In order to reveal the influence of the groove texture pattern on the friction performance of radial journal bearing,a numerical model of oil-air two-phase flow in the cavity of radial journal bearing was established based on the air-liquid two-phase flow theory.The conventional texture was modified into an asymmetric texture with stepped inlet and outlet,the inlet and outlet wall height ratio H was defined as asymmetric factor,the model was solved by SIMPLEC algorithm.The influence of the asymmetrical factors on the flow field in the fluid domain of groove texture element was analyzed,and the influences of asymmetrical factors on tribological properties of journal bearings at different position textures and different rotational speeds were investigated.The results show that the groove texture arrangement at the convergent wedge inlet can effectively improve the tribological properties.The pressure on the upper wall with different H values is greater than that of the symmetric textured condition and the non-textured condition,the reasons are the change of flow velocity,direction and the generation of double vortices at the outlet of the textured pit respectively.With the increase of the rotating speed,the volume fraction of oil phase in the bearing cavity decreases.When H=0.25,the bearing capacity is the highest and the friction coefficient is the minimum.Therefore,it is of great significance to study the asymmetrical surface texture for improving the lubrication effect of radial sliding bearings.