渐变型流场对PEMFC传质和性能的影响

Effects of gradually-varied flow field on fuel cell mass transfer and performance

质子交换膜燃料电池(Proton Exchange Membrane Full Cell,PEMFC)流场板结构对燃料电池性能有着重要的影响。在保证模型尺寸和结构尺寸的前提下,建立了阴极、阳极、阴阳极分别具有渐变型流场的质子交换膜燃料电池三维模型,并用有限控制体法对模型进行了求解。结果表明,在大电流区域,渐变形流场可以提高气体的浓差扩散,从而提高电池的性能,但阴极氧气的传输对电池性能的提高远大于阳极氢气的传输对电池性能的提高。因此,阴阳极均为渐变型流场的电池性能最好;阴极为渐变型流场,阳极为直型流场的电池性能次之;阴极为直型流场,阳极为渐变型流场的电池性能再次;阴阳极均为直型流场的电池性能最差。

The structure of flow field has significant influence on the performance of proton exchange membrane fuel cell（PEMFC）. In this paper, PEMFC models with gradually-varied flow field in cathode, in anode, and both were created and solved by means of finite control volume method. The results show that, at high current densities, the concentration diffusion will be improved by gradually-varied flow field, but the effect of the oxygen transfer in cathode is more important than that of the hydrogen transfer in anode, so the fuel cell which has the gradually-varied flow fields both in cathode and in anode has the best performance; that which has the gradually-varied flow fields in cathode and direct floe field in anode has good performance; that which has the direct flow field in anode and gradually-varied flow fields in anode has bad performance; that which has the direct flow fields both in cathode and in anode has the worst performance.