EFFECT OF A CIRCUMFERENTIAL FEEDING GROOVE ON THE DYNAMIC FORCE RESPONSE OF A SHORT SQUEEZE FILM DAMPER

The effect of a circumferential feeding groove on the dynamic force re sponse of a short length, open end squeeze film damper is studied expe rimentally. Damper configurations with increasing groove depths and jo urnal orbit radii were tested for several conditions of whirl frequenc y and lubricant viscosity. Significant levels of dynamic pressure were measured at the circumferential groove, and relatively large tangenti al (damping) forces are produced at the groove which contribute consid erably to the damping characteristics of the SFD test articles. Radial forces of substantial magnitude are determined at the groove and at t he thin film land where the squeeze film Reynolds number is typically less than 1. The circumferential groove is thought to induce an inerti a like effect into the film land. The experimental results correlate w ell with the predictions from a groove volume-circumferential flow mod el developed.