamical equation can be solved and the periodic motions are obtained. To study the stability of periodic motions the harmonic balance method is used. The condition for the stability of periodic motions can provide a theoretical basis for the design of rotor systems. At last the numerical simulation of a symmetrical, unbalanced and rigid rotor subjected to a constant vertical load and supported on two lubricated journal bearings shows the availability of this method.