The possibility of using indirect internal reforming is one of the advantages of high temperature fuel cells. Strong endothermic fuel reforming reactions can be thermally supported by the heat generated due to the sluggishness of electrochemical reactions, diffusion of participating chemical species and ionic and electric resistance. However, when operating at high temperatures, thermal management becomes an important issue. Typical Solid Oxide Fuel Cell reformer use Nickel as a catalyst material. Because of its prices and catalytic properties, Ni is used in both electrodes and internal reforming reactors. However, using Ni as a catalyst carries some disadvantages. Carbon formation is a major problem during a methane/steam reforming reaction based on Ni catalysis. Carbon formation occurs between nickel and metal-support, creating fibers which damage the catalytic property of the reactor. To prevent carbon deposition, the steam-to-carbon ratio is kept between 3 and 5 throughout the entire process. It was found that ceria-based catalyst materials are effective in suppression carbon deposition. This benefits the utilization of methane-rich fuels with a low steam-to carbon ratio. This paper presents three dimensional numerical studies on the fuel reforming process inside indirect internal reforming type solid oxide fuel cell using nickel supported on Samaria doped Ceria (SDC). Using presented model, the velocity field, concentration of the gases and temperature field was calculated due to discuss process in detail.
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