本論文之目的主要探討微甲醇燃料電池中，陽極產生的二氧化碳及陰極中的水，在觸媒層、擴散層、微流道內的影響。由於二氧化碳及水的產生，在微流道中累積化學反應的產物會堵住流道，導致降低甲醇燃料電池的效率，所以在此要研究經由改變哪些參數，在微尺度的二相流中可以有效的改善陽極二氧化碳氣泡的排除及陰極液態水的移除，即達到改善甲醇燃料電池的持久性及效能。經由數值流力模式，選擇流體體積法來模擬微流道中陽極甲醇溶液的二氧化碳氣泡和陰極空氣中的液態水。其中選擇的變因有接觸角、傾斜角、溫度和流道的幾何形狀等，藉由改變這些參數來討論在微流道中，界面力、表面張力、浮力等影響的輕重。液氣的共存的界面中，不同的液體會有不同的密度和表面張力係數，表面張力不同導致氣泡形狀上的變化，氣泡的速度則隨各種不同參數(密度、黏滯係數、表面張力係數等)會有不同變化。從陽極微流道模擬的結果可以發現，陽極中較低的接觸角，即選擇較親水性的材質，對於氣泡移除的速度較有效；傾斜角的增加等同於多了浮力造成速度上的增加，所以也有利於氣泡的排除；增加溫度會降低表面張力，表面張力降低時氣泡會有些微的速度增加，可以利用增加溫度來改善原本無法從細孔通過的氣泡從細孔中穿過。陰極的擴散層中，主要的結論可以發現，氣體擴散層中的親疏水性特徵，在氣體擴散層表面浮出的水滴行為上有很明顯的效應。越疏水性(接觸角越大)越有利於液態水的排除，空氣速度越大或水流速越快，越有利於吹出液態水珠。隨著氣體擴散層表面材質疏水性的增加，移動水流的空氣臨界速度就減少；隨著增加液態水滴流出孔徑的寬度，移動水流的臨界速度也變小。所以，在微尺度中，在不施加外力的條件下，界面力和表面張力就變成扮演影響氣泡行為很重要的因素。

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