Articles techniques et présentations

Dr Lathapriya1, Dr. Mishma S Stanislaus1, Dr Anand M Shivapuji2, Prof S Dasappa3

1 Research Scientist; 2 Senior Research Scientist; 3 Professor and Chair Interdisciplinary Center for Energy Research Indian Institute of Science; Bangalore - 560012

The motivation for this study arises from the growing interest in clean and efficient energy conversion technologies. Solid Oxide Fuel Cells (SOFCs) have gained prominence due to their ability to directly convert a range of fuels into electricity with high conversion efficiency and low emissions. The ability to tolerate substantially high levels of contaminants is a critical selling point for SOFCs. This study focuses on modeling and analysis of an SOFC of flat tubular cell geometry with specific focus on comparison between air and oxygen as cathode fuels with two different bio-syngas compositions being used as the anode gas. COMSOL Multiphysics is employed in this study owing to its capability of integrating various physical phenomena such as mass transport, charge-transfer kinetics, flow distribution in gas channels/porous electrodes, electrochemical reactions and heat transfer within a single simulation platform. This integrated approach is essential for accurately capturing the intricate interactions occurring within a SOFC system. By comparing the performance of SOFCs operated with air and oxygen on cathodes, it is observed that syngas/producer gas operated with oxygen as cathode fuel resulted in a maximum current and power values than air as cathode fuel. The current and power values of syngas and producer gas fueled SOFCs in an oxygen environment are 5724 A/m2 and 1789 W/m2 (syngas) and 3737 A/m2 and 1369 W/cm2 (producer gas), respectively. Whereas, in the case of air environment, the current and power values of syngas and producer gas fueled SOFCs are 3625 A/m2 and 1365 W/m2 (syngas) and 2858 A/m2 and 1174 W/cm2 (producer gas), respectively. This is consistent considering that with air as the Oxidizing media, the cathode side experience dilution effects due to Nitrogen. Polarization traces showed negligible activation loss, ohmic losses and very small mass transport losses. Moreover, the mass distribution of each species of syngas and producer gas along with velocity and pressure profile is also simulated to understand the properties of modelled flat tubular SOFC. The distribution of CO, CO2, CH4 and H2 is higher near the anode inlet and very low near the anode outlet which shows that the current density is decreasing along the flow channel due to the depletion of fuels. The current study contributes to the understanding of syngas-fueled and producer gas-fueled SOFCs and the influence of cathode fuel selection on their performance.