空气冷却型PEMFC多场耦合仿真分析

Multi-field coupled simulation and analysis of air-cooled PEMFC

通过对多场耦合的三维单通道质子交换膜燃料电池(PEMFC)模型进行仿真,分析阴极极板构型对电堆传质和传导特性的影响。对不同脊槽比、宽度和增加微结构的单通道电池进行研究,发现:脊槽比过小导致接触电阻增大,输出电压减小;而脊槽比过大引起传热、传质性能降低,也会影响输出电压,当脊槽比为3时,输出电压达到相对最优。单通道电池宽度小于4 mm时,宽度越小输出性能越好。增加起伏微结构,促进气体扩散层内扩散流动速度分量,可改善传质特性,反应界面氧气浓度提高13%,输出电压提升。

The effects of cathode plate configurations on transfer and conduction were analyzed by simulating the multi-fieldcoupling three-dimensional single-channel proton exchange membrane fuel cell( PEMFC) models. Through the study of singlechannel fuel cells with different ridge-groove ratios,width and micro-structures,it was found that the increase of contact resistance caused by small ridge-groove ratios and decrease of the output voltage. While the deficiency of mass and heat transfer caused by large ridge-groove ratio and influenced the output voltage. When the ridge-groove ratio was 3,the output voltage was relatively optimal. When the width of single-channel cell was smaller and less than 4 mm,the output voltage was boosted. By adding the waved structure in the channel,the vertical flow velocity in the gas diffusion layer was enhanced with increased oxygen concentration by 13% in the reaction interface,and improving the fuel cell output voltage.