PEMFC具有效率高、功率大、低工作温度、低噪声、清洁无污染等优点,极具发展前景。传统PEMFC双极板气体流场中存在气体分布不均匀、"水淹"等问题,因此流场结构优化设计对改善PEMFC性能具有十分重要的意义。为此,设计了3种不同流道数量的PEMFC蛇形流场,并利用COMSOL软件对模型进行多物理场仿真求解,研究了不同流道数量对流场的压力分布、氧气浓度分布、阴极电流密度分布以及气体扩散层中的水浓度分布等的影响规律。仿真结果表明:随着流道数量的增加,流场的进出口压降减小,促进了气体反应物沿流道方向的输送;氧气浓度分布更均匀,促使反应物参与的电化学反应更加充分;排水效果显著增强。

Proton exchange membrane fuel cell(PEMFC)has the characteristics of high efficiency,large power,low working temperature,low noise,clean and pollution-free,which has a bright future.The traditional gas flow field of bipolar plate has the shortcomings of uneven gas distribution,“water”and so on.Therefore,the optimization design of flow field structure can improve the performance of PEMFC obviously.First,three different serpentine flow field of PEMFC were designed in this paper.And then COMSOL software was applied to solve the more physical field problems.At last,the influences of different serpentine flow field on the stress distribution of the flow field and oxygen concentration distribution,the cathode current density distribution and the water in the GDL concentration distribution were analyzed.The simulation results show that the pressure drop between the inlet and outlet is decreased with the increasing of the number of flow passages,which can promote the transport of gas reactants along the flow passages;the distribution of oxygen concentration is more uniform,which makes the reactants participate in the electrochemical reaction more fully;drainage is also more effective.