An analytical model for open-ended squeeze film damper with a circumferential central groove

In this paper, the effect of a circumferential central groove on an open-ended squeeze film damper is analytically investigated. Flow equations in both the central groove and film land are solved by applying the technique of separation of variables. Model validation is presented by a rotor-squeeze film damper test rig using a recorded squeeze film damper film pressure, where a significant improvement from a classical squeeze film damper model is shown. It is found that the central groove has a high and stable pressure region while neglecting the groove effect that would over-estimate the damping force. Both simulation and experiment show that the increase of supply flow escalates the damper pressure and it could possibly avoid the film cavitation, thus raising the squeeze film damper reaction force. In addition, the effects of different groove cross-section shapes including rectangle, square, semi-circle, and semi-ellipse are evaluated. Model sensitivity shows that the size of the central groove has more impact on the damper performance than the shape of the groove.