Modelling of gas flow and electrochemical effects in a single chamber-solid oxide fuel cell (SC-SOFC)

A comparison of the gas flow distribution and reactant utilization in a single chamber solid oxide fuel cell (SC-SOFC) between the parallel and perpendicular cell configuration (with respect to the gas flow direction) has been discussed in detail. An electrochemical-fluid coupled numerical model in a five layer membrane electrode assembly (MEA) is developed. The model accounts for the major transports of convective and diffusive mass transfer, electrode kinetics, and potential fields. The results show gas flow and electrochemical effects inside the cell in each configuration and suggest that the parallel design provides better gas flow than perpendicular configuration. A uniform reactant utilization is observed in case of perpendicular design as compared to the parallel configuration. In order to take advantage of both the gas flow and electrochemical performance of the cell, use of a fully porous cell (including porosity of the electrolyte) is suggested in perpendicular configuration. The model can predict the effect of gas flow/ electrochemical performance, especially in situations where several cells are placed at different distances in the duct. The model is solved using COMSOL Multiphysics 3.3a, a commercial finite element analysis (FEM) software package.