Computational Fluid Dynamic Analysis of a Seal-Less Solid Oxide Fuel Cell Stack

Abstract

Combined heat and power generation systems accommodating intermediate temperature (600–800°C) solid oxide fuel cell (SOFC) modules have been developed by Mitsubishi Materials Corporation and The Kansai Electric Power Co., Inc. High overall efficiency system units are designed in such a way that their output power can be modularized by altering the number of stacks inside the SOFC modules. The seal-less design concept is adopted to build generic stacks made up of stainless steel separators and disk-type planar electrolyte-supported cells. Innovative stack design together with its precise integration with the hot balance of plant components inside the SOFC module requires a number of design iterations supported by carefully planned experiments. In order to achieve improved levels of efficiency and reliability via optimum number of iterative cycles, we believe that the computational techniques offer significant advantages. In this work, a commercial computational fluid dynamics code is employed for solving the conservation of mass, momentum, and energy equations with an additional electrochemical submodel to simulate the coupled multiphysics processes in a generic SOFC stack. This approach proved to be effective in providing necessary guidance for identifying problem areas in the stack design and estimating the stack performance via less expensive numerical experiments. The results of the computational model are also compared with data obtained by experimental measurements.