電池數值模擬

除了高溫氣體供應系統以外，另外完成具有初步流道設計的腔體的單極板以供單電池三明 治夾片核心使用。在陽極與陰極的外側必須加上interconnect 以便將反應產生的電能引出到負 荷電器去使用。而且，interconnect 還須包含氣體流道，以便將高溫氫氣引入至陽極，以及將 grid)、單流道蛇紋式(single-channel serpentine)、多流道蛇紋式(multi-channel serpentine)、對角 分歧式(diagonal bifurcation)。

圖五 陽極與電解質介面上不同流道所造成的氫氣質量分率分佈，電池的電壓為 0.3V

其流道面積佔總電導體面積之比值盡量維持在0.63 至 0.66，以期盡量減低 Ohmic resistance 對燃料電池效能之影響，將重心放在流道設計之分析上。經由初步的流場模擬，可得到在所 預估的燃料電池操作進氣量下，不同流道設計內之氣體、電流密度、溫度分佈與所需壓差的 差異。結果顯示，蛇紋式的流道設計在同樣的功率輸出情形下，其流道流阻較大，而容易造 成氣體在電極上分佈不均與較大的溫度梯度等等問題。此初步結果顯示針對完整的電池組進

X

0 0.002 0.004 0.006 0.008 0.01

Y

0 0.002 0.004 0.006 0.008 0.01

Y

0 0.002 0.004 0.006 0.008 0.01

Y

0 0.002 0.004 0.006 0.008 0.01

Y

行電化學、熱流、電性的數值模擬，能在設計初期幫助找出潛在問題。更進一步的流道設計

0 0.002 0.004 0.006 0.008 0.01

Y

0 0.002 0.004 0.006 0.008 0.01

Y

0 0.002 0.004 0.006 0.008 0.01

Y

0 0.002 0.004 0.006 0.008 0.01

Y

5.2.2 電流密度分佈

0 0.002 0.004 0.006 0.008 0.01

Y

0 0.002 0.004 0.006 0.008 0.01

Y

0 0.002 0.004 0.006 0.008 0.01

Y

0 0.002 0.004 0.006 0.008 0.01

Y

道設計會得到較均勻之溫度分佈，這可歸因於在單一流道中的燃料流速較快，導致較佳之散 熱效果的緣故。

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