液压缸活塞表面微织构动压润滑性能分析

Analysis on Hydrodynamic Lubrication Performance of Micro-texture on Hydraulic Cylinder Piston Surface

以织构化间隙密封液压缸为研究背景,利用平均雷诺方程对缸筒与活塞的配合处微织构流场进行数学建模,采用有限差分法对平均雷诺方程进行离散,分别对织构形貌为球缺面、圆柱面、圆锥面、抛物面、六面体和正方体进行数值模拟,获得最优微织构形貌,同时探讨了表面粗糙度,表面方向参数和面积占有率对表面摩擦因数的影响。结果表明:六种不同形貌的微织构均能在活塞表面产生动压润滑效果,圆柱形微织构表面动压润滑性能最好;粗糙表面的粗糙峰在运动过程中能够形成动压承载力,圆柱形表面的摩擦因数随粗糙度的增加而增加,微织构的摩擦因数随表面方向参数的增加而减小,随着面积占有率的增加而减小。

The paper was on the background of the textured cylinder clearance seal. The average Reynolds equation was used in the micro-texture flow field for mathematical modeling. The finite difference method was used to discrete the average Reynolds equation. There are six morphologies such as hemispherical surface, cylinder, paraboloid, six-sided cube and micro-textured simulated for getting optimal micro-textured appearance. The effects of the surface roughness, surface orientation parameters and area occupancy rate on the surface friction coefficient are explored. The results show that six different morphologies can produce hydrodynamic lubrication on the surface of the piston. The hydrodynamic lubrication performance of the cylinder is the best. The rough surface asperities can form dynamic pressure bearing force during exercise. The cylindrical surface friction coefficient increases with the roughness. The micro-texture coefficient of friction decreases with the increase of surface direction parameters, area occupancy rate.