Inner Race Dynamics of a High-Speed Ball Bearing With Elastic Ring Squeeze Film Damper

Abstract

This paper aims at the inner race dynamics of a high-speed ball bearing incorporated with Elastic Ring Squeeze Film Damper (ERSFD). A dynamic model of the inner race with three degrees-of-freedom (DOFs) is established in an ERSFD-integrated ball bearing. The ball contact force and operating contact angle are characterized using an improved quasi-static model, which includes the motion of the outer race when establishing the geometric relationship between bearing displacement and contact elastic deformation. Numerical simulations were performed for bearings with or without ERSFD. The model was validated using Campbell diagram and measured displacement response and center trajectory of the inner race at different rotor speeds. The results show that the ERSFD provides adequate stable traction on the ball and limits excessive increase in the inner race contact angle. Such load-carrying condition benefits for decrease in ball orbital revolution skid at high rotor speeds. The ERSFD enables rotor's unbalance force to dominate bearing motion, resulting in stable periodic motion of the inner race at high rotor speeds. For ball bearings without ERSFD, the inner race possesses stable motion at low and moderate rotor speeds, but is more prone to instability at high rotor speeds.