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This study presented a theoretical method to find approximated dimensions of the rectangular micro-asperity. The suitable values required for the asperity’s width and its critical length are found for different values of the flow speed. Numerical calculation is carried out using the solidworks flow simulation; the simulation results illustrated the flow speed trajectory, the variation of the shear stress and the flow pressure on different faces of the micro-asperities. The turbulence area due to the micro-asperity geometry is localized. The prediction of the maximum wear area, due to the skin friction, is also localized in consideration of the shear stress variation.

The wide use of textured surfaces in lubrication to improve lubrication and tribological characteristics has been remarked recently. The understanding of the textured surface geometric parameters influences on these characteristics could help to improve their applications in industry. This paper presents analyzes the influences of the flow speed and the texture deepness on the lubrication hydrodynamic characteristics (shear stress and friction coefficient). Considering that the loads are only exerted by the fluid on the faces of texture (no external force applied), a theoretical relation has been established between the texture deepness and the shear stress. The numerical simulation, using the software "Solidworks flow simulation," has been also driven, on a Wenzel model of micro-asperity, with the conditions of no-slip at the upper surface and slip on the micro-asperities faces. The shear stress, friction coefficient and pressure have been plotted using different values of speed and texture deepness and then analyzed. A significant reduction of friction coefficient with the increase of speed and also with the increase of deepness has been observed.

This study presents a numerical simulation, using the flow simulation of solidworks 2010; the results showed the flow speed trajectory, the variation of the shear stress and the flow pressure on different faces of the micro-asperities in relation with the face length. The simulation was done in steady state and with the no- slips condition in contact with the upper surface. The flow characteristics were found also with different flow speed. The turbulence area due to the micro-asperity geometry is localized. The flow characteristics (variation of shear stress and flow pressure) are analyzed for the prediction of the maximum wear area due to the skin friction or drag.

This study presents a theoretical method to find the dimensions of rectangular micro asperities, using the principles of hydrodynamics and strength of materials. The suitable value of the width of microasperities is calculated; the critical height of micro asperities is also calculated. The suitable width and the critical height are both calculated with different flow speeds. Numerical calculation is carried out using the solidworks flow simulation, the present study is realized at steady state. The simulation results illustrated the flow speed trajectory, the variation of the shear stress and the flow pressure on different faces of micro asperities. The turbulence area, due to the geometry of micro asperities, is localized. The prediction of the maximum wear area, due to the skin friction, is also localized in consideration of the shear stress variation.