Electrocoalescence of water drop pairs in oil

In an emulsion in an ac field, charges induced on the drops will make adjacent drops align with the field and attract each other. Coalescence of water droplet pairs in naphtenic oil subjected to an ac electric field of varying frequency, shape and amplitude was studied with high-speed optical and electrical techniques. The coalescence is a very rapid process. At the moment of drop impact a current pulse was observed. Different possible coalescence mechanisms are suggested and discussed.