Analysis of Whirl Instability in Externally Pressurized Gas Bearings with Circular Slots of Tangential Supply

Abstract

This paper describes an analysis of whirl instability in externally pressurized gas bearings with circular slots of tangential supply. to evaluate the inertia effect of the supplied gas on the aerodynamic film force properly, the modified Reynolds equations including inertia forces are used as the governing equations, and reasonable boundary conditions for them are presented anew. They are solved analytically under some simplifications, and the whirl onset speed is calculated for a typical design, considering the effect of turbulence in the film flow and the centrifugal growth of the journal radius. The result is compared with a tested one, and good correspondence is revealed between them.