本研究利用H2SO4水溶液及NaHCO3水溶液在流道中混合後進行化學反應，生成CO2氣泡，用以模擬直接甲醇燃料電池陽極端的雙相流行為。將不同濃度之H2SO4水溶液及NaHCO3水溶液通入由壓克力製成的蛇形等截面積流道 (SSF)、漸擴流道 (SDSF-2°, SDSF-3°)以探討雙相流現象。
研究結果顯示：流譜的觀察中，三種流道上游的流譜大都為氣泡流，流道下游的流譜大都為袋狀流或是環形流。在工作流體濃度低的實驗條件下，漸擴流道SDSF-2□中較少CO2氣泡產生，其原因可能是在漸擴流道SDSF-2□中流體流動的速度較快，造成工作流體混合效果較差，使化學反應不易發生，氣泡生成較少；在漸擴流道SDSF-3□流動的工作流體速度較慢的影響下，混合效果較佳，有利於化學反應的發生，氣泡生成較多。CO2氣泡在轉角處生成較多，可能是因為流體流經轉角處會產生二次流。三種流道中生成的CO2氣泡，大致上均呈現線性成長的模式。
實驗壓降部分，漸擴流道SDSF-3□中的實驗壓降值較等截面積流道(SSF)及漸擴流道SDSF-2□中的實驗壓降值為低。在不同實驗條件下，可發現壓降皆有一高頻振盪，其頻率約為45Hz，這可能是聲波振盪的表現。

The present study utilizes sulfuric acid (H2SO4) solution and sodium bicarbonate (NaHCO3) solution mixing in the minichannel to produce carbon dioxide (CO2) through chemical reactions to simulate the two-phase flow transportation at the anode side of a DMFC through the following chemical reaction.
Research results shows that the upstream flow pattern in three kinds of flow channel (SSF, SDSF-2□, SDSF-3□) is mostly bubbly flow; the downstream flow pattern is mostly slug flow or annular flow. Few CO2 bubbles are generated in SDSF-2□□Under the condition of low concentration. This could be the fluid velocity in SDSF-2□□□is fast, causing poor mixing of two working solutions On the other hand, more CO2 bubbles are produced in SDSF-3□□due to slower fluid velocity, and the mixing of two working solutions is better. More CO2 bubbles are generated at U-bends. This could be when fluid flow through a U-bend, a secondary flow will take place there. The CO2 bubbles are generated in three kinds of flow channel growing approximately linearly.
The experimental pressure drop part, the pressure drops in SDSF-3□ is lower than those of SSF and SDSF-2□□ All of the two-phase pressure drop data exhibit a small amplitude, high frequency oscillation of about 45Hz.

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