A Study on In-situ Observation of the Micro Flow of Lubricant on the Textured Surface

It is known that surface texturing improves the tribological properties under hydrodynamic lubrication. Generally, it is said that the effect of surface texturing under hydrodynamic lubrication is due to the hydrodynamic pressure. It is considered that the occurrence of the hydrodynamic pressure is related to the details of the lubricant flow. However, experimental approach to observe the details of the lubricant flow and the details discussion about the lubricant flow on textured surface are insufficient. In this study, we investigated the lubricant flow on the textured surface under hydrodynamic lubrication by in-situ observation. The observations of the details of the lubricant flow were conducted by use of fluorescent particles. Using the fluorescent particles as the seed, visualization of the details of the lubricant flow near the textured surface was succeeded. In addition, the motion of the particle indicates that the velocity of the lubricant flow decreased inside of the dimple.