隨著環保意識提昇以及為未來極可能發生的能源危機作準備，低污染能源之開發已成為當今能源科技至為迫切的研究目標；而燃料電池為其中最有發展潛力的一個方向。在各式燃料電池之中，又以質子交換膜燃料電池最受重視；因為質子交換膜燃料電池具有可以在室溫下運作、可利用空氣當氧化劑、發電功率大、發動快、污染極低等優點，然而，質子交換膜燃料電池技術仍有許多開發與改進的空間，而其中如何讓質子交換膜燃料電池更輕、更有效率已成為目前能源科技研究重點之一。
本文利用熱流分析軟體FloWorks模擬質子交換膜燃料電池中多孔性極板之氣體滲流特性，並探討相關系統參數(如入口流量、多孔係數、流道間距與多孔性材料厚度等)對於多孔性極板內氣體擴散行為的影響。在文中我們整理數值模擬結果，並探討各系統參數對多孔性極板氣體滲透的交叉影響。我們相信本文所獲得的結論可作為設計燃料電池多孔性極板時的參考依據。

Due to growing environmental protection concerns and limited oil reserves on earth, development of new energy technologies exploiting alternative low-pollution fuels has become an imperious research objective. In such guest, fuel cells are now considered to be a promising solution. Meanwhile, among various types of existing fuel cells, the proton exchange membrane fuel cells (PEMFCs) have received most of the attention, because they can be efficiently operated at relatively low temperatures, use air as the oxidant, produce large power, start fast, and are essentially pollution free. Even so, much work remains to be done to improve the PEMFC technology.

In this thesis, we use the commercial software FloWorks™ to simulate the seepage flow through a porous electrode of a PEMFC. In particular, the effects of various system parameters on the overall seepage characteristics are evaluated. The system parameters considered here include the thickness of the porous backing layer, the spacing of gas flow passages on the flow field/current collector, and the operating pressure. Results of numerical simulations are systematically summarized, and the conclusions are expected to be useful for designing realistic fuel cells.

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