| 引用本文: | 林林,王晓东,张欣欣.直通与交叉流场质子交换膜燃料电池瞬态特性[J].哈尔滨工业大学学报,2010,42(3):472.DOI:10.11918/j.issn.0367-6234.2010.03.030 |
| LIN Lin,WANG Xiao-dong,ZHANG Xin-xin.Numerical study on transient characteristics of PEM fuel cells with parallel and interdigitated flow fields[J].Journal of Harbin Institute of Technology,2010,42(3):472.DOI:10.11918/j.issn.0367-6234.2010.03.030 |
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| 摘要: |
| 研究了质子交换膜燃料电池三维、两相瞬态数学模型,分析了电压负载变化方式、流道与肋条宽度比对直通和交叉流场燃料电池瞬态特性的影响.结果表明,多孔电极氧气浓度偏离其稳态分布是导致电流上冲和下冲的原因;而响应时间由膜中水的含量达到稳态分布所需时间决定.交叉流场相对直通流场在多孔电极具有更高的局部氧气浓度,导致电流上冲峰值与下冲谷值均高于直通流场.随流道与肋条宽度比增加,两种流场响应时间均增长,直通流场电流上冲现象增强,下冲现象减弱,而交叉流场,电流上冲与下冲现象均增强. |
| 关键词: 质子交换膜燃料电池 瞬态响应特性 响应时间 电流上冲和下冲 |
| DOI：10.11918/j.issn.0367-6234.2010.03.030 |
| 分类号:TM911.4 |
| 基金项目:国家自然科学基金资助项目(50876009);北京科技大学冶金研究基金资助项目 |
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| Numerical study on transient characteristics of PEM fuel cells with parallel and interdigitated flow fields |
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LIN Lin, WANG Xiao-dong, ZHANG Xin-xin
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School of Mechanical Engineering,University of Science&Technology Beijing,Bejing 100083,China
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| Abstract: |
| A three-dimensional,two-phase transient model was developed to analyze the transient characteristics of proton exchange membrane(PEM) fuel cells with parallel and interdigitated flow fields.The effects of voltage load changes and channel to rib width ratios on the transient response were examined for both flow fields.The predictions show that the current overshoot and undershoot are mainly resulted from deviations of the oxygen concentration on the cathode diffusion layer-catalyst layer interface from steady-state distributions. The time for the water content in the membrane to reach a steady-state distribution determines the transient response time.As the voltage decrease rate is reduced,the overshoot peak is weakened and the response time is shortened.Since the interdigitated flow field has higher oxygen concentrations on the cathode diffusion layercatalyst layer interface due to forced convection,the overshoot peaks and the undershoot valleys are all higher than those in the parallel flow field.Larger channel to rib width ratio causes longer response time and more overshoot for both flow fields,with less undershoot for the parallel flow field and more undershoot for the interdigitated flow field. |
| Key words: PEM fuel cell transient characteristics response time overshoot and undershoot |
