转子系统油膜失稳故障的振动实验分析

在单跨转子实验台上对油膜失稳故障(油膜涡动和油膜振荡)进行实验,分别对发生油膜失稳的转子稳定运行过程和转子升降速过程进行了振动测试·在油膜振荡期间,转子振动的时域波形呈现复杂的多周期性特点,轴心轨迹为扩散的不规则曲线,功率谱与全息谱表现出明显的分频(0 44倍频)特征·转子升降速过程的时频域分析揭示了转子油膜由涡动到振荡的发生发展过程·实验与分析的结果对研究转子油膜失稳故障现象、实现旋转机械的状态监测与预报有重要意义·

Experimental Analysis on Vibration of Rotor System with Oil-Film Instability Fault

Experiments were carried out to investigate the oil-film instability fault behaviors, including oil-film whirling and oscillating, on a special-designed test rig for single-span rotor system. The rotor shaft vibration responses were measured in the processes of both stable and speed up-down running. When the oil-film is oscillating, in the time-domain the rotor vibration is featured with complex multi-period and the center routes of rotor shaft are all of irregularly diffused curves. The sub-frequency, i.e. , 0.44 times the frequency, is shown obviously in both the power-density and holographic spectra. An analysis of time-frequency domain when the rotor running up and down, as indicated by 3-D frequency spectrogram and time-frequency indexing chart, revealed the progress how a rotor oil-film changes from whirling to oscillating state. Results of the experiment and analysis are of importance to further study on the faults due to oil-film instability and the implementation of monitoring and predicting of rotating machines.