Nonlinear Dynamic Analysis of Rolling Bearing–Rotor System

Abstract

This study focuses on an unbalanced rotor system supported by rolling bearings. The variable-step Runge–Kutta method is employed to perform numerical integration and obtain the system's dynamic responses. Bifurcation diagrams under different operating conditions are used to analyze the evolution of system behavior as parameters vary. The results indicate that at lower rotational speeds, the system exhibits quasi-periodic motion with small vibration amplitudes, posing minimal impact on operational stability. As the rotational speed increases, the motion becomes more complex, presenting various response forms such as periodic motion, quasi-periodic motion, and chaos, accompanied by larger vibration amplitudes and unstable system operation. These findings can serve as guidance for system operation under different rotational speeds and provide theoretical support for the stable performance of rolling bearing–rotor systems.