Three-dimensional simulation of solid oxide fuel cell with metal foam as cathode flow distributor

Abstract

In this study, the use of metal foam as a flow distributor at cathode is evaluated numerically by a comprehensive three-dimensional solid oxide fuel cell (SOFC) model. The results show that the adoption of metal foam improves the power density by 13.74% at current density of 5000 A m−2 in comparison with conventional straight channel design. It is found that electronic overpotential, oxygen concentration and reaction rates distribute more uniformly without the restriction of ribs. The effects of cathode thickness on the two different flow distributors are compared. Compared with conventional straight channel, the metal foam is found to be more suitable as a distributor for anode supported SOFC with thin cathode gas diffusion layer. Moreover, when metal foam is applied to the fuel cell with a larger reaction area, a more uniform velocity distribution and a lower temperature distribution can be achieved. It is also found that an appropriate permeability coefficient should offer a reasonable pressure drop, which is beneficial for the fuel cell system performance improvement.