Analysis of hydrostatic rough thrust bearing lubricated with Rabinowitsch fluid considering fluid inertia in supply region

Abstract

With the advancement of lubrication technology, precise prediction of performance characteristics of bearings is the first and inevitable step for stability of mechanical systems. Most of the existing theoretical analyses of hydrostatic thrust bearings lubricated with non-Newtonian fluids have considered the lubricant inertia, only in the recess and land regions but did not account either for the inertia of lubricant in the supply region or the surface roughness of the bearings. This could be a cause for the deviation between the theoretical results and the experimental data under certain conditions. In this work, combined influence of surface roughness as well as lubricant inertia in the supply region, on the static properties of a hydrostatic stepped thrust bearing lubricated with a non-Newtonian fluid, has been discussed using Rabinowitsch fluid model. Surface roughness effects have been accounted for using Christensen theory of rough surfaces. It is expected that the current study could bridge the gap between the experimental and theoretical studies. Solution for momentum equation has been obtained by means of average inertia approach. Analytic expressions for film pressure have been derived for radial and circumferential roughness patterns. Mathematica 11.0 has been used for numerical computations, wherever necessary. Results for film pressure and load carrying capacity have been plotted and discussed. It is observed that the present results are in a better agreement with the experimental data.