One type of hydrodynamic instability in joule heating of a fluid near an ion-selective surface

Abstract

The stability of the equilibrium state of an electrolyte in a horizontal microgap between two ionselective surfaces in an electric field is studied with the Joule heating of the fluid taken into account. It is established that the Joule heating can lead to instability at the potential differences, which are several times smaller than those in the isothermal case. The effects of microscale thermal instability differ from the Rayleigh–Benard thermal convection: the destabilization occurs upon heating in the upper part of the gap.