摩擦系数对轴向推力作用下碰摩转子振动特性的影响

推导建立了轴向推力作用下的碰摩转子非线性动力学方程。以转定子间摩擦系数为控制参数,对碰摩转子系统横向振动和轴向振动行为进行了数值仿真。分析表明:转子与定子间摩擦系数对转子系统横向振动和轴向振动特性的影响非常明显,摩擦系数越大,转子系统振动越复杂。随着摩擦系数的增加,转子系统由简单的周期振动突变为拟周期振动。增大摩擦系数,以转速比为控制参数的系统轴向振动的复杂运动区范围变大,且复杂运动区的振动幅值也有增大趋势。分析结果对旋转机械碰摩故障的识别提供了理论依据。

Influence of friction coefficient on vibration characteristic of rub- impact rotor with axial thrust

A model of a rigid rotor system with rotor-to-stator was established based on the classic impact theory and was analyzed by the Lagrangian dynamics.The rubbing condition was modeled using the elastic impact-contact idealization,which consists of normal and tangential forces at the rotor-to-stator contact point.Nonlinear dynamic behaviors of rub-related vibrations were studied with numerical simulations.The effect of friction coefficient of rotor-to-stator on the rigid rotor response was investigated in detail.It was demonstrated that both lateral vibration and axial vibration were strongly influenced by the friction coefficient of rotor-to-stator.The larger was friction coefficient of rotor-to-stator,the more complicated the rotor vibrations.Large friction coefficient could excite complicated quasi-periodic vibration from simple periodic vibration.These forms of dynamical characteristics could be effectively used to diagnose the rub-impact fault.