外阻尼对滑动轴承转子系统稳定性的作用

在线性范围内对滑动轴承转子系统在转子外阻尼作用下的稳定性区域形态进行了研究，并分别导出了立式和卧式转子系统的界限转速及涡动频率的解析表达式。结果表明，外阻尼可使立式系统在某一界限转速外进入无上限稳定区；而使卧式系统出现了两个界限转速，形成一个失稳区夹于两个稳定区之间的关系稳定性区域形态，最后通过算例对有关推论进行了证明。

Effect of External Damping on the Stability of an Oil Film Bearing-Rotor System

On the basis of linear assumption, the study on the regional pattern of the stability for an oil film bearing-rotor system with extemal rotor damping is conducted. The analytical expressions of the threshold speed and whirling frequency of rotor both for the vertical and horizontal systems are obtained. The results show that the external damping can make the vertical system enter an upper-limit -free stable region at a certain threshold speed and produce two threshold speeds for the horizontal system , evolving a regional pattern of the stability where one unstable region is sandwiched between two stable ones. The results conducted are proved by a following example calculation.