An experimental study on the motion, deformation and electrical charging of water drops falling in oil in the presence of high voltage D.C. electric field

Abstract The motion, deformation and electrical charging of conducting water drops falling in an insulating liquid subjected to various electric fields strength were studied experimentally. The drop motion was recorded contentiously by high speed camera and their responses to deformation under the influence of electric field were digitally extracted by image processing of the sequential frames. Two parameters were defined for describing the deviation and deformation of the drops under the electric forces. Outcomes depicted that the deviation of the drops from the vertical line would be increased by adding to the applied electrical potential as well as reduction of drop size. Moreover, regarding to deformation diagram, the results revealed a dissimilar deformation manner between large and small drops, which can be helpful in describing the drop-drop electro coalescence phenomena and in design of electrically driven droplet-based systems

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