Lubrication characteristics of a textured porous sliding bearing

Abstract

This study investigates the lubrication characteristics of a textured bearing sliding on a porous layer. To properly implement the porous layer effect in the bearing, the Brinkman-extended-Darcy model is employed, which results in a modified Reynolds equation. This equation is then evaluated to examine the effects of the porous layer's material and geometric properties on the lubrication characteristics through the use of (semi-) analytic and numerical approaches. The cavitation effect is reflected in the numerical treatment of the model equation, and an adaptive finite difference scheme is employed to efficiently model the bearing system with finite dimples that may be far smaller than the overall bearing dimensions. Along with the variation trends of the bearing performance with respect to the material and geometric properties of the porous layer, the pattern effects of textured surfaces on the bearing performance indices (load capacity and equivalent friction coefficient) are also thoroughly investigated. Here, the pattern comprised a set of regularly spaced identical dimples either in semi-spherical or semi-ellipsoidal shape, and the effects of size and orientation of the dimples are comprehensively explored to separately identify their influence on the bearing performance indices.