定開孔率下流道設計與疏水流場對質子交換膜燃料電池之性能影響

The effect of flow field design and hydrophobic field under fixed open area ratio for PEMFC’s performance

蒲瑞台(JUI-TAI PU)

指導教授 ： 曾重仁

國立中央大學/工學院/能源工程研究所/碩士(2007年)

摘要

本實驗藉由實驗方法，利用燃料電池測試系統及以Gore 5621為主體之膜電極組來進行單電池實驗分析，研究中我們主要針對固定開孔率的條件下探討不同流場設計對性能之影響；在操作條件上分別以擺放方向、不同氣體流量、改變陰極加濕溫度、流場疏水處理與改變氧化劑種類來進行性能測試與分析，所得到之結果可以做為未來組裝電池之參考。
由實驗結果可以發現，流場在不同擺放方向下，提升反應氣體流量對單蛇型流場沒有影響，但是對於連續柵狀型與雙蛇型流場可以藉由提高反應氣體之流量來改善水氾濫的情形；隨著陰極增濕瓶溫度提升，加濕量隨著增加，在陰極端容易有水氾濫產生，而雙蛇型流場較容易產生積水的情形，尤其當流場為垂直擺放時。流場經過疏水處理後，單蛇型流場較無明顯之影響，從性能曲線圖中得知，連續柵狀型與雙蛇型流場能藉由流道疏水處理而在水氾濫的情形上獲得改善。當氣體加濕量較低時氣體流動為逆向流時可以藉由電池內部水平衡之效果而維持膜的濕潤。使用空氣為氧化劑時，陰極端由於電池生成水的影響，不需要太高之加濕量，如果提升增濕量，雖然在低電流密度下性能較佳，但是在高電流密度時容易產生水氾濫。

關鍵字

開孔率 ； 疏水 ； 流道設計 ； 質子交換膜

並列摘要

The purpose of this study is to investigate the effect of flow field design and hydrophobic treatment of flow channels on the performance of proton exchange membrane fuel cell under the condition of fixed open ratio of the flow fields. Gore 5621 is used in this work. Operation conditions include flow field orientation (parallel or perpendicular), gas flow rate, cathode humidification temperature, and type of oxidizers.
The results show that increasing the reaction flow rate does not affect the cell performance for single serpentine flow field at both orientations. However, for the series sweep and double serpentine flow fields, cell performance is enhanced by increasing the reactant flow rate. In perpendicular orientation case, double serpentine flow field cell has serious water flooding when the cathode gas is highly humidified. After hydrophobic treatment of the flow field, mass transfer overpotential is reduced for the cells. For low humidification cases, the membrane can remained welled by using the count-flow set up for the hydrophobically treated flow field cases. When using air as the oxidaut, it should not be overly humidified.

並列關鍵字

open ratio ； hydrophobic ； PEMFC ； flow field

參考文獻

9.羅世坤,“流場設計對質子交換膜燃料電池性能之研究,”國立中央大學

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