Modeling two-phase flow in the porous electrodes of proton exchange membrane fuel cells using the interdigitated flow fields

摘要

A two phase transprt model based on Darcy's law, interfacial drag and capillary diffusion was developed to investigate the effects of liquid water transport on the performance of a cathode of a proton exchange membrane fuel cell using an interdigitated flow field. The model results showed that liquid water transport by capillary force and the shear force of gas flow and evaporation are the two main removal mechanisms of liquid water from a cathode using an interdigitated flow field. In regons close to the reaction interface where the effect of gas flow is low, capillary diffusion is the dominant liquid water transport mechanism. Once liquid water is brought to the gas flow dominant regions, the shear force of gas flow carries it out of the electrode.