Effect Of Bionic Micro Texture On Friction And Wear Properties Of Journal Bearing

In recent years,surface micro texture,as a method that can significantly improve the tribological properties of surfaces,has been widely concerned by scholars,and has become one of the hot research directions in the field of tribology.In order to improve the friction performance of journal bearing to the greatest extent,the paper adopts the methods of theoretical calculation,simulation and experimental test to study the influence of parameters such as micro texture density,size,shape,depth and arrangement on oil film bearing performance,oil film pressure distribution and bearing wear.Firstly,based on the Reynolds equation,the mathematical model of micro textured journal bearing and the mathematical model of micro textured units are established under hydrodynamic lubrication conditions.By changing the size,depth,shape and arrangement of micro textures,the micro texture parameters are calculated.The influence of micro texture shape parameters on the oil film lubrication performance of journal bearing and micro texture calculation unit is studied by changing the size,depth,shape and arrangement of micro textures.Research shows that the appropriate micro texture shape parameters can effectively improve the lubrication performance of journal bearing.Secondly,the simulation model of micro texture journal bearing and micro texture element are established by FLUENT software,and the influence of micro texture shape parameters on oil film pressure is analyzed,and the correctness of numerical calculation results is verified.The results show that the micro texture size,depth,shape and arrangement direction have an impact on the lubricating performance of the oil film.When the micro texture depth is too large,it is easy to produce vortex phenomenon,which has an adverse effect on the dynamic pressure effect of the oil film.When the long side direction of the micro texture is consistent with the movement direction of the friction pair,the lubrication effect is better,which is consistent with the numerical calculation conclusion.Then,based on the Reynolds equation,the mathematical model of the micro textured journal bearing is established considering the influence of the bearing surface roughness,elastic deformation and wear deformation.The influence of different load conditions,micro texture size and bionic micro texture shape on the amount of wear and the proportion of wear are analyzed.The results show that the surface micro texture is suitable for the light load condition and the effect of friction reduction is the best when the shape of the micro texture is fish like and elephant like when the long axis is perpendicular to the axial direction of the bearing,and when the long axis is parallel to the axial direction of the bearing.Finally,fiber laser marking machine is used to process micro texture on the surface of friction specimen.By changing the processing parameters and processing technology,the change rule of micro texture morphology is analyzed to find a better processing method.The change of friction coefficient and wear morphology of micro texture under different lubrication conditions and different friction pair materials was studied by universal friction and wear testing machine.Compared with the theoretical results and simulation results,the reasonable choice of micro texture parameters has an important influence on improving the lubrication performance of journal bearing and reducing the friction coefficient during operation.