Three-Dimensional Simulation of SOFC Anode Polarization Characteristics Based on Sub-Grid Scale Modeling of Microstructure

Three-dimensional numerical analysis of solid oxide fuel cell (SOFC) anode polarization is conducted with a microstructure obtained by a focused ion beam and scanning electron microscope (FIB-SEM). Electronic, ionic and gaseous transports with electrochemical reaction are considered in the porous anode. A sub-grid scale (SGS) model is newly developed and effectively used to consider the structural information whose characteristic scale is smaller than calculation grid size. The proposed SGS models are designed to keep the quality of the structural information which is inevitably lost by resampling process in grid generation. Through comparisons between the simulation results and the experimental data, it was found that the SGS model can either improve the simulation accuracy under a given calculation grid system or reduce computational load for the same degree of simulation accuracy.