反應物濕度與熱傳遞對棋盤型流道 燃料電池性能之影響

Effect of reactant humidity and heat transfer on the cell performance of PEM fuel cells with grid flows

傅裕書(Yu-Shu Fu)

指導教授 ： 蔡瑞益

中原大學/工學院/機械工程研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000542

摘要

本文探反應物溼度與熱傳遞對質子交換膜燃料電池性能以及壓力損失之影響，藉由CFD-RC計算流體力學套裝軟體來模擬，首先基本架構以棋盤型流道燃料電池為基礎模型，建立蛇型流道燃料電池作對照，模型皆以相同之操作參數做設定，針對傳統蛇型以及棋盤狀流道做性能以及內部現象之比較；接著改變不同的陽極燃料和陰極氧化劑濕度設定作比較分析；再加入壁面熱傳條件，觀察電池內、外部熱傳遞對燃料電池整體熱分佈以及性能之影響。
模擬結果顯示，在相同的操作條件下傳統蛇型流道與棋盤式流道燃料電池性能相當，卻能壓力損失減少。當陽極反應物溼度為RHa=75%時性能較佳，陰極反應物相對溼度在RHc=100%時所得到的電流密度最大。接著改變電池內部熱傳導係數時，電池內部的熱源分佈也受到影響，較高的熱傳導係數，電池的電流密度也較高；改變電池外部熱對流係數時，影響電池整體散熱，當熱對流係數越高時，電流密度也隨之增加。

關鍵字

棋盤式流道 ； 熱傳遞係數 ； 反應物相對溼度 ； 質子交換膜燃料電池

並列摘要

This study is aimed at under the various geometry of flow channels which affect the performance and pressure drop of proton exchanges membrane fuel cell by using the (Computational fluid dynamic) software CFDRC to simulate. At first consider grid flow channel as the basic model to compare with senpentine flow channel. Both of them are set in the same condition. Directed at comparison of the performance and the internal phenomena between senpentine flow channel and grid flow channel. Then, change the different humidity of reactants on andoe and cathode. Add the condition of the effect of the wall heat transfer; observed the effect of heat distribution and performance of internal and external heat transfer for fuel cell.
The simulation result shows the performance of grid flow channel is similar to that of the performance of senpentine flow channel; the pressure drop, but the grid flow channel can reduce the pressure drop. The performance of PEMFC is better when the humidity of reactant on anode is RHa=75%. We can get the maximum current density when the humidity of reactant on cathode is RHc=100%. The heat distribution is effected on fuel cell when the heat conduction coefficient changed. If the heat conduction coefficient is getting larger, the current density will increase too. If the heat convection coefficient is getting larger, the current density will increase too, and then affect the cooling rate.

並列關鍵字

PEM Fuel Cell ； grid ； heat transfer ； humidity

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