PEMFC气体扩散层变形对流道内水传输的影响

摘要

The micro-groove model of the gas diffusion layer (GDL) surface in proton exchange membrane fuel cell(PEMFC)gas channels was established. Considering the shedding of the hydrophobic coating on the micro-groove of the GDL surface, the wall in the micro-groove was regarded as hydrophilic. The Volume of Fluid (VOF)model in FLUENT software was used to simulate the water transmission in PEMFC gas channel. It is concluded that the hydrophilic micro-groove on the surface of GDL will obstruct the transmission and discharge of liquid water in the gas channels. The influence of air flow rate on the water transport in the gas channels was analyzed by comparing the volume fraction of liquid water with three different air flow rates. And it was significant for correctly understanding the water transport phenomenon in PEMFC gas channel and improving the water management performance of PEMFC.%建立了质子交换膜燃料电池(PEMFC)流道内气体扩散层(GDL)表面的微型凹槽模型,考虑到GDL表面微型凹槽处疏水涂层的脱落,将微型凹槽内的壁面当作亲水性壁面处理,运用FLUENT软件中的Volume of Fluid(VOF)模型模拟PEMFC处于工况下流道内液态水的传输现象,得出了在GDL表面的亲水性微型凹槽会阻碍流道内液态水的传输及排出的结论,并通过对比三组不同空气流速下流道内液态水的体积分数,分析了空气流速对流道内水传输的影响,对于正确认识PEMFC流道内的水传输现象和提高PEMFC的水管理性能具有重要意义.