基于接触分析的转定子系统整周碰摩故障模拟

FULL RUBBING SIMULATION OF A ROTOR-STATOR SYSTEM BASED ON CONTACT ANALYSIS

以一个单跨双盘柔性转子系统为研究对象,建立转子系统的有限元模型,基于接触动力学理论,将转子和定子简化为一个点-点接触单元,通过转定子间的圆形间隙变化来模拟转定子的分离及整周接触,并通过碰摩力耦合转定子模型,采用增广的拉格朗日方法处理接触约束条件,用库仑摩擦模型模拟转定子之间摩擦,考虑不同转速、转定子间隙、转定子法向接触刚度、阻尼和摩擦系数对转子系统动力学特性的影响。研究结果表明:转速和转定子法向接触刚度对系统响应影响最大,转定子法向接触阻尼和摩擦系数次之,转定子间隙影响最小。

A single span flexible rotor system with two discs is investigated and a finite element model of the rotor-bearing system is established. By simplifying one disc and its corresponding stator as a point-point contact element to simulate rotor-stator rubbing, rotor-stator separation and full circle contact is determined by the change of cylindrical gap and the rotor and stator model are coupled by nonlinear contact force. By adopting the augmented Lagrangian method to deal with contact constraint conditions and coulomb friction model to simulate rotor-stator frictional characteristics, the responses of the rotor system with rubbing are analyzed. The effects of rotating speeds, rotor-stator gap, rotor-stator normal contact stiffness, damping and friction efficient on normal rubbing forces and vibration responses are discussed. The results show that the rotating speed and rotor-stator normal contact stiffness have the greatest effects on the rubbing force, and the rotor-stator contact damping and friction efficient have less effect, while the rotor-stator gap has only minimum effect.