Flow uniformity analysis and optimization of a 60-cell external manifold solid oxide cell stack with bottom-accesses

In order to enhance the integration of the SOFC stack module and facilitate the assembly of the external manifold stack, a bottom-access structure stack was developed. Computational fluid dynamics (CFD) techniques were employed to investigate the gas distribution of the stack. Multiple parameters, such as geometrical parameters, manifold structures, and buffer chambers were optimized to improve flow distribution uniformity. The results indicated that the introduction of guide plates and distributors in the manifold helped to prevent vortex generation, which led to an increase in the mass flow rate of cells near the inlet. The uniformity of flow distribution can be greatly improved by increasing the buffer chamber height, but when the buffer chamber height is excessive, it has the opposite effect. The depth of the manifold only has a limited impact on the flow distribution. Ultimately, the optimal structure was found to be the manifold with guide plates and buffer chambers, which reduced flow non-uniformity from 8.4% to 1.4%. These findings provide reliable guidance for the improvement of flow distribution in the bottom-access stack.