燃料電池陰極流道表面結構效應之研究

A Study of the Effect of Surface Structure in the Oxidant Channel of Fuel Cell Cathodes

黃俊豪(Chun-Hao Huang) ； 傅清揚(Chen-Yan Fu) ； 蔡瑞益(Rury-Yih Tsai)

《先進工程學刊》 2卷3期 (2007/07) Pp. 167-175

https://doi.org/10.29948/JAE.200707.0008

摘要

本文主要研究燃料電池陰極流道經加入連續週期性凸塊後流場的傳輸現象與其產生的效應。文中將藉由改變陰極流道內的氣體傳輸機制以增加陰極壁面的剪應力與流道內壓力，進而帶走更多陰極流道的水氣藉以提高燃料電池效率。文中將從所設計的幾種流道內找到較適合的流道機制，以供燃料電池設計人員參考設計。
結果顯示：(1)具有凸塊的流道比傳統無凸塊流道有較大的陰極壁面剪應力與流道內總壓，因為凸塊會阻擋氣體，使反應氣體被強迫向下進入擴散層，使氣體燃料因強制對流作用進入擴散層，增加氣體的傳輸速率，並且藉由氣體流動所產生的剪應力，能有效的移除多孔介質中的液態水，故在流道內加入凸塊確實比原流道可移除更多的液態水，更有利於燃料電池運轉。(2)在氧化劑消耗率較高的流道，陰極壁面的剪應力、流道總壓、壓力降較小。(3)紊流狀態比層流狀態有較大的剪應力、流道總壓與壓力降。

關鍵字

擴散損耗 ； 陰極流道 ； 凸塊流道 ； 氧化劑

並列摘要

The purpose of the thesis is to research the phenomemon and the effects of the oxidant transport in the fuel cell cathode channel which adding rough ribs in cycles. In this thesis，we will enhance the shear stress and the total pressure in fuel cell channel by changing the transport mechanisms of oxidant in fuel cell cathode channel. In result, that will be more water taking away from the fuel cell cathode channel，and the fuel cell power density will be enhancing. We will find the more suitable channel mechanism from the designed channel in this thesis, and provide referrence for fuel cell projector.
The results show that : (1)The channel with rough ribs than with the channel without rough ribs have bigger fuel cell cathode channel shearing stress and total pressure, add protruding piece really than flow dish move originally in flowing line except that more liquid water, furthermore help the fuel cell to operate. (2) The shear stress, total pressure, and pressure drop will be smaller in the channel which oxidant consumed ratio is higher. (3) Turbulent model has bigger shear stress, total pressure, and pressure drop than laminar model.

並列關鍵字

diffusion loss ； cathode channel ； ribbed ； channel ； Oxidant