含松动-碰摩耦合故障转子系统的动力学特性研究

STUDY ON THE DYNAMIC CHARACTERISTICS OF A SYSTEM WITH A LOOSE-RUBBING COUPLED FAULTY ROTOR

建立了含松动及碰摩多重故障耦合的转子系统动力学模型。采用四阶Runge-Kutta法进行数值仿真,得到了转子系统周期分岔图、最大碰摩力曲线图、松动轴承支座振幅图以及相图和Poincaré映射图,重点分析了松动质量对系统动态特性的影响。研究表明,松动故障使得转子系统在较低转速进入碰摩运动;亚谐运动、概周期运动、混沌运动的转速区间增加,同时与之对应的最大碰摩力、松动支座振幅较大。较大的松动质量可以降低松动轴承支座的振动幅值,同时使得系统在低转速较长区间处于无碰摩的周期一运动,有利于系统在故障条件下处于稳定状态。

A dynamic model of rotor system with loosening and rubbing multiple faults coupling was established.Fourth-order Runge-Kutta method was used for numerical simulation.Periodic bifurcation diagram of rotor system,maximum rub-impact force diagram,amplitude diagram of loose bearing support,phase diagram as well as Poincaré map of the rotor system were obtained.The analysis was focused on the influence of loose mass on the dynamic characteristics of the system.The research shows that the looseness fault makes the rotor system enter the rub-impact motion at low speed.The rotational speed range of subharmonic motion,almost periodic motion and chaotic motion increases.At the same time,the corresponding maximum friction force and loose support amplitude are larger.The large loose mass can reduce the vibration amplitude of the loose bearing support.At the same time,it can make the system in the periodic motion without rub-impact in the long range of low speed,which is conducive to the stable state of the system under fault conditions.