Numerical study of the effect of lip surface roughness on lubrication of radial shaft seals with a simple sinusoidal model

The effect of lip surface microtopography on lubrication of radial shaft seals is studied numerically. Numerical analysis of hydrodynamic flow at the lip is conducted with a simple sinusoidal wave as a lip surface asperity model. In order to understand the effects of lip surface microtopography on micro EHL, amplitude, wavelength, curvature and asperity ratio on film formation are investigated. It is found that the wavelength, the curvature and the aspect ratio significantly affect film formation and the coefficient of friction, and that coefficient of friction is influenced not only by minimum film thickness but by the average film thickness.