Combined effects of elastic deformation and piezo-viscous dependency on the performance of a journal bearing operating with a non-Newtonian fluid
Boualem Chetti, Mohamed Hemis, Othman Tahar, Moussa Smara
Abstract
A theoretical study of the effects of elastic deformation and the variation of viscosity with pressure on the performance characteristics of a circular journal bearing lubricated with non-Newtonian fluids. The Barus law and the power law model are used to express the viscosity-pressure variation and the non-Newtonian behavior of fluids respectively. To determine the displacement field at the fluid film bearing liner interface, the elastic thin liner model is used. The modified Reynolds equation accounting the viscosity pressure dependency in the non-Newtonian fluids is mathematically derived and solved using finite difference method, to obtain the fluid film pressure field. The static performance characteristics for finite-width journal bearing are evaluated for various values of pressure-viscosity coefficient, the power law index n, and the elastic deformation coefficient. According to the results obtained, it is found that the hydrodynamic pressure and non-dimensional load-carrying capacity increase as the power law index and pressure-viscosity coefficient increases especially for rigid and heavily loaded bearing case. In addition, the combined effects of the elastic deformation and the viscosity pressure dependency are found to be more pronounced on the performance characteristics of a heavily loaded journal bearing operating with a shear-thickening fluid.