Direct Numerical Simulation (DNS) is used to examine the significance of electroconvective effects on the response of drops immersed in electric fields. The electric Reynolds number, defined as the ratio between the charge relaxation time due to Ohmic conduction and the time scale associated with charge convection, is used to quantify the strength of electroconvective effects. The computations show that the convection of electrical charges results in a weakening of the oblate deformation observed for drops less conductive than the suspending fluid and a strengthening in the prolate deformation of drops more conductive than the suspending fluid. In addition, DNS is also used to examine how the convection of electrical charges modifies the drop-to-drop interaction. When two or more drops are close enough, the presence of an electric field leads to a complex interaction that can result in either drop aggregation or a repulsion force between the drops depending on the dielectric properties and strength of the electric field. Charge convection strengthens the repulsion when the electrical conductivity ratio is greater than the dielectric permittivity ratio, whereas it reinforces attraction when the dielectric permittivity ratio is higher than the electrical conductivity ratio.

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