On flow uniformity in various interconnects and its influence to cell performance of planar SOFC

Abstract

This paper investigates flow uniformity in various interconnects and its influence to cell performance of a planar SOFC. A transparent hydraulic platform was used to measure flow uniformity in different rib-channel modules of interconnects. Several 3D numerical models implemented by CFD-RC packages were established to first simulate these hydraulic experiments and then used to evaluate the cell performance of a single-cell stack using different designs of interconnects with different flow uniformity over a wide range of a hydraulic Reynolds number ( Re) based on a hydraulic diameter of rib-channels. Numerical flow data are found in good agreement with experimental results. It is proposed that a new design, using simple small guide vanes equally spaced around the feed header of the double-inlet/single-outlet module, can effectively improve the degree of flow uniformity in interconnects resulting in 11% increase of the peak power density (PPD) which can be further increased when applying a Ni-mesh on anode. Numerical analyses demonstrate a strong influence of Re on cell performance, of which appropriate ranges of Re in both anode and cathode sides are identified for achieving a reasonably good PPD while remaining an economic fuel utilization rate and having less temperature variations in the single-cell stack.