Effect of rolling bearing parameters on the nonlinear dynamics of offset rotor

Nonlinear vibration of rotating machinery induced by rolling bearings has gradually become a research issue. In many cases, the rotor discs are not always installed in middle of shaft in actual rotor system, and the influence of disc offset on nonlinear vibration needs to be studied in depth as rotating speed increases. This study deals with the effect mechanism of rotor offset on nonlinear dynamic responses. Nonlinear vibration model of offset rotor is established based on finite element method, and the disc offset position along rotor shaft is concerned. The responses are calculated by Newmark-beta integration method, which are also validated by an experimental rig, and the influences of nonlinear parameters of rolling bearings are investigated. The results indicate that disc offset is a crucial factor that can induce more complex nonlinearity coupled with rolling bearing under high-speed conditions.