转子/密封系统失稳振动抑制的动力吸振方法研究

Dynamic vibration absorber based instability vibration suppression of a rotor/seal system

针对密封中流体引起转子/密封系统振动失稳的问题。提出采用动力吸振器(DVA)实现转子/密封系统失稳振动抑制。建立转子/密封-DVA系统非线性微分方程,采用数值方法求解并获得附加DVA前后转子/密封系统的非线性特性;根据Hurwitz判据获得系统的临界稳定条件;通过遗传算法优化DVA参数,获得附加优化DVA前后转子/密封系统稳定性。结果表明:附加DVA能够改变转子/密封系统失稳振动频率和失稳阈值;在一定的转速范围内失稳振动被完全抑制;在不完全抑制的转速范围内,附加DVA能降低失稳振动的振幅。

The dynamic vibration absorber(DVA) was proposed to suppress the instability vibration of a rotor/seal system. A model for the rotor/seal system with DVA was established. A numerical method was utilized to obtain the nonlinear characteristics of the rotor/seal system without and with DVA. The critical stability condition was obtained by the Routh-Hurwitz criterion. Then the genetic algorithm was applied to optimize the DVA parameters, and the stability was discussed. The results show that the DVA is effective to change the instability vibration frequency and threshold of the rotor/seal system. The instability vibration can be completely suppressed within a certain range of rotating speed. The DVA can reduce the amplitude of the instability vibration in some range of rotating speed, at which the instability vibration is partially suppressed.