本文利用多參數之最佳化程序與實驗設計方法(DOE)，以全因子法(full factorial experimental design)及基因演算法(genetic algorithm method)搭配計算流體力學(CFD)，以數值模擬一氣體擴散層連接波浪狀/波形渠道。文中所述之模型基本上是以一質子交換膜燃料電池內之陽極氣體流道之流場與熱傳特性作數值研究。利用Forchheimer-Brinkman所推導之達西模型及多孔性材質之雙方程能量模型(two-equation energy model)描述多孔性材質內部的流場及熱傳特性，應用控制體積法結合SIMPLE法離散求解一三維穩態層流之橢圓偏微分方程問題。
首先將波浪狀渠道之模擬結果與文獻中可用之結果作仔細的驗證，再針對波形渠道做進一步的研究。波形渠道數值計算的研究參數包含：雷諾數(Re)、波形振幅 α、波數β、擴散層孔隙率ε。研究探討的範圍為200≦Re≦1000，波形振幅0.1≦α≦0.3，波數2≦β≦10，擴散層孔隙率0.4≦ε≦0.5。
文中提供雷諾數(Re)、波形振幅(α)、波數(β)、擴散層孔隙率(ε)四參數相互影響與局部紐賽數(Nu)和平均紐賽數(Nu)之比較。結果顯示有加入波浪狀及波型渠道的流道在計算局部紐賽數及平均紐賽數均明顯優於直流道的狀況，在入口處有最大值，而隨著流動方向而遞減，並且隨著雷諾數增加而提高。
文中另外利用全因子法(full factorial experimental design)和基因演算法(genetic algorithm method)得到目標函數熱性能係數E(Thermal Performance Factor)與三設計參數波形振幅α、波數β、擴散層孔隙率ε之間的關係式，並得到在不同雷諾數下之最佳幾何外型。

In this study, the multi-parameter constrained optimization procedure integrating the design of experiments (DOE), full factorial experimental design (FFED), genetic algorithm (GA) and computational fluid dynamics (CFD) is proposed to design a gas diffusion layer (GDL) linked to a wavy-like/wavy channel. This model is on the basis of an anode flow channel inside a proton exchange membrane fuel cells (PEMFC) and the fluid flow and heat transfer characteristics have been investigated numerically. The Forchheimer-Brinkman extended Darcy model and two-equation energy model are adopted to describe the fluid flow and heat transfer characteristics in the porous media. The elliptical, coupled, steady-state, three-dimensional governing partial differential equations for laminar forced convection are solved numerically using the finite volume approach. The two energy equations in porous media are solved using finite volume method with SIMPLE technique.
Solutions within wavy-like channel are first validated with available results in the literature and wavy channel is further studied. Numerical computations are performed with wavy channel for the parameters studied Reynolds number (Re), wave amplitude α, wave number β and gas diffusion layer porosity ε in the range of 200≦Re≦1000, 0.1≦α≦0.3, 2≦β≦10, 0.4≦ε ≦0.5 respectively.
The interactive effects of Re,α,β, and ε on the local Nusselt number (Nu) and average Nusselt number(Nu) are provided in this study. The results show that computations of local and average Nusselt number within wavy-like/wavy channel are enhanced compared to the straight channel. There is a maximum value of local Nusselt number at the entrance, and decrease as flow direction, and as the Reynolds number increases.
In addition, the optimization of this problem is also presented by using full factorial experimental design and genetic algorithm(GA) method. The objective function E which is defined as Thermal Performance Factor has developed a correlation function with three design parameters, wave amplitude α, wave number β and gas diffusion layer porosity ε. According to the optimal results, optimum shape conditions were obtained at three different Reynolds numbers.

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