某滑动轴承-转子系统次同步失稳机理分析及试验研究

Analysis and experimental research on sub-synchronous destabilization mechanism of rotor system in a sliding bearing

通过简化的轴承转子系统模型,分析了次同步失稳机理,给出了次同步失稳解决方案。在试验台架上进行了5叶可倾瓦滑动轴承支承的柔性转子系统运转试验,当工作转速处于2和3阶临界转速之间时,观察到了明显的次同步失稳现象,获得了失稳门槛转速,分析得出轴承中环形流体周向平均速度系数。通过修改转子结构,提高低阶横向弯曲临界转速,有效消除了次同步失稳,实现了试验转子的超高速稳定运行。

The sub-synchronous destabilization mechanisms of rotor system in a sliding bearing have been investigated according to a simplified model of beating rotor system. A destabilization solution method is also proposed. A running test of a flexible sliding bearing rotor system with 5 tilting-pads was conducted on the rotor experiment platform. During the test, an obvious sub-synchronous destabilization was occurred when the operating speed rose from the 2nd to the 3rd critical speed. The threshold speed of destabilization was obtained. By analyzing the experimental results, the average circumferential velocity of the circular fluid in the bearing was derived. By modifying the rotor configuration, the lower critical speed of lateral bending has been raised, and the destabilization has been eliminated. The steady ultrahigh-speed operating of the new test rotor was carried out.