Influence of microdimple on lubrication performance of textured plunger pump

Purpose - The purpose of this study is to investigate the influence of dimple radius, depth and density on the lubrication performance of the plunger. Design/methodology/approach - A lubrication model was adopted to consider eccentricity and deformation during the working process of the plunger, and a rig test was performed to confirm the simulation results. The texture was fabricated using laser surface texturing. Findings - The simulation results suggested that when dimple radius or depth increases, oil film thickness of the plunger increases before decreasing, and asperity friction displays an opposite trend. Therefore, appropriate microdimple texture could facilitate lubrication performance improvement and reduce the wear. Microdimples were then lased on the plunger surface, and a basic tribological test was conducted to validate the simulation results. The experimental results suggested that the average friction coefficient decreased from 0.18 to 0.13, a reduction of 27.8%. Social implications - The introduction of microdimple on a plunger couple to reduce friction and improve lubrication is expected to provide a new approach to developing high-performance plunger couple and improve the performance of the internal combustion engine. If applied, the surface texture could help reduce friction by around 27% and cap the cost relative to the plugger friction. Originality/value - The microdimple texture was introduced into the plunger couple of a vehicle to reduce the friction and improve the performance. Findings suggested that surface texture could be used in the automotive industry to improve oil efficiency and lubrication performance. Peer review - The peer review history for this article is available at: http://dx.doi.org/10.1108/ILT-07-2020-0259.