Lubricated textured plan parallel sliding contacts: the effect of boundary slip and cavitation

Surface texturing is an effective approach to increasing the tribological performance of lubricated mechanical components. It is known that introducing textured surfaces can significantly affect friction and load support of sliding bearings. Recently, in addition to surface texturing, the use of an artificial boundary slip surface is also of great interest with respect to lubrication. It is worth noting that when the effect of boundary slip is of particular interest in bearing analysis, for most previously published works cavitation was ignored, and most of them used a non-mass conserving equation.
As is known, cavitation in a bearing is common and directly influences the hydrodynamic pressure and, subsequently, the load support and friction of the contact. In order to address such a cavitation effect, several cavitation models have been proposed by numerous researchers. In this research, the focus is on modifying the Reynolds equation by considering the cavitation model in which the mass conservation along the lubricated contact is fulfilled. The hydrodynamic performance of a textured contact with boundary slip is investigated through analytical and numerical simulations.
In the present work, an analytical equation based on the Reynolds theory is derived. In this way, the Reynolds equation is extended by considering boundary slip and cavitation. Here, boundary slip is varied with respect to the location on the lubricated contact. For a single and double pocketed slip bearing, a mathematical model including boundary slip and cavitation has been developed, from which expressions of the pressure and flow rate can be derived. The global contact geometry in this study is that of a rectangular textured sliding surface.
The significance of the cavitation effect in the lubrication analysis based on the developed model is investigated. Analytically, the cavitation and no cavitation condition with boundary slip and no-slip on parallel slider bearings with a single texture is discussed. It is found that adding boundary slip can reduce the cavitation area, affecting the pressure and load support of the textured slider bearing.