Stability of periodic motion on two-span rotor-bearing system with coupling faults of pedestal looseness and crack

摘要

A dynamic model was set up for the two-span rotor-bearing system with coupling faults of pedestal looseness and crack. Using the continuation-shooting algorithm for periodic solution of nonlinear non-autonomous system, the stability of the system periodic motion was studied by the Floquet theory. The unstable form of the rotor system with pedestal looseness fault is saddle-node bifurcation, and that with crack fault is period-doubling bifurcation. The main influence to the system with coupling faults is crack, the unstable form is period-doubling bifurcation. The saddle-node bifurcation, hopf bifurcation and period-doubling bifurcation are found in the system with coupling faults. The conclusions provide theoretic basis reference for the failure diagnosis of the rotor-bearing system.