滚动轴承径向游隙对支承不同心柔性转子系统 动力特性的影响

Influence of Rolling Bearing Radial Clearance on Dynamic Characteristics of Flexible Rotor System withSupporting Non-Concentricity

中文关键词:  滚动轴承  径向游隙  支承不同心  柔性转子  动力特性  整机振动  航空发动机

英文关键词:rolling bearing  radial clearance  supporting non-concentricity  flexible rotor system  dynamic characteristics  whole engine vibration  aeroengine

中文摘要:

      为研究滚动轴承径向游隙对支承不同心柔性转子系统动力学响应的影响规律，针对涡轴发动机的动力涡轮转子设计了 动力相似柔性转子试验器。调节前后轴承座水平偏心距离，直至转子响应中出现较明显的2倍频；各支点依次更换为不同径向游 隙的滚动轴承并开展不平衡响应试验；对比不同径向游隙、不同测点响应中基频、2倍频幅值变化规律，基于控制变量法利用柔性 转子试验器开展了一系列试验研究，分析不同支点处滚动轴承径向游隙对转子振动响应的影响规律和机理。结果表明：在试验中 观察到“频率锁定”现象，以及由其导致的转子共振；合适的滚动轴承径向游隙组合可大幅降低转子系统振动，最大减振幅度可达 85%；径向游隙的减振机理为补偿支承不同心引起的附加不平衡力、力矩，但不同轴向位置处轴承对二者的补偿效果不同，导致减 振效果不同。研究结论对航空发动机整机振动控制具有重要的工程应用价值。

英文摘要:

      In order to investigate the influence of radial clearance of rolling bearings on the dynamic response of a flexible rotor system with supporting non-concentricity, a dynamic similar flexible rotor test rig was designed based on the power turbine rotor of a turboshaft engine. Firstly, the horizontal offset of the front and rear bearing housings was adjusted until an obvious 2X frequency component can be observed in the response. Then rolling bearings with different radial clearances were sequentially replaced at each support, and the unbalance response tests were conducted. Finally, a series of experiments were conducted using the control variable method and the flex? ible rotor test rig, by comparing the variations of amplitudes of 1X and 2X in the responses of different measuring points under different radial clearances, the influence and mechanism of rolling bearings radial clearance on rotor vibration responses at different supports were analyzed. The results show that the phenomenon of "frequency locked-up" and the resulting resonance can be observed during the experi? ments; Appropriate combinations of rolling bearings radial clearances can significantly reduce the vibration of the rotor system, with a maximum reduction of vibration amplitude over 85%; the vibration reduction mechanism is that the radial clearance could compensate for additional unbalance forces and moments caused by supporting non-concentricity, however, the compensation effects of the bearings at dif? ferent axial positions varies, resulting in different vibration reduction effects. The findings of the research are of significant engineering value for the vibration control of the aeroengine.