For looseness-rubbing coupling fault of rotor-bearing system caused by pedestal looseness

the mechanical model and finite element model of dual-disk three-support looseness-rubbing coupling fault of rotor-bearing system were established.The research of effect of rubbing stiffness and looseness stiffness on dynamics characteristics of the system was done with equivalent stiffness model on the loose support

nonlinear finite element method and contact theory.Through the relevant research and analysis

it is found that looseness-rubbing coupling fault mainly is embodied in the rubbing fault.It is also found that high and low peaks appeared alternately in the time-domain graph and the shape of the axis orbit is trapezoid.This feature can be a basis which can diagnose looseness-rubbing coupling fault.