转子-基础系统的随机不确定建模与振动分析

以具有基础弹性支承的Jeffcott转子为研究对象,并考虑到外部随机激励对基础的作用和转定子间的碰摩现象,建立了带碰摩故障的转子-基础随机外激励系统的动力学微分方程.应用相应的数值仿真方法,给出了该系统随外部随机激励变化影响下的轴心轨迹、频谱图和Poincaré图等;分析了随机外激励的变化对转子-基础系统的影响.结果表明随机外激励强度和谱宽的变化以及周期外激励频率的改变将引起振动模式(如频率和波形等)的改变,并将导致转子出现周期、倍周期和混沌等复杂的动力学行为. 

Random uncertainty modeling and vibration analysis of rotor-foundation system

Taking the Jeffcott rotor with elastic support as the research object, the dynamic differential equation of rotor-foundation external random excitation system with rubbing faults was built in consideration of the effect of the external random excitation on the foundation and rubbing faults between stator and rotor. The numerical simulation was employed to obtain the system responses with the effect of the external random excitation, and the axis orbit, frequency spectrum and Poincaré sections were used to anlyse the effect on rotor-foundation system with the variation of the external random excitation. The results show that: the vibration mode (such as frequency and waveform) could be changed by the intensity and spectral width of the external random excitation and frequency of the external periodic excitation. And it will cause complex dynamic behaviors of rotor such as cycle, period doubling and chaos.