討微型直接甲醇燃料電池(micro direct methanol fuel cell, uDMFC)陽極微流道內CO2氣泡之移除情形。在介觀(mesoscopic)尺度下，使用熱晶格波茲曼法(Thermal Lattice Boltzmann Method, LBM)用於模擬液氣雙相流(甲醇水溶液/CO2氣泡)的流動現象及排除方法。

以水平放置的微流道，觀察其流動情形與排除速度，其中考慮表面張力(surface tension)、液固介面力(fluid-solid interaction force)與浮力(buoyancy force)，並有考慮溫度影響。從不同幾何形狀，以及流道管徑、親疏水性表面性質、幾何形狀與溫度變化等等問題探討，並針對熱毛細效應(Marangoni effect)研究其效果。藉此了解並排除氣泡阻塞在微流道內的情況發生。

直管微流道內，以較親水表面氣泡移動速度最快；而較疏水、漸親水與漸疏水表面其氣泡移動速度均較慢。利用熱毛細效應時，則漸高溫之流場氣泡移動速度會變快；而漸低溫之流場則會變慢。當入口出口溫差越小時，則會因熱毛細效應減弱使氣泡往高溫區移動的驅動力變小，氣泡移動速度變慢。利用此效應使阻塞在孔洞的氣泡順利通過，則以前段漸高溫流場為最佳，熱毛細效應效果最好，入口流速所需最低即可順利通過孔洞。

漸縮式、漸擴式與直管微流道之入口質量流率均相同，且單位時間內流量體積亦相等。在高溫流場內，漸擴式的氣泡移動速度較快。當採漸高溫流場時，其氣泡移動速度提升最多且最快，即利用熱毛細效應使氣泡往高溫區移動的效果最佳，其對於氣泡移除最為有利。

總結此研究，較親水表面或漸高溫流場，皆較有利於氣泡移除，而漸擴式親水性表面微流道之漸高溫流場為最佳。故此類型之微流道，將最有利CO2氣泡的移除，以提高微型直接甲醇燃料電池之整體性能。

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