Abstract:The rotating parabolic micro-pit were prepared in the cylinder surface. The rotating parabolic micro-pits-liner-piston ring system was studied based on the classic Reynolds equation and the micro-pits dynamic pressure distribution function was established. The impact of micro-pits depth and radius on the lubricating properties of the rotating parabolic micro-pit was analyzed by using Matlab software. The results show that, along with the increasing of micro-pit depth and pit radius, the average film bearing capacity is increased at first then decreased, the average shear stress is gradually decreased and tends to be a stable value. It is because the wedge effect, cavitation in the micro-pit area leads to the fluctuations of average oil film bearing capacity and average shear stress during the movement process of the piston relative to the cylinder liner. The optimization parameters of rotating parabolic micro-pits are achieved.