机动飞行中转子轴承系统新型碰摩的动力学行为

采用考虑转静间隙变化和叶片数的新型碰摩模型,同时考虑转子在机动飞行条件下引起的机动载荷和滚动轴承非线性赫兹接触力,建立了转子-滚动轴承-碰摩耦合系统非线性动力学微分方程.利用数值方法分析了转速和机动载荷对系统动力学行为的影响.研究结果表明:机动飞行条件下碰摩转子系统亚谐波共振幅值增加;低速时,碰摩主要激发高频振动,高速时则激发低频振动;机动载荷增加使转子系统振动增大,从而引起转子与定子间的碰摩.

Dynamics of Rotor Bearing System with New Rubbing Model in Maneuvering Flight

A new rubbing model is proposed， which considers the change in rotor-stator clearance and the number of blades. The maneuver load caused by maneuvering flight and nonlinear Hertz contact force of rolling bearing are also considered. The nonlinear dynamic differential equation of rotor-ball bearings-rubbing coupling system is established by using the finite element method. The effects of rotational speed and maneuver load on the dynamic behavior of the system are analyzed. It is shown that the sub-harmonic resonance of rotor system increases under the rubbing fault. The high frequency components are excited by the rubbing fault at lower speeds， while the low frequency components are excited by the rubbing fault at high speeds. The maneuver load makes the rotor’s vibration increase， which may result in the rubbing fault between the rotor and the stator.