Volume 46: Energy Transitions toward Carbon Neutrality: Part IX

Three-dimensional numerical investigation on the transient response characteristics of DIR-SOFC during increasing electrical load process Bohan Li, Chaoyang Wang, Junjie Yan

Abstract

Solid oxide fuel cell (SOFC) is a promising power technology with clean, high efficiency, and exceptionally high fuel flexibility. This research established and experimentally verified a 3D-dynamic model of a planar direct internal reforming (DIR) SOFC. Based on the developed model, the 500-second dynamic response characteristics of the cell fueled by pure hydrogen or 0.3 pre-reformed syngas were investigated after increasing the power density by 20%. The results show that the power density response of the cell, whether hydrogen or syngas-fueled, can be divided into a concentration-dominated fast-response stage with a subsequent temperature-dominated slow-response stage. The fast-response stage is finished in a few seconds, while the slow-response stage takes hundreds of seconds to stabilize. When the initial power density (P0) is relatively low (P0=1500W/m2), the changes in the fast-response stage account for more than 93% of the whole process, indicating that the power density can be stabilized quickly. As the initial power density increases, the proportion of power density change in the slow-response stage gradually increases and reaches more than 50%. When P0=4000W/m2, the power density of the cell fueled by hydrogen or syngas increases by 400 W/m2 and 520 W/m2, respectively, in the slow-response stage, corresponding to 50% and 65% of the whole process.

Keywords Solid oxide fuel cell, 3D dynamic model, transient performance, direct internal reforming, DIR-SOFC