Computational study of heat and mass transfer issues in solid oxide fuel cells

Temperature uniformity contributes to minimizing material stress and improving lifetime in solid oxide fuel cells. This paper investigates the temperature distribution in three flow field configurations: co-flow, counter-flow and cross-flow. A three-dimensional computational fluid dynamics model coupling transport and electrochemistry is developed within the framework of an existing open source library. Porous electrodes with effetive diffusivities and interconnect rib geometries are accounted for. Two different approaches were investigated ain obtaining effective diffusion coefficients for the porous transport layers. A lumped internal resistance model is implemented for the calculation of electrochemical reaction and Joule heating. The temperature profiles are influenced by the fluid (either air or fuel) flow passage and the interconnect rib geometry. Among the three geometry configurations considered, the counter-flow case produces the most uniform temperature distribution with the smallest temperature variation.