Numerical investigation of non-uniformity in a tubular solid oxide co-electrolysis stack: From multi-physics modeling to optimization strategy

A 10-cell tubular solid oxide electrolysis cell (SOEC) stack for CO₂/H₂O co-electrolysis is fabricated and analyzed through a validated three-dimensional multiphysics model. The simulation reveals pronounced intra-cell and inter-cell thermal non-uniformities, encompassing an inlet temperature gradient of 26.70 K/cm and a cell-to-cell thermal standard deviation of 14.89. To mitigate these issues, two novel anode-side blowing strategies, stepped and front blowing, are proposed and evaluated. The stepped blowing configuration reduces the maximum intra-cell temperature gradient by 35.73% and enhances overall electrochemical performance by 21.64% at an operating voltage of 15 V. The front blowing arrangement lowers the inter-cell thermal standard deviation by 54.73% while improving stack performance by 18.83%. As indicated by the above-mentioned results, tailored anode flow management can effectively alleviate thermal imbalances in tubular SOEC stacks, thereby offering a practical and scalable pathway toward more efficient and durable co-electrolysis systems for power-to-X applications.