Tribological Assessment of Porous Kozeny Carman Short Bearings Under Viscosity Variation and Elastic Roughness Deformation

Abstract

This study presents a comprehensive analysis of a porous, rough, elastic short bearing operating under ferrohydrodynamic lubrication with viscosity variation. Rosensweig’s viscosity formulation is incorporated to represent magnetoviscous effects, while the Neuringer–Rosensweig model governs magnetic fluid flow in a porous medium. A stochastic averaged modified Reynolds equation is developed to capture the combined influences of porosity, deformable surface roughness, viscosity variation, and elastic deformation. Numerical solutions are obtained using a finite-difference approach to evaluate the pressure profile and corresponding load carrying capacity (LCC).

The results reveal that elastic deformation, porosity, and positively skewed roughness significantly reduce LCC, whereas transverse and negatively skewed roughness textures enhance performance. Viscosity variation and magnetization can partially counteract performance losses when deformation is small and the bearing aspect ratio is optimally chosen. The study highlights the complex interplay between microstructural porosity, surface topology, and magnetoviscous effects, offering design insights for optimizing advanced ferrofluid-lubricated bearing systems.