摘要
建立三维PEMFC传输模型,分析阴极流道面积比与阴极流量对交叉型流道质子交换膜燃料电池局部传递特性与电池性能的影响,模型中考虑了液态水生成,以更接近电池实际操作状态.流道面积比代表燃料流动面积与电池总面积之比,较大的流道面积比可提高燃料直接扩散面积,使更多氧气通过扩散方式进入扩散层和催化层参与电化学反应,增进化学反应速率,增大局部电流密度,从而提升电池性能.但对于交叉型流道设计,模拟结果表明,由于流道中挡板的作用,燃料由自然扩散传质转变为强制对流传质,流道面积比的影响被消弱,最佳的电池性能出现在流道面积比为0.4时.结果也显示,提高阴极流量可改善电池性能.通过分析电池内部电流密度、氧气流量和液态水分布等局部传递特性,揭示了流道面积比与阴极流量对电池性能影响的内在原因.
A three-dimensional numerical model of proton exchange membrane fuel cell （PEMFC） has been established to investigate the effects of the flow channel area ratios （Ar ） and the cathode fuel flow rates on the internal transport phenomena and cell performance of PEMFC with the parallel and interdigitated flow channel designs. The effects of liquid water formation on the reactant gas transport were taken into account in the present study. Because At represented the ratio of the flow area of fuel to the cell area, it was expected that higher Ar allows more oxygen to diffuse directly into the gas catalyst layer, which improved the cell performance. Numerical predictions showed that the cell performance apparently increased as Ar increases for the parallel flow channel design. However, for the interdigitated flow channel design, because the fuel transfer manner was converted from diffusion into forced convection, the flow channel area ratios had relatively less effect on cell performance than for parallel flow channel design. The best performance occurs for A r of 0. 4. Numerical predictions also indicate that the cathode fuel flow rate had significant effect on the cell performance. The effects of Ar and cathode fuel flow rate on cell performance are interpreted in terms of the analysis the local current density, oxygen flow rate, and liquid water distribution in cell.
出处
《应用基础与工程科学学报》
EI
CSCD
2008年第6期900-910,共11页
Journal of Basic Science and Engineering
基金
国家自然科学基金(No.50876009)资助
关键词
质子交换膜燃料电池
流道设计
交叉型流道
水管理
proton exchange membrane fuel cells
flow channel design
interdigitated flow channel
water management
作者简介
杨立新（1969-），男，博士，讲师．
通讯作者：王晓东（1973-），男，博士，副教授．E-mail：wangxd99@gmail．com
