Squeeze film between porous rough elliptical plates

Abstract

This paper concerns the study of the effect of surface roughness on the performance of the squeeze film formed when the upper plate with a porous facing approached an impermeable and flat lower plate. The bearing surfaces are assumed to be transversely rough. The roughness of the bearing surface is described by a stochastic random variable with non zero mean, variance and skew ness. The associated Reynolds’ equation is solved with appropriate boundary conditions. Results for bearing performance characteristics such as load carrying capacity and response time for different values of mean, standard deviation and measure of symmetry are numerically computed and the same are presented graphically as well as in tabular form. It is observed that more or less the bearing suffers because of transverse surface roughness. However, negatively skewed roughness may enhance the performance of the bearing system for suitable choices of variance. Further, the performance of the bearing system registers a steady improvement with the increasing values of the aspect ratio. Even the negative variance may lead to a better performance. In addition, the response time adopts the trends of the load carrying capacity. This article reveals that the aspect ratio has a strong effect on the performance of the bearing system. The investigation conducted in this article suggests that the roughness must be accounted for while designing the bearing system even though there is the occurrence of a suitable aspect ratio.

Key words: Reynolds equation, random roughness, squeeze film, pressure, load carrying capacity