本文為利用異質孔徑界面增強低黏度空氣於多孔隙介質驅替高黏度矽油效果之研究。實驗採用一水平線性Hele-Shaw cell系統填充含異質孔徑界面之多孔隙介質，此異質孔徑界面為兩種粒徑玻璃珠組成之多孔隙異構性組合系統，內部充滿高黏度矽油。實驗觀察低黏度空氣推動多孔隙介質內高黏度矽油過程中，發現指狀流動為高黏度流體驅替效果低落之原因。為建立一套增強低黏度流體驅替多孔隙介質內高黏度流體之方法，實驗設計五種粗、細玻璃珠所占長度比例不同之多孔隙異構性組合，分別為1:0、3:1、1:1、1:3、0:1，分析不同空氣注入流率對於不同粒徑介質內部高黏度流體驅替之結果。
兩種注入流率實驗條件結果顯示，指形流動受到異質孔徑邊界的阻擋可增強粗顆粒區域玻璃珠內高黏度矽油之驅替效果，並受流率降低影響，指狀流動遂發展為碎形維度較大之指形結構，如結構較大之黏性指形、毛細指形，可增加被驅替流體面積。比較此五組多孔隙異構性組合，發現若縮短粗顆粒區域所占顆粒填充長度，可提高此被驅替流體面積所占百分比，換言之，即可達到較高的空氣注入飽和度。

This research presents an experimental study of enhancing fluid displacement through porous media with a heterogeneous pore-scale boundary, where the displaced fluid (silicone oil) was more viscous than the displacing fluid (air). We used a horizontal linear Hele-Shaw cell with two different sizes of glass beads to model the porous media with different pore sizes. Previous research has shown that a fluid cannot uniformly displaces another relatively more viscous fluid through a porous medium, leaving a finger-like flow pattern in the medium. In order to create a system for more effectively displacing viscous fluid through a porous medium, we proposed a heterogeneous porous medium model. Five different length ratios (1:0, 3:1, 1:1, 1:3, 0:1) of coarse glass bead region to fine glass bead region were considered.
Using this heterogeneous porous medium model, fluid displacement experiments with different air injection rates were performed. Our results showed that much more viscous silicone oil in the coarse glass bead region could be displaced by the less viscous air because the heterogeneous pore-scale boundary prevented the finger-like flow from directly invading into the fine glass bead region. With lower air injection rates the viscous finger had higher fractal dimensions, which could also increase the displaced fluid volume. Comparing the results from the five heterogeneous configurations, we found that shortening the length of the coarse glass bead region increased the ratio of displaced fluid volume in the porous medium, resulting in higher air injection saturation results.

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