Performance of hydrodynamic textured journal bearing with the combined influence of elastic deformation and pseudo-plastic lubricant

Abstract

This study outlines the performances of finite-length journal bearing with textured liner, shear-thinning Rabinowitsch lubricants, and considers the elastic deformation of the bearing liner. The yielded nonlinear Rabinowitsch-Reynolds PDE system has been solved using the finite difference method combined with Elrod’s algorithm for the case of cylindrical textures. The static performance of hydrodynamic lubrication, in this case, involves different parameters such as depth of texture, eccentricity ratio, elastic deformation factor, rheological index, etc. Results showed that, at a fixed eccentricity ratio, texturing of the bearing’s converging area enhances significantly the load-carrying capacity and reduces the friction coefficient compared to the smooth bearing surface (up to $22\mathrm{\%}$ in load capacity and $17\mathrm{\%}$ in friction coefficient). On the other hand, using a lubricant with more pronounced shear-thinning behavior and/or elastic liner reduces the journal bearing performances (up to $25\mathrm{\%}$ in load capacity and $30\mathrm{\%}$ in pressure). By applying the optimization technique (particle swarm optimization), an optimal arrangement of textures that can compensate for these losses in performance even at high eccentricity has been found. This optimal texture with dimensionless dimple’s depth set to 1 $(r_y=40\mu \mathrm{m})$ improves the load capacity with $10\mathrm{\%}$ for a lubricant with a rheological index $\overline{\alpha }=0.6$ and elastic bearing liner with deformation parameter $C_0=0.05$ .