The Research Of Hydrodynamic Lubrication Performance On The Surface Of Hydraulic Cylinder Piston With Bionic Micro-texture

The energy consumption problem caused by friction is a topic that can not be neglected in the development of science and technology,Bionic micro-texture as an effective means of friction reduction and lubrication has been widespread concern of sholars at home and and abroad.This paper takes Hydraulic cylinder Piston-cylinder friction pair as object of the research,by imitating animal and plant surface texture on the surface of piston to decrease the friction and increase the frequency response and stability of Hydraulic system.The technology of surface texture is to decrease friction and increase the lubrication by Processing certain morphology and size array on the surface of friction pair.In order to study the surface texture of different morphology,this paper unify area ratio,depth and other parameters of six different morphologies,the numerical method of Reynolds equation was used to calculate the tribological parameters of each morphology.Through analysis,elliptical and circular morphologies have better tribological properties than other morphologies.By analyzing their parameters,we find that the optimal ratio of depth of ellipse to its major axis is e1=0.05-0.06,and the optimal ratio of minor axis of ellipse to its major axis is e2=0.5,and elliptical vertical arrangement is better than parallel arrangement.The optimal ratio of depth of circle to its diameter is e=0.03,the optimal angle is about ? =70°.Compared with optimal area ratio,the optimal area ratio of elliptical texture 10%-15% is smaller than circular texture 15%-20%.And in certain range,larger piston speed and smaller gap oil film thickness has greater pressure and better lubrication performance.Finally,this paper introduces average Reynolds equation to calculate the lubrication performance of surface texture under surface roughness effect.Through analysis,friction and load capacity of the two morphological surface texture both increase with the rise of surface roughness? in the range of 0.5um to 2um,but the magnitude of friction is bigger than load capacity,so the friction coefficient increase with the rise of surfaceroughness.Simultaneously,when the roughness ? is certain,direction parameter ? can affect the flow of lubrication oil;the bigger of direction parameter?,the smaller influence on the flow of lubrication oil,and the friction coefficient of the textured-surface will be decreased.