Research on vibration performance of the nonlinear combined support-flexible rotor system

A finite element model of the cantilever combined support rotor included two discs established in this paper to predict and explain the nonlinear vibration phenomenon. The model considered local nonlinear support force generated by the combined support and the coupling effects of the rotor with the combined support. The nonlinear factors contained the clearance, the Hertz contact force and the vibration of the rolling bearing and the nonlinear force of the squeeze film damper. The combined support included bearing, squeeze film damper and squirrel cage elastic support. Finally, the high-dimensional partial differential equations with local nonlinearity were derived and solved by Newmark-beta combined with Runge-Kutta method. Based on the above theoretical results, the bifurcation phenomenon of vibration response at different positions was analysed and the dynamic response of the rotor system at different positions due to the rotational speed was compared.