质子交换膜燃料电池阴极液态水传输模型

Water transport model for cathode of PEMFC

通过分析确定了质子交换膜燃料电池(PEMFC)阴极膜/扩散层界面和流道/扩散层界面出现液态水的临界电流密度值与阴极反应气体流速的关系。建立了阴极液态水传输模型。模型分析得到,在相同电流密度下,阴极膜/扩散层界面的饱和度高于流道/扩散层界面;随电池温度的升高和入口气体相对湿度的降低,膜/扩散层界面水饱和度下降。同时基于文中条件,由水饱和度的瞬态特性分析表明,在较短的时间内水饱和度达到稳态。这些结果将为电池水管理提供依据。

The relation between current density and flow velocity of reactant gas were identified for boundary between the single and two-phase in membrane/diffusion layer and channel/diffusion layer interfaces of the cathode of proton exchange membrane fuel cell (PEMFC). The liquid water transport model for cathode was also developed. The model analysis showed, under the stable state, the saturation in the interface of membrane/diffusion was higher than the one of channel/diffusion layer at the same of current density, and with the temperature of PEMFC increasing and the humidity of reactant gas decreasing, the saturation in the interface of membrane/diffusion layer decreased. Furthermore transient behavior was also discussed and the results showed that water saturation could attain steady state quickly under the conditions given in this paper. These conclusions suggested an effective method of water management for PEMFC.