Design and optimization of the external manifold with a spider-web-inspired perforated sheet for solid oxide fuel cells

Abstract

The gas flow distribution in solid oxide fuel cell (SOFC) stacks has a significant impact on the electro-thermal-mass transport performance and safety. In this study, an external manifold structure incorporating a spider-web-inspired perforated sheet is designed for a planar SOFC stack. Numerical simulations are performed to investigate the effects of key geometric parameters (the angle of the sector-shaped holes (θ1), manifold depth (H), and posterior diameter of the flared inlet tube (Doutlet)) on flow uniformity and pressure drop. Compared with a configuration without a perforated sheet, the non-uniformity index (NUI) decreases from 2.26% to 0.16% when θ1 =2°. To obtain the optimal geometric configuration, dimensionless treatment is applied to θ1, Doutlet, and H. The Taguchi method is used to derive the optimal parameter combination. The NUI of the SOFC stack after optimization is further reduced to 0.0658%, and the stack pressure drop decreases from 561 Pa to 412 Pa. Compared with a conventional round hole perforated sheet, the stack employing the spider-web perforated sheet achieves a more uniform gas flow rate to each cell, resulting in further enhancement in overall flow distribution.