气体润滑轴承-转子系统非线性动力学特征的实验

对高速气体润滑轴承转子系统进行了稳定性试验研究.通过轴心轨迹、频率耦合三维图、频谱和分叉图,分析了系统非线性行为特征.实验证明气体润滑轴承-转子系统中的气膜涡动是系统非线性失稳的主要原因,气膜涡动导致的倍周期分叉是系统进入混沌振动的必由途径.通过调整系统固有频率和气膜润滑涡动频率之间的耦合关系,使得失稳转速远离设计转速;以及利用试验中所证实的混沌"有界"性质,有效的控制振幅,将是提高转子-轴承系统非线性稳定性的新途径. 

Experimental research on nonlinear dynamic characteristic of gas lubrication bearings and high speed rotors

A stability experiment on high speed rotor and gas lubrication bearings was presented in this paper.Based on shaft center orbits,frequency coupling 3-D plot,frequency spectrum and bifurcation plot,the nonlinear characteristics of rotor bearing system were analyzed.The experiment proved that,gas whirl in gas bearing and rotor system was a major contributing factor to nonlinear instability.Double periodic bifurcation caused by gas whirl was an inevitable path to chaos vibration.The instability rotational speed will vary a lot from design speed by modulation of the coupling relationship between system's inherent frequency and gas whirl frequency,meanwhile effective control of chaos vibration based on bounded ness of chaos is a new method to improve nonlinear stability of rotor and bearings.