Nonlinear vibration characteristics of a marine turbocharger rotor system

Aiming at the rotor dynamic problem of one self-designed marine turbocharger, considering the nonlinear oil-film force effect, a finite element model rotor-bearing system was established. The rotor systems critical speed, nonlinear vibration spectrum and shaft cener's orbits were obtained with numerical simulation. Through comparatively analyzing vibration characteristics caused by the nonlinear oil film force and unbalance, the nonlinear dynamic behaviors of the turbocharger rotor-bearing system were studied to explore the main causes of the rotor system vibration. The influences of the inlet lubricating oil temperature and bearing clearance on the system vibration were investigated and the structure design and optimization methods were proposed to reduce the vibration of the turbocharger rotor system.