This paper investigates the effects of geometrical features of tailored textures on friction reduction of a surface with a lubricant-film thickness of several to several-tenths micrometers, using the Navier-Stokes equations and the orthogonal experimental design. The results indicate that the surface textured with the selected sawtooth riblets in lubricant can have up to 93.83% less friction than an untextured surface. The thickness of the lubricant film plays the most important role in friction reduction; the height and the ridge angle of the riblets are the secondary factors. The results and principles obtained can potentially be used in the designing of low-friction surfaces in precision machines with transmission parts.

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