转子-滚动轴承-机匣耦合系统中滚动轴承故障的动力学分析

Dynamic analysis of ball bearing faults in rotor-ball bearing-stator coupling system

针对实际的航空发动机转子系统,建立了含滚动轴承故障的转子-滚动轴承-机匣耦合模型。在模型中,考虑了机匣运动,弹性支承与挤压油膜阻尼的作用,同时,充分考虑了轴承间隙、滚珠与滚道的非线性赫兹接触力以及由滚动轴承支撑刚度变化而产生的变柔性(Varying Compliance)VC振动。在此基础上,建立了耦合系统中滚动轴承外圈、内圈及滚动体的损伤动力学模型,并运用数值积分方法进行了动力学仿真与分析。结果充分表明了本文提出的转子-滚动轴承-机匣耦合系统及滚动轴承故障动力学模型的正确有效性。

At present, in the study of dynamic analysis on ball bearing fault, the effect of rotor is hardly considered, In this paper, aiming at rotor-bearing system of practical aero-engine, a new rotor-ball bearing-stator coupling system dynamic model with ball bearing fault is established. In the model, the stator motion, the flexible support, squeeze film damper （SDF） are considered, and the nonlinear factors of ball bearing such as the clearance of bearing, nonlinear Hertzian contract force between balls and races, and the varying compliance vibration because of periodical variety of contact position between balls and races are modeled. On this basis, the fault models of outer race, inner race and ball in ball bearing are established, and the numerical integral method is employed to obtain system＇s responses, and the vibration characteristics of ball hearing faults are analyzed. The results show the rotor-ball bearing-stator coupling model and the new ball beating fault models are correct and effective.