Dynamic Performance of the Stepped Hydrostatic Circumferential Gas Seal

TLDR: Theoretical analysis of dynamic tracking and leakage characteristics of a self-centering, hydrostatic, stepped gas seal is presented in this article, taking into account shaft speed and whirl, pressure ratio across the seal, fluid film properties and face friction effects.

Abstract: Theoretical analysis of dynamic tracking and leakage characteristics of a self-centering, hydrostatic, stepped gas seal is presented. The equations of motion are solved numerically, taking into account shaft speed and whirl, pressure ratio across the seal, fluid film properties and face friction effects. The analysis is limtied to low axial Reynolds numbers and negligible tangential hydrodynamic pressure buildup. Became the model neglects azimuthal pressure gradients, the analyzed seals must be either axially short or limited to small eccentricities. An analytical tracking criterion is established for high pressure ratios for preliminary design purposes. Presented at the 43rd Annual Meeting in Cleveland, Ohio May 9–12, 1988