Numerical Simulation of Friction-reduction Effect of Micro-textured Surface in Hydrodynamic Lubrication
Saving energy and high-speed transmission parts are required in many fields, such as ultra-precision machine tools.It is an effective way to decrease surface friction by fabricating surface textures.However, the application of low drag surface by modulating textures at the micrometer scale has not been clarified in lubrication film of micro-thickness.In the present research, the effect of shapes and sizes of textures on friction reduction of surface was analyzed.A computational fluid dynamics (CFD) method using Navier-Stokes equations was used to investigate low frictional properties of textured surface.The friction of two types of textured surfaces at micrometer scale were compared with that of a flat surface in a laminar flow.Simulation results suggest that the tailored sawtooth textures can lead to a smaller shear stress at fluid-solid interface in valley area of surface structures than that at fluid-solid interface of a flat surface.The sum of shear stress decrease in valley area is larger than that of shear stress increase in other places of the surface.Therefore, the friction of textured surface is smaller than that of a flat surface.Under pressure difference of 0 Pa between inlet and outlet, the maximum coefficient of friction reduction of 66.9 % was obtained in case of 3μm of film thickness, textures with 20 μm in height and 45° tip angle in laminar follow with local Reynolds number from 2.8124 to 21.56231.The results correspond well with the existing theory of low-friction surface and demonstrate that the proposed surface textures are effective to get a friction-reducing surface.
Hydrodynamic lubrication Microtextured surface Friction-reduction Numerical simulation
Yue SUN Chihiro KATOU Shaolin XU Keita SHIMADA Masayoshi MIZUTANI Tsunemoto KURIYAGAWA
Tohoku University, 6-6-01 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8579, JAPAN
国际会议
长沙
英文
189-197
2016-11-04（万方平台首次上网日期，不代表论文的发表时间）