Nonlinear response of rotor system with bearing dynamic misalignment

Aiming at the nonlinear vibration problem caused by the dynamic misalignment of rolling bearings in the rotating machinery, a rotor dynamic model with bearing dynamic misalignment 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 rotor vibration characteristics are researched. The effects of bearing clearance, raceway curvature radius, the ball number and radial load on the nonlinear vibration response of the dynamic misalignment bearing-unbalance rotor system are further analyzed. The results show that the dynamic misalignment of the bearing can excite the vibration at twice the rotor frequency, raise the resonance speed and enhance the hardening-type nonlinearity characteristics of the rotor. The influence of dynamic misalignment under two bearings with out-of-phase on rotor resonance is greater than that of the in-phase. The stability of the system can be improved by decreasing the bearing clearance and increasing the curvature radius coefficient. The vibration caused by bearing dynamic misalignment can be reduced by selecting the bearing with more balls and appropriately increasing the bearing load.

Automated summary

A rotor dynamic model with bearing dynamic misalignment is established to study the nonlinear vibration problem caused by the dynamic misalignment of rolling bearings in rotating machinery. The effects of single and two bearings' dynamic misalignment and the phase relationship of two dynamic misalignment bearings on the rotor vibration characteristics are investigated. Furthermore, the influence of bearing clearance, raceway curvature radius, ball number, and radial load on the nonlinear vibration response of the dynamic misalignment bearing-unbalance rotor system is analyzed. The results indicate that dynamic misalignment can excite vibration at twice the rotor frequency, increase resonance speed, and enhance the rotor's hardening-type nonlinearity characteristics. The influence of out-of-phase dynamic misalignment on rotor resonance is greater than that of in-phase misalignment. The system stability can be improved by reducing bearing clearance and increasing the curvature radius coefficient. The vibration caused by bearing dynamic misalignment can be reduced by selecting bearings with more balls and appropriately increasing the bearing load.