Behaviour of hydrodynamic journal bearing under the combined influence of textured surface and Non-Newtonian Rabinowitsch fluid model

Abstract

In the present study, the static characteristics of hydrodynamic circular journal bearings of finite length are highlighted, using the combined influences of textured surface and non-Newtonian lubricants behavior, obeying to the Rabinowitsch fluid model. The associated nonlinear Rabinowitsch-Reynolds equation has been discretized using finite differences scheme and solved by the mean of Elrod’s algorithm taking into account the presence of cylindrical textures on full/optimum bearing surface. Following to the absence of textures on the bearing surface or the non-Newtonian fluid behavior, the obtained results are in good agreement with the reference ones. The hydrodynamic lubrication static performances are computed for various parameters such as textures location; eccentricity ratio and the rheological coeffcient. The results suggest that texturing the bearing’s convergent zone enhances significantly the load carrying capacity and reduces the friction coeffcient, whereas texturing the full bearing surface may leads to bad performances. It is also noticed that the pseudoplastic lubricant coeffcient decreases the bearing performances (load capacity and pressure) compared to Newtonian fluid cases. Considering the optimal arrangement of textures on the contact surface, a significant improvement in terms of load capacity and friction can be achieved, especially at low pseudoplasticity effect.

Keywords

• hydrodynamic journal bearing
• surface texturing
• cavitation effect
• non-newtonian fluid
• rabinowitsch fluid model