The Effect of Texture Shape on the Load-Carrying Capacity of Gas-Lubricated Parallel Slider Bearings

Surface texturing is used to increase hydrodynamic pressure and reduce friction and wear between gas-lubricated parallel sliding surfaces. The shape, geometry, and density of the patterned microtexture features ("dimples") play a key role in the tribological performance of the textured slider bearings. The objective of this paper is to compare the load-carrying capacity of commonly used dimple shapes for gas-lubricated textured parallel slider bearings. Six different texture shapes are considered, including spherical, ellipsoidal, circular, elliptical, triangular, and chevron-shaped dimples. The pressure distribution and load-carrying capacity generated by different texture shapes are simulated using the compressible Reynolds equation over a domain containing a column of ten dimples. The texture geometry and density are optimized in terms of maximum load-carrying capacity for each individual dimple shape, as a function of operating parameters such as relative velocity and spacing between the two sliding surfaces. The maximum load-carrying capacity of each individual texture shape-with optimized geometry and density-is then compared relative to each other. It is concluded that the ellipsoidal shape results in the highest load-carrying capacity, and the optimal geometry and density are found to be almost independent of the operating conditions.