Abstract
A multi-stage model of SOFC (Solid Oxide Fuel Cell) has been developed for the system analysis of SOFC/MGT (Micro Gas Turbine). With the present multi-stage model, a fuel cell is divided into several stages (or control volumes) so that it can take into account the spatial variation of the quantities to be treated to some extent. Therefore, it provides information about the internal phenomena of SOFC closer to the reality. Then, a thermodynamic model of a hybrid system has been constructed based on the developed multi-stage model of SOFC. Radiation between solid parts of fuel cell is also taken into consideration. The constructed model was then applied to analyze the performance of an indirect internal reforming type SOFC (IIR-SOFC), commercialized by Siemens-Westinghouse. The predicted results of design point analysis of a 220kW SOFC/MGT hybrid system are in good agreement with the predicted data by Siemens-Westinghouse. Effects of the number of the stages on the performance of hybrid system are also discussed.
