A comprehensive numerical model for double-layered porous air journal bearing at higher bearing numbers

Abstract

Modeling air/gas lubricated double-layered porous journal bearing requires the solution of compressible Reynolds equation. It is observed that at higher bearing numbers, treatment of Reynolds equation with finite difference method using second-order central difference exhibits instabilities due to convective term dominance. To address such instabilities, Reynolds equation is discretized using finite volume and a third-order interpolation scheme to obtain variable values at grid point centers. Multistage Runge–Kutta method and biconjugate gradient stabilized method are used for solving governing equations at film and porous regions, respectively. Steady state and stability characteristics of finite double-layered porous air journal bearings considering Beavers–Joseph velocity slip at porous-film interface are obtained. Numerically stable results are obtained for bearing numbers up to 150 and feeding parameter values ranging from 0.01 to 10.