Numerical investigation of electrostatically enhanced coalescence of two drops in a flow field

When an electric field is applied to an emulsion where a conductive fluid is dispersed in an insulating fluid, attractive forces will arise between the drops due to polarization. The drops then tend to coalesce more readily than when no electric field is applied. This phenomenon, often denoted electrocoalescence, is employed for instance to enhance the separation of water from oil extracted from offshore wells. In this work, we employ detailed numerical simulations to study the influence of external flow and electric field on the head-on collision between two drops.