Study on Piston Skirt Lubrication by Means of Oil Film Visualization

- Relation between Surface Characteristic, Oil Film Thickness and Friction -

Abstract

Optimization of piston skirt surface characteristic is effective for realizing piston friction reduction of internal combustion engine. It is important to know the effects of surface roughness of piston skirt on the friction and the oil film thickness. In this study, based on the result of friction measurement by floating liner engine, the oil film thickness is visualized and observed in a sapphire cylinder engine using laser induced fluorescence (LIF) method on the piston skirt with three kinds of surface roughness. As a result, it is found that skirt roughness affects oil film thickness and lubrication conditions.