Modelling of novel porous inserted micro-tubular, single-chamber solid oxide fuel cells (MT-SC-SOFCs)

In order to improve the performance of a micro-tubular, single-chamber solid oxide fuel cell (MT-SC-SOFC), a porous material was inserted in the free space between the cell and the gas chamber. Four different cases were studied, namely: case 1) bare gas-chamber, i.e., with no porous inserts, case 2) completely filled porous gas-chamber, case 3) half filled porous gas-chamber, and case 4) partially filled porous gas-chamber ensuring free equal volume for gas flow around both electrodes. The three porous arrangements were used to reduce the un-utilized gas mixture that would otherwise bypass the cell. The results of porous gas-chamber (i.e., cases 2-4) were compared with the bare gas-chamber (i.e., case 1). It is concluded that case 4 appears to be the best amongst other investigated cases, as it improves the power output by 16.96% as compared to case 1. The best power output obtained in case 4 is due to better gas management around both electrodes which enhances the convective transport within the porous electrodes. The lower concentration polarization in case 4 is believed to be the enhancement factor that was limiting the cell performance in case 1. (C) 2011 Elsevier B.V. All rights reserved