Entropy Generation Minimization for the Optimal Design of the Fluid Distribution System in a Circular MCFC

Abstract

In this paper, the prototype of a circular Molten Carbonate Fuel Cell (MCFC) built in the laboratories of Fabbricazioni Nucleari (FN) is analyzed using a tridimensional computational fluid dynamic (CFD) model. This model considers heat, mass and current transfer as well as chemical and electrochemical reactions. The results show that some inhomogeneous distributions in the reactants, causing non optimal use of the reactant surfaces, take place. An effective way to improve the distribution in current density consists in tracing tree shaped channels on the surface onto the distribution porous medium. A preliminary study on the effectiveness of such technical solution is investigated considering a network model of the fluid flow in the porous medium and the channels. Then the optimal shape of distribution channels is investigated considering some geometrical parameters identifying their topology and length as the independent design variables. Minimum entropy generation is considered as the objective function.The results show that significant improvements in the current density can be achieved.