Enhancing under-rib mass transport in proton exchange membrane fuel cells using new serpentine flow field designs

摘要

New flow field configurations are developed to improve the performance of polymer electrolyte membrane fuel cells (PEMFCs). The developed designs aim to uniformly distribute the reactants over the reaction area of the catalyst layer surface, boost the under-rib convection mass transport through the gas diffusion layer, decrease the water flooding effect in the gas diffusion layer-catalyst layer interface, and maintain the membrane water content within the required range to augment protonic conductivity. To evaluate the performance parameters of a PEMFC, a comprehensive three-dimensional, two-phase mathematical model has been developed. The model includes the charge transport, electrochemical reactions, mass conservation, momentum, energy, and water transport equations. The results signify that the improved flow field patterns attain a considerable boosting of the output power, the under-rib convection mass transport, improvement of the reactant distribution over the catalyst layer surface and decline of the liquid water saturation in the gas diffusion layer-catalyst layer interface. The developed configurations achieve a higher power density of 0.82 W/cm(2) at a current density of 1.74 A/cm(2), compared to the standard serpentine configuration, which attains about 0.67 W/cm(2) at a current density of 1.486 A/cm(2) .Accordingly, the develop configurations demonstrate a 22.6% enhancement in power density. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.