Fuel and Combustion

Fuel and Combustion

Modeling a Planar Solid Oxide Fuel Cell for Combined Heat and Power Systems

Authors
pezhman Kazempoor
Fattolah Ommi
Faculty of Engineering, Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran
Abstract

The paper presents a detailed solid oxide fuel cell (SOFC) model that is specifically developed for the performance evaluation of planar SOFC stacks in combined heat and power (CHP) systems. The developed model includes the mass, momentum, thermal and electrochemical analysis, as well as the kinetic models of hydrocarbon reactions. The electrochemical model includes a complete evaluation of ohmic, activation and diffusion polarisations. To increase the accuracy of the model; methane reforming and water-gas shift reactions, several layers of temperature, radiation heat transfer model and material temperature dependent property are also applied to the model. The model is also validated with available numerical and experimental data for a high temperature SOFC with internal reforming, showing the capacity to accurately predict its operating conditions. Finally, sensitivity analyses on fuel utilization factor and on air excess ratio are performed to investigate the effects of different key parameters.
Keywords
Solid oxide fuel cell
Control volume
System modeling
Voltage polarization
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