INFLUENCE OF INTERCONNECT-CHANNEL SHAPE ON HEAT AND MASS TRANSFER IN ANODE-SUPPORTED PLANAR SOLID OXIDE FUEL CELLS

摘要

Heat and mass transfer characteristics of planar anode-supported solid-oxide fuel cell (SOFC) module, with bi-polar plate interconnect channels of different shapes are computationally simulated. The electrochemistry is modeled by a uniform supply of volatile species (80% hydrogen + 20% water) and oxidant (20% oxygen + 80% nitrogen) to the electrolyte surface with a constant electrochemical reaction rate. Interconnect flow channels of rectangular, trapezoidal and triangular cross sections for both fuel and oxidant supply are considered. The governing three-dimensional partial differential equations for mass, momentum, energy, and species transport along with those for electrochemical kinetics, where the homogeneous porous-layer flow is in thermal equilibrium with the solid matrix, are coupled with the electrochemical reaction rate to properly account for the flow-duct and anode-/cathode-interface heat and mass transfer. The results highlight the effects of flow-duct shape on the lateral temperature and species (H_2, H_2O and O_2) distributions as well as the frictional pressure drop and heat transfer coefficient. It is seen that a relatively shallow rectangular duct offers better heat and mass transfer performance to effect improved thermal management of planar SOFCs.