Numerical modeling and validation of an integrated module in a reversible solid oxide cell system

This study presents an advanced numerical modeling approach for analyzing a 10/40 kW reversible solid oxide cell Integrated Module designed by Forschungszentrum Jülich GmbH. The present authors extend the distributed resistance analogy method using OpenFOAM to comprehensively simulate the complex physical processes within the sub-components of the Integrated Module. The model incorporates numerical techniques, including the arbitrary mesh interface for sub-component interpolation, a radiative heat transfer model for inter-component heat exchange, and a region-to-region coupling approach for surface and volume temperature coupling. Numerical predictions demonstrate good agreement with experimental measurements in both fuel cell and electrolysis modes, with maximum temperature deviations of 10–15 K observed in the middle parts of the sub-stacks. The model successfully captures the uniform performance across sub-stacks and the high efficiency of the heat exchangers. Analysis of species and current density distributions confirms that the design ensures uniform sub-stack operation, which is crucial for long-term performance. While discrepancies between predicted and reference temperatures in the heating plates are within acceptable limits, the study highlights the potential limitations of simple models in representing real-world systems. This research provides valuable insight into the Integrated Module behavior, enabling informed design optimization and operational strategies. The developed methodology offers a powerful tool for rapid and accurate characterization of reversible solid oxide cell systems, contributing to the advancement of reversible solid oxide cell technology as it scales up for industrial applications.