NUMERICAL INVESTIGATION ON HYDRODYNAMIC LUBRICATION CHARACTERISTICS OF MICRO DIMPLE TEXTURED SURFACES

This study deals with the numerical investigation on two-dimensional lubrication characteristics of micro-dimple shapes fabricated on solid surfaces by using the commercial CFD code (Fluent V.6.3) to examine the influence of micro dimple depth and width on the reduction in friction under the sliding plate condition. In addition, single and multiple dimple arrays are simulated, all for a fixed area fraction of dimple on the surface. As a result, it is found that the existence of micro-dimpled surface makes it possible to substantially reduce the friction forces exerted on the surfaces, and such an optimum dimple depth would be present because the dimple depth larger than the optimum value did no longer affect the reduction in shear stresses, indicating that the reduction of friction is likely to be associated with inner flows of lubricant inside dimples. Moreover, it is observed that at the fixed area fraction, the friction reduction increases with the increase of dimple diameter.