表面亲疏水特性对毛细管内双组分渗流特性的影响

Effect of Surface Hydrophilic and Hydrophobic Characteristics on Percolation of Bicomponent in a Capillary

垫片密封泄漏预测模型一般基于Hagen-Poiseuille定律。该定律适用于气体或液体的单组分泄漏预测,而对于双组分或多组分介质的泄漏,其适用性有待进一步研究。在考虑泄漏通道亲疏水特性的基础上,采用格子玻尔兹曼方法(LBM)模拟矩形微通道内的双组分渗流过程,获得不同密度的双组分介质在毛细管内流动的基本规律。研究发现,通道的亲水和疏水特性对双组分渗流的影响显著,具体表现为黏滞在亲水性壁面上的重组分使流动通道的截面积缩小,从而使轻组分的流量下降。研究表明,双组分在亲水性壁面通道内的流动不同于一般的双组分混合流动,因此在利用Hagen-Poiseuille定律预测渗流时需对公式进行修正。

The leakage prediction model for gasket static seal is theoretically based on the Hagen⁃Poiseuille law.This law is generally appropriate for the prediction of single-component leakage of gas or liquid,while its applicability remains to be further researched for the leakage of bi-component or multi-component media.Considering the hydrophilic and hydrophobic characteristics of leakage channel,the fundamental flow pattern of bi-component media with different densities in capillary was obtained by means of utilizing the Lattice Boltzmann Method(LBM)to simulate the bi-component percolation process in the rectangular microchannel.It is suggested that the hydrophilic and hydrophobic characteristics of the channel have a significant influence on the bi-component percolation,which results in the shrink of cross-sectional area and a slowdown of light component in traffic.The shrink of cross-sectional area arises from heavy component adhering to the hydrophilic wall surface.The results show that the bi-component flow in the hydrophilic wall channel is different from the general bi-component mixed flow,so the formula needs to be modified when using Hagen-Poiseuille law to predict percolation.