An Analytical and Experimental Investigation of Turbulent Flow in Bearing Films Including Convective Fluid Inertia Forces

Abstract

A means of handling both fluid film turbulence and the effects of fluid convective inertia in bearing films has been developed. The analysis employs a number of simplifying assumptions but has proved quite successful in the prediction of experimentally measured pressures. In this analysis turbulence is treated by means of turbulent viscosity correction factors. Convective inertia is accounted for by convective derivatives of mean fluid velocities averaged over the bearing film. Direct numerical solution of simultaneous equations representing conservation of momentum and fluid continuity is employed. The analysis developed is applied to pad bearings of arbitrary surface geometry, and has been incorporated in a computer program to calculate the film pressures developed in such bearings. Results from this program are compared with experimental pressure profile measurements made on a 12-in. dia, four pad, shrouded step journal bearing with silicone fluids as test lubricants. Good agreement is obtained for both concentric and eccentric operation.