二次流对SOFC燃料电池电化学反应的影响机理研究  

The Influence of Secondary Flow on Electrochemical Reaction in SOFC

作　　者：赵秉国 曾泽智 郝长坤 钱煜平 诸葛伟林[1] 张扬军[1] ZHAO Bingguo;ZENG Zezhi;HAO Changkun;QIAN Yuping;ZHUGE Weilin;ZHANG Yangjun(State Key Laboratory of Automotive Safety and Energy,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学汽车安全与节能国家重点实验室,北京100084

出　　处：《工程热物理学报》2022年第11期3029-3040,共12页Journal of Engineering Thermophysics

基　　金：先进航空动力创新工作站项目。

摘　　要：功率密度低是制约固体氧化物燃料电池(Solid Oxide Fuel Cell,SOFC)广泛应用的瓶颈问题之一,SOFC流道内的二次流特性对其功率密度有重要影响。本文建立了考虑二次流效应的SOFC多场耦合模型,模拟了二次流对SOFC多孔电极内燃料各组分浓度分布、电流密度分布和压降损失的影响,提出了表征二次流传质特性的多孔电极表面速度旋度及佩克莱数。研究结果表明:二次流形成垂直于多孔电极表面的速度,使进入多孔电极的燃料量显著增加,促进了多孔电极内的重整反应与电化学反应。在SOFC多孔电极表面平均佩克莱数达到0.0145时,燃料中甲烷重整率为72.3%,功率密度可提升23.8%。The low power density has impeded the wider adoption of the solid oxide fuel cell(SOFC).The secondary flow characteristics in the SOFC flow channel significantly affect its power density.In this paper,a SOFC Multiphysics model has been developed to simulate the effects of the secondary flow on the fuel concentration distribution,current density distribution and gas-phase pressure drop in the SOFC porous electrode.The surface vorticity and Peclet number are proposed to examine the mass transfer characteristics of the secondary flow.The results show that the formation of the secondary flow perpendicular to the interface between flow channel and porous electrode significantly increases the amount of fuel entering the porous electrode,which promotes both the reforming reactions and electrochemical reactions in the porous electrode.We demonstrate that as the average Peclet number reaches 0.0145,the methane reforming rate reaches 72.3%and the SOFC power density can be increased by 23.8%.

关 键 词：固体氧化物燃料电池 阳极流道 扰流元件 二次流 功率密度 

分 类 号：TM911.4[电气工程—电力电子与电力传动]