Deformation of magnetosensitive emulsion microdroplets in magnetic and electric fields

Abstract

A magnetosensitive emulsion comprising an ensemble of nonmagnetic oil droplets suspended in a kerosene-based magnetic fluid is studied. It is found that the droplets of such an emulsion are deformed in both magnetic and electric fields. The character of microdroplet deformation in the electric field depends on the field frequency: at low frequencies, the droplets are flattened; at high frequencies, the droplets are stretched along the force lines of the field. It is established that the deformation caused by the electric field can be compensated for by the imposition of an additional magnetic field, and the conditions of this compensation are determined. It is revealed that, under the action of a magnetic field directed normal to a thin layer of the emulsion, the drop- lets "split" into branched structures. The action of a similarly directed alternating electric field leads to the trans- formation of the droplets into tori followed by their rupture. It is concluded that the structure of the emulsion can be efficiently controlled using the combined action of magnetic and electric fields.