An experimental study of the displacement of one immiscible fluid by another was performed in microchannels with circular, square and near‐semicircular cross‐sections, with hydraulic diameters from 100 to 200 μm. Experiments were performed over a range of capillary number, Ca, from 0.02 < Ca < 80, with viscosity ratios between the two fluids ranging from 20 to 100. The liquid film left on the channel wall following the advance of the displacing fluid was obtained from visual measurements and a method for the estimation of mean film thickness was shown to be in good agreement with existing correlations. The addition of a surfactant (Sodium Dodecyl Sulfate, SDS) dissolved in the displacing fluid led to a reduction in the thickness of the residual film. © 2018 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers AIChE J, 64: 3456–3466, 2018

中文翻译：

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在大毛细管数下非圆形微通道中的不混溶流体置换后的残留膜厚度

在具有圆形，正方形和近半圆形横截面，水力直径为100至200μm的微通道中进行了一种不混溶性流体被另一种流体驱替的实验研究。在毛细管数Ca从0.02 <Ca <80的范围内进行实验，两种流体之间的粘度比范围为20至100。目测和用于估计平均膜厚的方法被证明与现有的相关性很好地吻合。溶解在驱替液中的表面活性剂（十二烷基硫酸钠，SDS）的加入导致残留膜厚度的减少。©2018 The Authors AIChE Journal由Wiley Periodicals，Inc.出版AIChE J，64：3456–3466，2018