J1030202 Escapement from a Contacting Vibration of a Rotor System Supported by a Repulsive Magnetic Bearing and contacting with a Backup Bearing

Abstract

A rotor system supported by a repulsive magnetic bearing has a weak damping, and therefore, a contact whirling vibration between the rotor and a backup bearing may occurs when the rotor system passes a critical speed. Four kinds of the contact whirling vibration, a forward sliding type, a backward sliding type, a forward rolling type and a backward rolling type, are possible to occur. It is desired to separate from the contacting condition at the lower rotational speed with smaller amplitude. In this study, the forward sliding contact vibration is considered, and the effective design parameters for early separation from it are investigated analitically. As a result, the larger friction coefficient and the smaller contact stiffness are effective to reduce the rotational speed of separation from the contacting condition.