Impact of Porosity on Thermal Gradients in Metal-Supported SOFCs: A CFD-Based Analysis

This study presents a computational fluid dynamics (CFD) analysis of the thermal and electrochemical behavior of metal-supported solid oxide fuel cells (MS-SOFCs), with emphasis on the porosity optimization of the metallic support. Using ANSYS Fluent and the SOFC with Unresolved Electrolyte module, simulations were conducted for support porosities ranging from 20% to 80% while maintaining constant electrode microstructure. The results show that increasing support porosity enhances gas diffusion and current density up to an optimal threshold near 0.4. Above this value, performance gains become negligible due to diffusion limitations, and thermal dispersion increases, resulting in sharper vertical temperature gradients (∼10 °C cm −1 ) that approach mechanical stress limits. These findings quantitatively demonstrate the trade-off between electrochemical performance and thermal gradient control, confirming the dual role of the metallic microstructure as both a facilitator of mass transport and a heat-dissipating backbone. The outcomes provide design guidance for selecting appropriate porosity levels to balance power density and thermal stability in MS-SOFC architectures. Additionally, the numerical framework presented here offers a cost-effective approach to accelerate microstructural optimization before extensive experimental prototyping, contributing to the development of more efficient and mechanically reliable MS-SOFC systems for stationary and mobile power applications.