Nonlinear vibration of rotor systems caused by assembly process of a bearing outer ring of an aero-engine

According to the assembly process parameters features of turbine supports of an aero-engine, the vibration characteristics in a rotor system with different assembly process parameters between an outer ring of the bearing and a casing were carried out experimentally. The parameters of assembly process of a bearing outer ring were interference fit, clearance fit and transition fit. The influence on the fit of bearing outer ring and vibration of the rotor caused by casing temperature field and outer ring tinghtening torque were also carried out. The results show that: when assembly process of a bearing outer ring is clearance fit, subharmonic, super-subharmonic frequencys, nonlinear resonances occur and outer ring tightening torque in increases is one of the main factors that suppress rotor vibration. Assembly relationship of bearing out ring from the transition to the clearence occurs which is caused by temperature field of the casing.