Impact Dynamics of High Speed Rotors in Retainer Bearings and Measurement Concepts

This paper presents results on the impact dynamics of a high speed rigid rotor in a simple rigid retainer bearing with small clearance. The contact between the rotor and the bearing is modelled with the Coulomb-friction law and the coefficient of restitu..tion. To measure the contact force and the contact time during the impact, we have developed a force sensing device based on Hertz Impact Theory. Analysis shows that a small air-gap is an important parameter, which influences to the whirling motion of the rotor around the bearing.