Theoretical prediction of electric field‐enhanced coalescence of spherical drops

Abstract

AbstractA fundamental study of drop collision, coalescence and growth induced by combined effects of gravitational and electrostatic forces is presented. The focus is on the enhancement of rates of collision and growth of spherical, conducting drops bearing zero net charge in dilute, homogeneous dispersions by an external electric field. By completely accounting for hydrodynamic and electrostatic interactions, a trajectory analysis is used to follow the relative motion of two drops equation is then solved to predict the evolution in time of the size distribution and the average size of drops. The results show that the rates of drop collision and growth can be increased significantly by applying an electric field, in accord with fundamental experiments and patents on electrocoalescence. The enhancement of drop collision and coalescence is especially pronounced when the imposed electric field acts horizontally, that is, in a direction perpendicular to gravity.