Theoretical investigation on porous tilting pad bearings considering tilting pad motion and porous material restriction

Porous tilting pad bearings (PTPBs) hold potential for applications that require high bearing stiffness and good stability. This study presents a numerical analysis of PTPBs. A three-dimensional Darcy's equation is coupling solved with the motion equation of tilting pads to establish the air pressure field among the porous materials and gas film. The static performance solved by finite difference method and the dynamic characteristics obtained from perturbation equations are presented for various design parameters, such as bearing clearance, supply pressure, tilting, and radial stiffness. Predictions generally agree with the published load capacity. The coupling mechanism of hydrostatic and hydrodynamic effects in gas film are investigated. The predictions show that PTPB performance is determined by externally pressurized gas and shaft rotation.