Numerical modeling for 3D vortices patterns of electroconvective flow developing in shear flow

Abstract

In this study, using direct numerical modeling, we investigate the electroconvective flow developing on the surface of an ion-exchange membrane surface in the high applied voltage condition. The modeling is obtained by solving the system of Poisson–Nernst–Planck–Navier–Stokes equations in a direct and coupled manner on the OpenFOAM platform. We report simulation results proving the dependence of the flow's pattern on the applied voltage and the mechanism behind the formation of vortices at high electric fields. For the first time, different types of vortices and the concurrent appearance of helical and unidirectional vortices are studied. The role of the vortices on the distribution of ions and the electric current is clarified to explain the over-limiting current phenomenon. This work contributes a useful OpenFOAM solver integration tool for modeling electrochemical problems.