(229g) CFD Based Design of Planar SOFC for Improvement in Performance

Solid oxide fuel cell (SOFC) is one of the possible solutions to the challenge posed by our current energy requirement, the core competency of which is based on efficiency and clean energy conversion. In order to achieve wide spread acceptance, the technology has to perform reliably well over a long period of time. Long term performance is governed by materials of construction and design of the cell as well as the environment under which it is operated. SOFC performances are affected by different types of losses such as activation, ohmic and concentration. The concentration losses depend upon the distribution of fuel and oxidant over the cell active area. The flow distribution in any fuel cell is ensured by designing appropriate flow-configuration. The present work aims to investigate the flow uniformity and mass transport losses in SOFC and the role of flow geometry on improving performance of the unit. The preliminary design consists of an outlet manifold, channel feeding the active area region and an inlet manifold. The simulation of the entire model on the computational platform is proved to be counter-productive. So, the geometry is subdivided into three parts (inlet manifold, straight channel and outlet manifold) and the flow field is sequentially simulated. Pressure drop in the channel is determined assuming the flow to be fully developed and laminar in the channel, which is valid owing to the large length to hydraulic diameter (l/D >> 1) ratio for each channel. The simulation in the other two decomposed geometries is obtained from  numerical simulation. Different types of manifold modifications are used in order to achieve better flow uniformity. Finally, the design which results in to the most uniform flow distribution in the active area is selected for fabrication and performance testing.  The electrochemical performance is observed to enhance by ~15% using the modified design of the manifolds.