The effect of microstructure surface quality on the oil film load-bearing performance of radial sliding bearings

The study investigates the influence of surface morphology and surface quality of sliding bearings on the dynamic pressure lubrication load-bearing performance of the rotor-bearing system. Taking the hydrodynamic lubrication performance of micro textured journal bearings as the research object, a numerical model of hydrodynamic lubrication of smooth bearings was established. The oil film pressure distribution and static characteristics of bearings were obtained. The results were highly consistent with the classical conclusions. The hydrodynamic lubrication model of radial bearing considering the micro-texture and surface morphology of bearing bush was constructed. The surface morphology of rotor-bearing was constructed by autocorrelation function. The Reynolds equation of hydrodynamic pressure considering the micro-texture surface morphology of bearing bush was solved by finite difference method. The results showed that the pressure and bearing performance of sliding bearing with micro convex were significantly higher than those of smooth bearing, and augmented with the increase of texture height and arrangement density. The load-bearing performance of rotor bearing system was also enhanced with the increase of surface roughness of rotor bearing. However, excessively increasing roughness could disrupt the axial continuity of the original rotor bearing oil film, leading to a decrease in the bearing performance of the rotor bearing system. The developed hydrodynamic lubrication model, which considers the microstructure surface topography of load-bearing performance of radial sliding bearings, provides a theoretical basis for determining the texture size and surface machining quality requirements for sliding bearings.