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Published on: April 5, 2022
Electrocoalescence: effects of DC electric fields on coalescence of drops at planar interfaces
Hamarz Aryafar1, H Pirouz Kavehpour
1Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, California 90095, USA.
Abstract:
The current work attempts to explore the role of DC electric fields on neutrally charged coalescing conductive droplets. The droplet is isolated inside of silicone oil and allowed to coalesce into a planar bulk of its own fluid under the influence of the electric field. The effect of this additional field in conjunction with the effects of other physical properties of the liquids including viscosity and interfacial tension are studied with the use of a digital high-speed camera. By scaling the electric field appropriately, distinct regions of behavior are defined in which electrically induced partial coalescence occurs within a viscous environment. Furthermore, it is shown that droplet size and field strength will determine if the processes of coalescence leads to either jet formation or Taylor cone formation on the planar interface for sufficiently strong electric fields.
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