Leakage Model of Metal Static Seal with Two Rough Surfaces Based on the Theory of Porous Medium

doi:10.3901/JME.2022.21.215

Abstract

Abstract: The micro-geometric topography of the rough surface is an important factor affecting the leakage characteristics of static seals. According to the point cloud data of the rough surface, the rough surface is discretized, and the sealing interface consist of two rough surfaces is equivalent to a three-dimensional percolation grid model. The porosity and permeability of the sealing interface are calculated based on the theory of porous medium, and then the leak model of the sealing interface is proposed. Furthermore, a test rig for measuring the leakage rate of metal static seal is set up, the leakage model is proved to be reasonable and correct by sealing experiment. The influences of the direction of the surface texture, the fluctuation frequency of the rough surface and the sealing material on the leak rate are studied. The numerical simulation shows that the sealing interface consisted of anisotropic surfaces has best sealing performance; the fluctuation frequency of the surface is positively correlated with the sealing performance; materials with low hardness are easy to achieve effective sealing; in the case of a high contact load, the effect of surface topography on the leak rate is negligible.

Key words: metal static seal, rough surface, porous medium, three-dimensional percolation grid model, leakage model

CLC Number:

V231

CUI Ying, YU Yingjia, ZHANG Hongxiang, ZHONG Jingjun. Leakage Model of Metal Static Seal with Two Rough Surfaces Based on the Theory of Porous Medium[J]. Journal of Mechanical Engineering, 2022, 58(21): 215-224.

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