Multiphysics analysis and optimization of solid oxide electrolysis cells with functionally graded fuel electrodes

This study presents a multiphysics CFD model to understand and analyze hydrogen production and thermal stress in anode-supported planar solid oxide electrolysis cells (SOECs), which employ functionally graded fuel electrodes with engineered linear gradients in porosity, pore size, and Ni composition along the electrode thickness direction. Moreover, orthogonal experimental design method is also developed and applied to identify the optimal parameter ranges, and the graded porosity is found to be the dominant factor enhancing hydrogen production, while the graded Ni composition is the primary parameter governing the maximum thermal stress. Synergistic optimization of porosity and Ni composition gradients achieves a 24.9% increase in the hydrogen production with a 10.0% reduction in the maximum thermal stress, demonstrating their critical role in concurrently boosting SOEC performance and mechanical durability.