Mass transport in gas channels of electrochemical cells with a solid-oxide electrolyte: Allowing for the electrode reaction rates in numerical calculations

Abstract

The concentration fields, Nusselt number distributions along the electrode, and ratios of concentrations of electrochemically active components at the entrance into and exit out of an electrochemical cell are determined by numerical integration of the convective-diffusion equation for a broad range of rate constants of electrode reactions, Peclet numbers, and geometrical parameters of channels. Three regions of parameter values are revealed. At low reaction rates (K l 20), it is completely determined by the diffusion in the gas phase; and in the intermediate region of values of K l it is necessary to allow for both the diffusion processes and the electrode reactions.