A new procedure for rapid convergence in numerical performance calculations of electrochemical cells

Abstract

This paper introduces a novel coupled region-to-region numerical procedure for electric field potential calculations. A conventional segregated scheme is also introduced to illustrate the coupling issues that exist in performance calculations in electrochemical devices. Numerical simulations are conducted for a solid oxide cell operating in both fuel cell and electrolysis modes. The cell performance is predicted with both segregated and coupled methods. A comparison between the coupled and segregated schemes shows that the former greatly outperforms the latter, reducing convergence times (from 5000 to 300 iterations) and improving stability. A smaller coupling coefficient contributes to the convergence as well, however, less markedly. The coupled region-to-region approach may readily be applied to numerous other scenarios, e.g., heat transfer problems between multiple phases and regions.