三轴承支撑不平衡转子非线性动力学研究

Nonlinear Dynamics of an Unbalanced Rotor Flexible Mounted on Three Journal Bearings

针对具有三个滑动轴承支撑的双跨弹性转子的非线性特点 ,建立了数学模型 ,用数值积分和庞加莱映射方法对采用短轴承模型的该类转子系统动力学特性随某一参数变化时稳定性的改变进行了分析 ,计算结果表明 ,系统具有发生倍周期分叉、概周期的可能。用数值方法得到系统在某些参数域中的分叉图 ,直观显示了系统在某些参数域中的运行状态和轴承几何参数变化对系统动力特性的影响 ,数值分析结果为该类转子 -轴承系统的设计和运行状态控制提供了理论参考。

A mathematical model of a flexible rotor of double disks supported on three plain journal bearings was established as focusing particularly on its nonlinear aspects. The stability of a system with short-bearing model is studied by numerical integral method changing some of the system parameters. The results of calculation show that the system may undergo period doubling bifurcation, quasi-periodic motions. In some typical parameter regions the bifurcation diagrams of the system are acquired with numerical integral method illustrating some states of motion of the system. The quasi-periodic motion may disappear by changing some parameters. The analytic results in this paper provide the theoretical reference for design and operation safety of the system.