Nonlinear characteristic investigation of tribo-crack-dynamic rotor system based on full spectrum analysis

Abstract The tribo-crack-dynamic model and experimental method to research dynamic mechanism are proposed based on the full spectrum in this paper. In view of the nonlinear characteristics from rub-impact forces, oil-film forces and time-varying stiffness of crack shaft, the tribo-crack-dynamic rotor model is established to serve the analysis of dynamic mechanism and characteristics. The numerical simulation is developed to obtain the precession signal and bifurcation diagram for the tribo-crack-dynamic rotor system. The results show that the negative frequency components are more abundant and their amplitudes increase in the full spectrum, showing obvious reverse precession characteristics when cracks and rub-impact faults occur at the same time. Experiment investigation on nonlinear dynamics is designed, which verifies the tribo-crack-dynamic model and the positive and negative precession characteristics in multi-fault rotor system.