盘轴松动⁃碰摩耦合故障转子系统振动特性研究

STUDY ON VIBRATION CHARACTERISTICS OF ROTOR SYSTEM WITH COUPLING FAULT OF DISC⁃SHAFT LOOSENESS AND RUBBING

转子系统在运转过程中可能会发生零件掉落、松动等情况,导致外加物体与转轴发生碰摩。针对这个问题,考虑盘轴松动与碰摩同时发生的情况,建立具有耦合故障的转子系统有限元模型。利用有限元软件对系统进行仿真,分析盘轴间的松动程度对系统振动特性的影响,并通过试验进行验证。结果表明,转子系统的时域波形周期性变化,频谱以转轴转动频率成分为主。随着盘轴松动程度的加剧,频谱中逐渐出现了高频成分;盘轴转速差在启动阶段的初始值随着松动程度的加剧而逐渐增大;盘心轨迹垂直方向的振动幅值也随着松动程度的加剧逐渐变大,且轨迹形状变得更为复杂。由于碰摩的影响,垂直方向的振动明显受到抑制,其幅值小于水平方向的。研究结果对转子系统耦合故障的动力学特性研究具有非常重要的参考价值。

During the operation of the rotor system,parts may fall and loose,resulting in rubbing between the external object and the rotor shaft.To solve this problem,a finite element model of rotor systems with coupling fault was established by considering the case that disc⁃shaft loosening and rubbing occur simultaneously.Ansys was employed to simulate the rotor system.The influence of the looseness on the vibration characteristics of the rotor system was analyzed.Experiments were carried out to verify the simulation results.The results show that the time⁃domain waveform of the rotor system changes periodically,and the spectrogram mainly contains the first harmonic component.With the aggravation of the looseness,high frequency components gradually appear in the spectrum.The initial value of the speed difference of the disc⁃shaft in the start⁃up phase gradually increases with the aggravation of the loosening.The vibration amplitude of the disc center trajectory in the vertical direction also increases with the aggravation of the looseness,and the orbit shape becomes more complex.Due to the influence of the rubbing,the vibration in the vertical direction is obviously suppressed,and its amplitude is smaller than that in the horizontal direction.The research results have very important reference value for the study on dynamic characteristics of rotor systems with coupling faults.