This paper conducts a multiscale parametric study of temperature and composition effects on the transport phenomenon of a solid oxide fuel cell (SOFC). The molecular dynamics technique was employed to study the transport phenomenon of the solid electrolyte, which is made of yttria-stabilized zirconia. The influences of Y2O3 concentration and various operation temperatures on the SOFC were studied. Simulation results show that there exists an optimal concentration of 8mol% of Y2O3 in the composition for oxygen transport. Also higher operation temperature promotes the oxygen ion-hopping process that increases the ionic conductivity. A macroscale parametric study was also conducted in this paper to validate the influence of the temperature uniformity in the solid electrolyte by employing the computational fluid dynamics technique. The temperature distribution maps of a single-cell planar SOFC with coflow, counterflow and cross-flow channel designs are presented. The results conclude that the coflow configuration is the best design of the three.

Issue Section:
Research Papers
Keywords:
solid oxide fuel cells, solid electrolytes, temperature distribution, molecular dynamics method, yttrium compounds, oxygen, transport processes, ionic conductivity, channel flow, computational fluid dynamics
Topics:
Computational fluid dynamics, Diffusion (Physics), Electrolytes, Ionic conductivity, Oxygen, Simulation results, Solid electrolytes, Solid oxide fuel cells, Temperature, Temperature distribution, Transport phenomena, Ions, Simulation, Cross-flow, Zirconium, Design, Molecular dynamics, Displacement, Temperature uniformity
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