弹性支承滑动轴承的非线性油膜失稳研究

Research on Nonlinear Film Unstable Vibration of Bearing System Supported by Flexible Support

本文采用非线性分析方法研究了同时考虑支承阻尼和转子外阻尼的弹性支承滑动轴承系统的油膜失稳振动问题.通过计算转子在油膜失稳区的幅频特性,证明了失稳区的宽度和幅度都是有限的.对幅频特性的进一步分析表明:较低的支承刚度和适当的支承阻尼或较大的转子外阻尼可以减小失稳区的宽度和幅度,以致转子可以平稳地超过失稳区而在上稳定区工作.较高的支承阻尼虽然可以降低失稳区的幅度,但可能导致失稳区变宽.

This paper studies the film unstable vibration of bearing system supported by flexible support considering both support damp and rotor extemal damp by use of nonlinear analysis. Amplitude - frequency characteristic of the rotor is calculated in film unstable region, which verifies that the width and the amplitude of the region is limitary. Further analysis of the amplitude - frequency characteristic shows that lower support stiflhess and moderate support damp or higher rotor extemal damp can decrease the width and the amplitude so that the rotor will be able to cross the unstale region to the upper stable region smoothly higher support damp may decrease the amplitude but it properbly leads wider the region.