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.