Elastohydrostatic Lubrication of Circular Plate Thrust Bearings

Abstract

The subject of elastohydrodynamic lubrication has developed considerably in recent years and in the present paper the influence of elastic distortion upon the performance of a hydrostatic thrust bearing is considered. A circular plate hydrostatic thrust bearing is considered and one of the pads is assumed to be lined by a thin layer of elastic material. A simplified approach to the calculation of elastic displacements is used and an approximate analytical solution of the governing elastohydrostatic equations is presented. Theoretical solutions showing the influence of elastic distortion upon pressure distribution are presented. Experimental measurements of radial pressure distribution are recorded for bearings lined with low modulus nitrile and polyurethane rubber. Difficulties encountered in the measurement of the rubber properties prevented a strict comparison between experimental and theoretical results but the selection of an equivalent modulus enabled qualitative agreement to be demonstrated. Elastohydrostatic behavior is shown to have a beneficial effect upon bearing performance.