Two-phase flow and transport in the air cathode of proton exchange membrane fuel cells

JOURNAL OF POWER SOURCES

卷:94

Article

Wang, ZH ; Wang, CY ; Chen, KS

关键词: two-phase transport;    PEM fuel cells;    analytical modeling;    numerical simulation;    water management;   

DOI  :  10.1016/S0378-7753(00)00662-5

来源: Elsevier

【 摘 要 】

Two-phase flow and transport of reactants and products in the air cathode of proton exchange membrane (PEM) fuel cells is studied analytically and numerically. Single- and two-phase regimes of water distribution and transport are classified by a threshold current density corresponding to first appearance of liquid water at the membrane/cathode interface. When the cell operates above the threshold current density, liquid water appears and a two-phase zone forms within the porous cathode. A two-phase, multicomponent mixture model in conjunction with a finite-volume-based computational fluid dynamics (CFD) technique is applied to simulate the cathode operation in this regime. The model is able to handle the situation where a single-phase region co-exists with a two-phase zone in the air cathode. For the first time, the polarization curve as well as water and oxygen concentration distributions encompassing both single- and two-phase regimes of the air cathode are presented. Capillary action is found to be the dominant mechanism for water transport inside the two-phase zone of the hydrophilic structure. The liquid water saturation within the cathode is predicted to reach 6.3% at 1.4 A cm(-2) for dry inlet air. (C) 2001 Elsevier Science B.V. All rights reserved.

【 授权许可】

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