422 / 2022-07-31 22:15:42

Nonlinear vibration of rotor system with dynamic angular misalignment of ball bearing

Dynamic misalignment; Ball bearing-rotor system; Nonlinear vibration; Bifurcation

Aiming at the nonlinear vibration problem caused by dynamic misalignment of rolling bearings in the rotor system, a rotor dynamic model with dynamic misalignment of rolling bearings is established, and the effects of the dynamic misalignment of single and two bearings and the phase relationship of two dynamic misalignment bearings on the vibration characteristics of the rotor system are studied. The effects of bearing clearance, raceway curvature radius coefficient and the number of balls on the nonlinear vibration response of dynamically misaligned bearing-unbalanced rotor system are further analysed. The results show that the dynamic misalignment of the bearing can excite the rotor vibration by double rotating frequency, and lead to the increase of the rotor resonance speed and the enhancement of the hardening-type nonlinearity characteristics of the system. The influence of dynamic misalignment of two bearings with opposite phase on rotor resonance is greater than that of the same phase. The stability of the system can be improved by decreasing the bearing clearance and increasing the curvature radius coefficient. Increasing the number of balls leads to the increase of resonance peak and the enhancement of hardening-type nonlinearity characteristics. The results can provide some basis for dynamic design, health monitoring and fault diagnosis of bearing-rotor system.