孔隙介質多相流在地表下的流體傳輸過程中扮演重要的角色，毛細壓力是影響孔隙介質多相流的重要驅動力之一。而接觸角是影響毛細壓力重要的物理量。相關研究顯示，流體流動過程中接觸角會隨著毛細數(capillary number)的不同產生變化。現今，尚未有方法可直接觀測地表下動態孔隙介質流體流動情形，將地下複雜孔隙幾何圖形簡化成微模型圖案並進行注流實驗，是目前觀測動態孔隙介質流的方法之一。本研究藉由高透光性的微模型觀察流體在管道內的變化。
本研究選用PDMS(聚二甲基矽氧烷)片材當作製作微模型的材料。利用微影製程製作矽晶片當作母模，使用PDMS片材翻印母模，讓片材表面留下孔道可供流體流動。本研究用的微模型是 0.1 mm * 0.2 mm的方管孔隙介質幾何圖案。透過高速相機記錄微模型內流體的流動過程，及影像分析軟體量測影像中接觸角隨流速不同的變化。隨著注入流速增加，接觸角都有變大的趨勢。與以往研究結果不同的是隨著流速加大，本研究測得的動態接觸角相關參數α，β並非定值。並將實驗得到的動態接觸角及相關參數α，β修正過往以靜態接觸角為參數的PDM模式，比較修正後的模式結果。

Porous media multi-phase flow plays an important role in the fluid transport process in the subsurface. One of the important driving forces of porous media multi-phase flow is capillary pressure,and the contact angle is one of the important parameter. Related researches show that when fluid flows, contact angle varies depending on different capillary numbers. Up to date, there is no method for direct observation of the flow of porous media fluid underground. The micromodel is one of the mainly used for injection experimental as an tool Highly transparent micromodel is required to observe changes of fluid in tunnels.
This research uses PDMS (polydimehtylsiloxane) sheets as material for the micro-model. Wafer produced by photolithography acts as the substrate. The sheet is laminated with the substrate, leaving tunnels on the surface of the sheet for fluid to flow through. The micro-models used for this research are of two porous media geometric patterns: A. 0.1 mm * 0.2 mm cubic tube. The flow of the fluid in the micro-model is recorded with high speed camera, and the change of the contact angle with respect to flow rate in the images is analyzed by an image analyzing program. Different from the previous results, the dynamic contact angle related parameters α and β measured in this study are not definite as the flow velocity increases. The modified contact angle and the relative parameters α, β are used to modify the PDM model with the static contact angle as the parameter, and the modified model results are compared.

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