Solid Oxide Fuel Cell Performance With Cross-Flow Roughness

To increase power per unit volume in solid oxide fuel cells (SOFCs), the mono-block-layer-built SOFC used an innovative shape to increase active surface area. The objective of this study is to increase reaction area in a planar fuel cell while avoiding the negative aspects of large thermal gradients, Ohmic loss, and concentration loss by using a common heat transfer enhancement technique (i.e., cross-flow roughness). A numerical model developed with the commercial software FLUENT was used to compare the effects of four rib geometries, such as rib shape, rib spacing, and rib area, on performance under conditions simulating the flow in a typical SOFC. Cross-flow roughness geometries had minimal effect on mixing but increased active area of the cells, resulting in improved performance while maintaining similar thermal gradients and current path lengths to the standard planar fuel cell geometry.