PEMFC梯度扩散层水传输模型的研究

质子交换膜燃料电池（PEMFC：Proton Exchanges Membrane Fuel Cell）水管理是其可靠高效运行的关键，利用多孔介质毛细压力理论建立了PEMFC梯度扩散层液态水传输模型。在此基础上计算了催化层／扩散层和扩散层／流道界面上相饱和度差值为一定值时不同结构扩散层的液态水通过能力，就扩散层孔隙率对液态水传输的影响进行了分析。认为扩散层的过水流量随孔隙率的增加而增加，同时又随孔隙率的增加而增加。即如果扩散层具有较大孔隙率和较大孔隙率梯度，PEMFC可以发出更大的电流密度，而膜电极可能不会产生水淹现象。

Research on Liquid Water Transport Model for Gradient Structure Gas Diffusion Layer of PEMFC

Water management is critical for high performance of proton exchanges membrane fuel cell(PEMFC).The liquid water transport model for gradient structure gas diffusion layer of PEMFC was established based on the capillary pressure theory,and then the liquid water flux through GDL was calculated based on the assumption that a fixed liquid saturation difference exists between the interfaces of catalyst layer/GDL and GDL/gas channel,the results were analyzed.Results showed that under steady condition the liquid water flux through GDL increasing with the increasing of porosity,GDL with gradient porosity was more favorable for liquid water to be discharged from MEA to gas channel;the larger the gradient was,the more easily the liquid water was to be discharged out.