径向动静压浮环轴承-转子系统稳定性分析

Stability analysis of a journal floating ring hybrid bearing-rotor system

以径向动静压浮环轴承-转子系统为研究对象,计入浮环质量和转子刚度建立了统一的动力学方程,用Routh-Hurwitz准则推导了单质量弹性对称系统的稳定性判据。用有限差分计算了某高速径向动静压浮环轴承的刚度系数和阻尼系数,在此基础上得到了不同浮环质量和转子刚度下动静压浮环轴承-转子系统的稳定性曲线。计算结果表明,浮环质量对系统稳定性影响不大,而随着转子刚度减小,系统失稳转速迅速降低。该文在高速浮环轴承-弹性转子稳定性整体建模和分析方面有较大的参考意义。

A unitized dynamic model for a journal floating ring hybrid bearing-rotor system was established considering floating ring mass and rotor stiffness. The stability criterion for the journal floating ring hybrid bearing-rotor system was derived using Routh-Hurwitz method. The dynamic characteristic coefficients of inner and outer films for a high speed floating ring bearing were calculated with the finite difference method under different operation conditions. Further more the variation of the threshold rotating speed of the bearing-rotor system with floating ring mass and rotor stiffness was acquired. The results showed that the threshold rotating speed of the bearing-rotor system decreases slightly with increase in floating ring mass under different eccentricities; at the same time, the threshold rotating speed of the bearing-rotor system increases quickly with increase in rotor stiffness. The results provided a reference for the overall modeling and stability analysis of floating ring hybrid bearing-elastic rotor systems.