Texture Shape Optimization for Minimization of Friction Coefficient (Comparison of Shape Optimization Results for Circular and Herringbone Textures)

Abstract

. In order to reduce the friction coefficient of lubricated surfaces with circular and herringbone shaped textures, an adjust variable method was introduced to optimize the shape of the oil film thickness distribution in the textured areas. The optimized oil film thickness distribution can be evolved by the shape updating formula proposed by Sasaoka et al. based on the smoothed sensitivity. For computational convenience, the objective function in the optimization is defined as the friction force, not the friction coefficient. The constraint function was also defined by the Reynolds equation. The finite element method was used in the optimization procedure. The optimization results show that the herringbone shape texture has a bowl-shaped oil film thickness distribution similar to that of the circular shape texture. Furthermore, the location of the deepest part was found to be different.