Electro-thermo-convection in a planar layer of dielectric liquid subjected to electrohydrodynamic conduction and thermal gradient

In this work, we numerically investigate the electro-thermal-convection phenomena induced by the simultaneous action of electrohydrodynamic conduction and a thermal gradient between two parallel plates. The coupled set of governing equations including the charge conservation equations and the Poisson equation for the electric potential are incorporated into the finite-volume framework of OpenFOAM. The influence of temperature on the physical properties of dielectric liquid has been considered. The effect of dielectric force and Coulomb force on the thermal convection has been investigated. Results show that the dielectric force advances the onset of Rayleigh-Bénard convection (RBC) and leads to the instability of RBC flow with the low Rayleigh number.