针对航空泵用机械密封实际操作条件,考虑粗糙表面弹塑性接触,基于质量守恒的JFO(Jakobsson-Floberg-Olsson)空化理论建立了倾斜粗糙端面机械密封环的液体润滑和混合润滑计算模型;采用有限单元法求解PC(Patir and Cheng)平均Reynolds方程,获得端面液膜的压力分布;对比研究了在不同的密封压力、中心膜厚和转速条件下,端面倾斜角对粗糙表面和光滑表面机械密封性能参数的影响规律.结果表明:随着倾斜角增大,端面的承载力增大,摩擦力先减小而后增大,泄漏率增大;当端面倾斜角较小时,粗糙表面机械密封性能优于光滑表面机械密封性能.
To improve lubrication effect and seal performance, complicated geometrical hydrodynamic grooves or patterns are often processed on end faces of liquid lubricated mechanical seals. These structures can lead to difficulties in precisely estimating the seal performance. In this study, an efficient adaptive finite element method （FEM） algorithm with mass conservation was presented, in which a streamline upwind/Petrov-Galerkin （SUPG） weighted residual FEM and a fast iteration algorithm were applied to solve the lubrication equations （Reynolds equation）. A mesh adaptation technique was utilized to refine the computation domain based on a residual posterior error estimator. Validation, applicability, and efficiency were verified by comparison among different algorithms and by case studies on seals＇ faces with different groove structures. The study investigated the influence of the order of shape function and the mesh number on the leakage balance. Mesh refinement occurred mainly in cavitation zones when cavitation happened, otherwise it occurred in regions with a high pressure gradient. Numerical experiments verified that the proposed algorithm is a fast, effective, and accurate method to simulate lubrication problems in the engineering field apart from end face seals.
