Abstract
Three main kinds of irreversibilities exist in SOFC due to the presence of porous electrodes and electrolyte. Those are concentration overpotential, ohmic overpotential and activation overpotential. Appropriate overpotential model is a fatal factor for the successful modeling of electrical performance, heat and mass transfer of SOFC. In this paper three different activation overpotential models have been compared for tubular SOFC simulation. The results of current density, output power and the temperature distribution within a tubular SOFC unit are discussed in detail.
