流道之幾何結構對質子交換膜燃料電池性能之研究

A Study of the Geometry of Flow Channels on the Performance Proton Exchanges Membrane Fuel Cell

黃天信(Tian-Shin Huang)

指導教授 ： 蔡瑞益

中原大學/工學院/機械工程學系/碩士(2007年)

https://doi.org/10.6840/cycu200700691

摘要

本文探討流道之幾何結構對質子交換膜燃料電池性能之影響，藉由CFD-RC計算流體力學套裝軟體來模擬，首先以交叉型流道為基本模型，改變電池溫度、入口溫度以及陰極進氣方向，整理出合適的操作條件，再針對五種不同流道做一比較，接著再改變不同的氣體擴散層孔隙度以及陰極入口流速，對不同流道之燃料電池性能之影響。
模擬結果顯示，電池溫度為323K、入口溫度為333K以及陰極與陽極流動方向為逆流時，整體性能為較佳。在相同的操作條件下，局部電流密度分佈以蛇型流道、交叉型流道以及Z型交叉流道分布較為均勻，所得到電流密度也比其他流道較佳，整體電池性能也會比其他流道好。不同流道其氣體擴散層孔隙度越大，電流密度也會隨著增加。接著改變陰極入口流速，得到直通型流道、Z型流道、交叉直通型流道流速為8.75 時會得到最佳的電流密度，而蛇型流道與交叉型流道在流速為5.25 時，氣體便可以充分有效的擴散到觸媒層參與反應，在ㄧ定的速度下就可以得到較高的電池性能。

關鍵字

質子交換膜燃料電池 ； 操作條件 ； 流道幾何結構

並列摘要

This study is aimed at under the various geometry of flow channels which affect the proton exchanges membrane fuel cell performance by using the (Computational fluid dynamic) software CFDRC to simulate. Consider the counter flow channel as the basic model at first and choosing different temperature condition of the cell cathode flow inlet direction. After collecting the data of suitable operating conditions, to discuss the five different flow channels and comparing to one another .The following step is to change different gas diffusion layers porosity and cathode inlet velocities. Finally, to make the discussion including the different flow channels which affect on the performance of the cell.
The simulation result shows the temperature of the cell for 333K and the temperature of the flow inlet for 323K while the flow direction is just on the opposite side and cell performance is best. Under the same operating condition for serpentine channel、interdigitated channel and Z type-interdigitated channel exist uniform local current density distribution and the value of the maximum current density is higher than other kinds of channel. So, the optimum cell performance will be obtained as well. In different kinds of flow channels, as if the diffusion layers porosity is getting larger, the electric current density will increase too. The effect of cathode flow inlet velocity to the different channel types, parallel channel,Z type-interdigitated channel and interdigitated-parallel channel as the flow velocity up to 8.75 , we can get the maximum current density. On the other hand, serpentine channel and interdigitated channel under the inlet velocity of 5.25 , gas can abundant and effective diffuse to the catalyst layer to induce chemical reaction in there, and we will obtain the higher performance while under the certain specified velocity .

並列關鍵字

geometry of flow channels ； proton exchanges membrane fuel cell ； operating condition

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