LAUSR

Abstract For parallel surfaces, i.e. the oil control ring, the micro-geometry completely determines the hydrodynamic lubrication (HL). The cross-hatched grooves provide a certain load carrying capacity (LCC) and the surface (plateau) roughness can be an additional source. This paper extends earlier work to numerically solve the hydrodynamic pressure and LCC of parallel surfaces with random roughness and/or grooves. The influence of the groove spacing, width and depth on the LCC is studied. Results show that the larger the groove spacing, the higher the LCC. Grooves generate a large part of the LCC when the plateau roughness is small. However, for rough surfaces, grooves decrease the LCC and the wider or the deeper the grooves, the larger the decrease of the LCC.