Nonlinear Vibration Response Analysis of Intermediate Bearing-Dual Rotor-Bearing System

In order to study the nonlinear vibration response characteristics of aero-engine rotor operation, a mechanical analysis model of a dual-rotor system supported by rolling bearings is constructed. The two ends of the model are supported by rolling bearings, and the high-pressure rotors and low-pressure rotors are coupled by intermediate bearings. The dynamic response of the systme under different intermediate bearing clearances is described by using the spectrogram and axis track diagram. Moreover, phase diagram, poincare section and and bifurcation diagram are employed to elucidate the complex dynamic phtnomena like period, quasi-period and chaos in the evolution of nonlinear dynamic state. The results show that as the intermediary bearing clearance becomes larger, the system vibration frequency becomes rich, and the amplitude change of the rotor system in the vertical direction is larger than that in the horizontal direction, the speed interval of the two-rotor system in the chaotic state becomes larger, which seriously affects the stability of the system operation. The research results provide a certain theoretical reference for system optimization design, vibration control and failure prevention.