The development of high-performance polymer electrolyte membrane (PEM) fuel cells requires the behaviour of the cells to be predicted as accurately as possible. One suitable tool for this is full-cell CFD (computational fluid dynamics) modelling. These models take into account not only the usual fluid mechanics but also electrochemical reactions, current conduction and heat generation and dissipation. ZSW employs these models successfully as part of commercial software packages.
However, these commercial software solutions have the drawback that an implementation of the latest scientific findings by the user is only possible to a limited extent. On the other hand, open-source models offer precisely this option. In terms of predictive accuracy, however, they have so far not been able to keep up with their commercial counterparts.
For this reason, ZSW is expanding on one of the existing models to create an open-source full-cell model that is as general as possible, building on the already proven free CFD package OpenFOAM®. The efforts undertaken as part of the AutoStack-Industrie project (funded by the German Federal Ministry of Transport and Digital Infrastructure) have already produced some promising results. The illustration below conveys an impression of this on the basis of a channel geometry suitable for fuel cells used in automobiles. Differences to commercial software are only visible in the resulting current density distribution, which is mainly due to the fact that the water balance modelling is not yet complete. Other results such as the depicted reactant distribution are already very consistent. The current state of development thus forms a solid foundation for the continuous further development of the open-source model.