Nonlinear dynamics of a rotor-ball bearing system with Alford force

The nonlinear dynamic behaviors of an unbalanced rotor system supported on ball bearings with Alford force are investigated. In the rotor model, the rotor unbalance that varied with rotating speed, ball bearing clearance, nonlinear Hertzian contact force, varying compliance vibration, contact angle and Alford force are considered. The bifurcation of the rotor system is analyzed under different operating conditions. It is indicated that the dynamic behavior of the rotor system depends on the rotation speed and ball bearing clearance. The system state trajectory, Poincare maps, frequency spectra and bifurcation diagrams are constructed to analyze the dynamic behavior of the rotor center. Various nonlinear phenomena in the coupled system, such as periodic motion, quasi-periodic motion and chaotic motion are investigated. The study may contribute to a further understanding of the nonlinear dynamics of such a rotor system.