Numerical Study of Electroconvective Instability of Binary Electrolyte in a Cell with Plane Parallel Electrodes

Abstract

Electroconvective instability of a binary electrolyte in a cell with plane parallel electrodes is studied using a numerical method. When a direct current is passed through the cell, a space charge and an electrical force acting upon the solution form under certain conditions. If the electric force density reaches a critical value, convective instability emerges in the cell, leading to the formation of nonequilibrium dissipative structures similar to Rayleigh–Benard cells in a nonuniformly heated liquid. The critical parameter γcrit, at which instability emerges in the system, is determined. Dependences of γcrit on the ratio between the diffusion coefficients for electrolyte cations and anions and on the current passed through solution are determined.