Calculation of Operational Parameter Variation of Finite Slider and Journal Bearings With Stochastic Roughness on the Stator and the Rotor

Abstract

Within the framework of stochastic surface roughness representation, a recently derived Reynolds-type equation has been employed by the authors to compute the average values of a bearing’s operational parameters. To enhance the understanding of hydrodynamic lubrication phenomena in rough bearings, it is necessary to account for the stochastic nature of these parameters by evaluating their higher-order moments, such as variance. This study aims to derive and quantify equations for the computation of these higher-order moments. Specifically, the article presents equations for the variance of key operational parameters, including pressure, load carrying capacity, friction force, and friction coefficient, in both finite width slider and journal bearings. Furthermore, Raimondi-Boyd-like charts are developed for various L/B and L/D ratios, across a wide range of stator and rotor roughness standard deviations, applicable to both bearing types.