This paper presents the exploration for improving the static and dynamic performance behaviours of a self-acting rigid gas journal bearing employing some new conceived micro-depth pocketed surface topographies at the bore. The conceived micro-pockets comprise of relatively large size rectangular pocket having micro-depth at bearing bore in the converging zone followed by placing of different designs of sub-pockets at the trailing edge of the previous one in the direction of journal rotation. The form of equation achieved from Patir and Cheng’s model for the case of hydrodynamic lubrication regime and the related dynamic pressure equations have been solved using the finite volume method discretisation scheme followed by the solution of the algebraic equations using the Gauss-Seidel iterative method. The minimum film thickness, frictional force, side leakage, bearing dynamic coefficients, effective stiffness, effective damping, and critical mass parameters have been investigated with each new bore surface topography and compared with the performances of conventional aerodynamic journal bearing. Substantial improvements in both static and dynamic performances have been found with the new micro-pocketed bore surface topographies as compared to conventional one. Moreover, the established best bore design has produced significant increase (21%) in minimum film thickness, substantial reduction (12%) in coefficient of friction, and excellent improvement (170%) in the stability parameter (critical mass) as compared to the conventional case.

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This article investigates the static and dynamic performances of bionic-textures fused micro-pocketed journal bearing considering cavitation. The new bionic textures placed inside the micro-pocket towards the trailing side has been conceived inspired from the skins of freshwater fish. The mass conservation satisfying partial differential lubrication equations for the static and dynamic pressures are discretized using finite volume method (FVM) followed by simultaneous solution of the system equations using the Fischer-Burmeister-Newton-Schur (FBNS) and the Broyden's method with Sherman-Morrison formula. The minimum film thickness, friction force, temperature rise, dynamic coefficients, effective damping and stiffness, critical mass and system characteristic roots have been explored with new conceived bores and the numerical results have also been compared with conventional plain and conventional pocketed bore bearings. Significant static and dynamic performance improvements have been found in presence of bionic textures fused micro-pocketed bores in comparison to conventional bores.