A theoretical evaluation of the ohmic resistance of solid oxide fuel cells (SOFCs) is very important because internal ohmic resistances account for a large part of the losses occurring in SOFCs and significantly affect cell performance. However, in the majority of cases, a detailed evaluation of ohmic losses is not an elementary task, since the structure of the geometry makes it difficult to apply simple laws, such as $R=ρl∕S$. The solution of a PDE equation is required, which has to be performed numerically. In this paper, two different numerical approaches have been applied to the simulation of the internal ohmic resistances of basic SOFC units, and the results have been compared. In particular, the commercial mathematical software FEMLAB and MATLAB have been used to implement the different numerical approaches. The agreement between the obtained results is very good.

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