Thermo‐electrohydrodynamic convection in a differentially heated shell with electric central force field

Abstract

AbstractThermo‐electrohydrodynamic convection is investigated in a shell with central force field to investigate convective pattern formation for potential heat transfer application and small scaled laboratory experiments e.g. the modelling of convection in planetary interiors or atmospheres. To induce TEHD convection the outer and inner shells are heated at different temperatures whereas an alternating electric potential is applied between both shells. The observation of the convective pattern formation suggest that dielectric fluids have a significant response to thermal and electrical forcing. The observed patterns ranged from quasi‐stationary convective modes in azimuthal direction to shape and mode amplitude vacillations with mode merging and separation that are classified into three regimes. The heat transfer was evaluated by the Nusselt number and showed an increase in heat transfer with electric forcing. However, the results indicate a much smaller heat transfer when compared to natural convection.