Numerical Model for Determining the Dynamic Parameters of Gas Journal Bearings With Deformable Porous Media

Abstract Porous gas bearings for industrial applications need higher load capacities and supply pressures in the lubricating gas film. Due to the porous medium having a relatively low elastic modulus, it is necessary to consider the deformation caused by the pressure surface; this is the fluid-structure interaction of the lubricant and porous media. Although the elastic deformation of the porous media is in the order of micrometers, the clearance dimension is in that order of magnitude. Any slight change in the dimension of the clearance has a significant effect on the behavior of the porous gas bearing. This work develops an algorithm based on the finite difference method (FDM) (to solve the lubricant fluid film) and analytical (to solve the porous media deformation) for predicting the dynamic behavior of the porous gas journal bearing (PGJB). The paper analyzes the effect of the variations of the porous medium elastic modulus, the supply pressure, and the porous media thickness variation on the dynamic behavior of the porous gas journal bearing: direct and cross-coupled stiffness coefficient and direct and cross-coupled damping coefficient. The work also compares results with published literature.