Investigation on the Influence of Earthworm Surface Texture on the Lubrication Performance of Hydrostatic Thrust Bearing

ABSTRACT The purpose of this study is to investigate the influence of earthworm surface texture on the lubrication performance of hydrostatic thrust bearings. The lubrication performance is evaluated based on the oil film load‐carrying capacity and oil film temperature field under normal, high‐speed, and heavy‐load conditions. The semicylindrical texture mimicking the earthworm's unique surface structure was applied to the oil sealing edge of hydrostatic thrust bearings. Numerical simulations were conducted to systematically analyze the effects of texture position, number, and depth on the oil film temperature and pressure fields under normal, high‐speed, and heavy‐load conditions. The earthworm textures effectively improved the load‐carrying capacity of the hydrostatic thrust bearing oil film, while exerting a negligible effect on the oil film temperature field. The optimal lubrication performance was achieved when the textures were arranged at Position 2 on the countercurrent side of the inner cavity oil sealing edge, with 9 textures and a depth of 3 mm. The maximum discrepancy between simulation results and experimental findings was 3%, confirming the accuracy of the numerical method. This study demonstrates the effectiveness of earthworm surface textures in improving hydrostatic thrust bearing performance and provides valuable theoretical guidance for practical engineering applications.