Thermal design and modeling of a steam reformer for solid oxide fuel cell fed by natural gas

Abstract

In this study, a compact heat exchanger type steam reformer has been modelled for solid oxide fuel cells fed by natural gas. The commercial CFD code COMSOL Multiphysics has been used for modelling the steam reformer. It has been considered that the heat for the endothermic catalytic reactions in the steam reforming processes is gained from the hot exhaust gases of the solid oxide fuel cell. Thus it has been modelled that these hot gases flow through one side of the heat exchanger. In the other side of the heat exchanger, there is a catalyst area in which the mixture of steam and methane mixture flows through. This area has been modelled as a porous medium because of the catalyst particles. It is shown that hydrogen yield at the exit of the steam reformer and the change of amount of the hydrogen yield are strongly connected with various model parameters. 

Keywords

• COMSOL Multiphysics,Fuel cell,,Hydrogen,Natural gas,Steam reforming

References

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