本文藉由光刻微影製程在Hele-Shaw cell中生成兩種尺寸之圓柱形顆粒，作為實驗所使用之異質多孔介質微模型。模型內部以低黏度流體(空氣)驅替高黏度流體(甘油水溶液)使其產生黏性指形，並觀察指形流經異質多孔介質之壓力變化。實驗設計三種粒徑比之模型、三種流率及四種重量百分濃度之甘油水溶液以探討設定參數如何影響模型內壓力之變化。
分析實驗結果後，本文提出二相流中，低黏度驅替流體隨指形前進時產生的黏滯壓降半經驗公式，而高黏度被驅替流體之黏滯壓降半經驗公式已有學者提出，故二相流中兩流體之壓力變化皆可被描述與預測。此外，本文發現異質孔徑界面壓差亦隨設定參數而改變，進而提出一半經驗公式以預測界面壓差，且由實驗與先前學者之研究可知，界面壓差越大將使大顆粒多孔介質之驅替效果上升。

In this paper, heterogeneous porous medium micro-model was made by lithography technology of MEMS. Experiments were conducted using the model to observe the pressure change which is caused by low-viscosity fluid (air) displacing high-viscosity fluid (glycerol aqueous solution). Three particle-size ratios, three flow rates and four concentrations of glycerin aqueous solution were considered to investigate how the experimental parameters affect the pressure change.
After analyzing the experiment results, we proposes a semi-empirical formula that quantified the viscous pressure drop caused by the viscous fingering grows in the two-phase flow, which cover the semi-empirical formula of the viscous pressure drop proposed by previous literature. The pressure changes in two-phase flow can be more precisely described and predicted than before. The experiment found that the pressure difference at the heterogeneous interface changes with the parameters, and a semi-empirical formula was proposed to predict the pressure difference at the interface. It is known from experiments and previous studies that increasing the pressure difference at the interface will enhance the displacing effect in the large granular porous media.

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