拔模角对质子交换膜燃料电池流场的影响

Effects of draft angle on PEMFC flow fields

模铸法制备质子交换膜燃料电池双极板对于降低燃料电池的制造成本有着重要意义。而模铸过程中模具拔模角度的变化,会引起双极板上流道的截面形状的变化。为了研究拔模角对流场性能的影响,在燃料电池CFD模型和实验所得参数的基础上,对阳极与阴极分别采用单通道和四通道蛇形流场、拔模角从0°到30°条件下的50 cm2单电池的流场进行了模拟计算。研究发现,随着拔模角的增大,阳极与阴极侧流道总压降先下降后上升,气体扩散层漏流量和到达反应层气体浓度则一直增加。综合考虑,建议选择阳极和阴极侧拔模角分别为14°～25°和10°～18°。

Preparing PEMFC bipolar plate by moulding presses is very meaningful to reduce the manufacturing cost of PEMFC.But with the variation of draft angle during moulding process,the channel has a different cross-sectional shape.In order to study the effects of draft angle on performance of the flow fields,based on CFD modeling as well as experimental parameters,the flow fields of a 50 cm2 single cell were simulated and calculated.The single-channel serpentine flow fields were used in the anode,while four-channel serpentine flow fields were used in the cathode,and the draft angle was ranged from 0° to 30°.The results show that with the increase of draft angle,the pressure drop of the flow fields in both anode and cathode decrease at first and then increase,the flow cross-over through the gas diffusion layer and the gas concentration in reaction zone increase as well.The optimized draft angle from 14°to 25°for the anode and the one from 10° to 18° for the cathode were suggested.