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

摘要

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.