中文摘要：

针对PEMFC（Proton Exchange Membrane Fuel Cell）多孔电极微结构的特征,提出一个分析该多孔电极极化的两尺度新方法,建立了能够同时在团簇微观和电极宏观两尺度上描述多孔电极内反应和传质、传荷耦联过程的理论模型。该两尺度模型方程为一非线性二阶微分方程组,给出了求解该数模的ADM（Adomian Decomposition Method）与有限差分（Newman′s BAND（J））相结合的便捷方法。还给出了氢PEMFC多孔阴极极化的计算实例,与传统的电极单尺度模型相比,包含微团尺度传质影响的两尺度模型预测值与极化实验数据能更好相符。提出的两尺度新方法也可被相似的多相催化反应系统理论分析所借鉴。

英文摘要：

Aiming at the microstructure of porous electrode in PEMFC （Proton Exchange Membrane Fuel Cell）, a novel two-scale polarization analysis method for the porous electrode was presented, and based on it, a theoretical model was proposed to describe simultaneously the coupled electrochemical reaction and transport process of mass and charge in the porous electrode on both scales of micro cluster and macro size of the electrode. The proposed two-scale model is a set of nonlinear differential equations which can be conveniently solved by using ADM-FDM （Adomian Decomposition Method combining with Finite Difference Method of Newman’s BAND （J））. Furthermore, a computation example about the polarization of porous electrode in PEMFC was presented. Comparing with the conventional used one-scale model of electrode, the computation results of using two-scale model proposed, which considers the influence of mass transport in micro cluster, are consistent better with the experimental data of polarization. The proposed idea of two-scale model may also be used as reference for the theoretical analysis of those reaction systems with heterogeneous catalysis.