Local Non-Equilibrium Thermal Effects in Solid Oxide Fuel Cells with Various Fuels

Local thermal equilibrium (LTE) is a common assumption used in thermal modeling of solid oxide fuel cells (SOFCs). However, its validity has not been fully verified. To examine the validity of the LTE assumption, a thermal model has been developed to evaluate the local thermal non-equilibrium effect of SOFC electrodes with various fuels, considering methane internal reforming and ammonia thermal cracking in the anode. Although the local thermal non-equilibrium effect for ammonia-fed SOFCs was more pronounced than that for hydrogen-fed SOFCs, the local thermal equilibrium assumption can be safely adopted for SOFC modeling for a wide range of operating/structural parameters and for various fuels, such as hydrogen, ammonia, and methane.