A 3D Conservative Model for Self-Lubricated Porous Journal Bearings in a Hydrodynamic Steady State

Successive steps in constructing a realistic conservative 3D model for hydrodynamic porous bearings are presented. They consist in iterative comparisons between theoretical results and industrial knowledge. This model is based on Darcy's law for the porous bearing and an adaptation of Elrod's model to a generalized Reynolds's equation for the flow in the gap between the shaft and the bearing. Capillary effects at the outer surface of the bearing, and pore obstruction at its inner surface, leading to loss of permeability in the region where film thickness is minimal, are highlighted as phenomena which can prevent bearing leakage. They have been taken into account in the boundary conditions of the proposed model.