Pore-network modeling of liquid water transport in gas diffusion layer of a polymer electrolyte fuel cell
Pore-network modeling of liquid water transport in gas diffusion layer of a polymer electrolyte fuel cell
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DOI：
10.1016/j.electacta.2007.06.061
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发表时间：
2007-11
影响因子：
6.6
通讯作者：
P. Sinha;Chaoyang Wang
中科院分区：
文献类型：
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作者：
P. Sinha;Chaoyang Wang
建立了考虑气体扩散层形态的孔隙网络模型，研究了液态水在气体扩散层中的运动和液泛。首次研究了在实际燃料电池运行条件下，GDL中液态水在孔隙尺度上的输运动力学和饱和度分布的演变。结果发现，毛细作用力控制液态水在GDL中的运输，液态水在与指状液体水锋相连的簇中移动，呈现分形毛细指进特征的凹形饱和度剖面。还研究了GDL-通道界面处的液体覆盖对GDL内液态水输运的影响，发现GDL-通道界面处的液体覆盖导致GDL内的压力增加，导致液态水从优先位置爆发。
A pore-network model is developed to study the liquid water movement and flooding in a gas diffusion layer (GDL), with the GDL morphology taken into account. The dynamics of liquid water transport at the pore-scale and evolution of saturation profile in a GDL under realistic fuel cell operating conditions is examined for the first time. It is found that capillary forces control liquid water transport in the GDL and that liquid water moves in connected clusters with finger-like liquid waterfronts, rendering concave-shaped saturation profiles characteristic of fractal capillary fingering. The effect of liquid coverage at the GDL–channel interface on the liquid water transport inside GDL is also studied, and it is found that liquid coverage at the GDL–channel interface results in pressure buildup inside the GDL causing the liquid water to break out from preferential locations.