References

Mechanical Sciences

Mech. Sci.

2191-916X

Copernicus Publications

Göttingen, Germany

10.5194/ms-4-333-2013

Experimental investigation of water droplets' behavior in dielectric medium: the effect of an applied D.C. electric field

Bararnia

¹ Ganji

D. D.

Department of Mechanical Engineering, Babol University of Technology, Babol, Iran

11 10 2013

4 2 333 344

2013

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

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In this article, the behavior of water droplets which are suspended in silicon oil is qualitatively investigated and some phenomena such as liquid's burst are reported. The movement of droplet in perpendicular line is considered while many studies have considered small droplets fluctuating between two horizontal electrodes. Additionally any deformation caused by increasing voltage was observed from start to finish until short contact occurred. As can be seen two oppositely charged drops contacting each other do not necessarily result in coalescence. Repelling can be expected occasionally. By increasing the voltage, the droplets, which spread through the domain due to frequent breakups, tend to gather in a certain line.

References 1

Ahn, K., Agresti, J., Chong, H., Marquez, M., and Weitz, D. A.: Electrocoalescence of drops synchronized by size-dependent flow in microfluidic channels, Appl. Phys. Lett., 88, 264105, <a href="http://dx.doi.org/10.1063/1.2218058">https://doi.org/10.1063/1.2218058</a>, 2006.

Aldaeus, F., Lin, Y., Amberg, G., and Roeraade, J.: Multi-step dielectrophoresis for separation of particles, J. Chromatogr. A, 1131, 261–266, 2006.

Allan, R. S. and Mason, S. G.: Particle behavior in shear and electric fields; I:deformation and burst of fluid drops, Proc. Roy. Soc. Lond. A, 267, 45–61, 1962.

Bailey, A. G.: Electrostatic spraying of liquids, Wiley, New York, 1988, dynamic processes in electrospraying, J. Aerosol Sci., 30 (Suppl. 1), 549–550, 1999.

Baygents, J. C. and Saville, D. A.: The circulation produced in a drop by an electric field: a high field strength electrokinetic model, in: Drops and Bubbles: Third Int. Colloq., edited by: Wang, T. G., American Institute of Physics, 7–17, 1989.

Chiesa, M., Melheim, J. A., Pedersen, A., Ingebrigtsen, S., and Berg, G.: Forces acting on water droplets falling in oil under the influence of an electric field: numerical predictions versus experimental observations, Eur. J. Mech. B-Fluid., 24, 717–732, 2005.

Dong, W., Li, R. Y., Yu, H. L., and Yan, Y. Y.: An investigation of behaviors of a single bubble in a uniform electric field, Exp. Therm. Fluid Sci., 30, 579–586, 2006.

Eow, J. S. and Ghadiri, M.: Motion, deformation and break-up of aqueous drops in oils under high electric field strengths, Chem. Eng. Process., 42, 259–272, 2003a.

Eow, J. S. and Ghadiri, M.: Drop-Drop coalescence in an electric field: the effects of applied electric field and electrode geometry, Colloid. Surface. A, 219, 253–279, 2003b.

Eow, J. S., Ghadiri, M., Sharif, A. O., and Williams, T. J.: Electrostatic enhancement of coalescence of water droplets in oil: a review of the current understanding, Chem. Eng. J., 84, 173–192, 2001.

Feng, J. Q. and Scott, T. C.: A computational analysis of electrohydrodynamics of a leaky dielectric drop in an electric field, J. Fluid Mech., 311, 289–326, 1966.

Ha, J. W. and Yang, S. M.: Deformation and break-up of Newtonian and non-newtonian conducting drops in an electric field, J. Fluid Mech., 405, 131–156, 2000.

Hase, M., Watanabe, S. N., and Yoshikawa, K.: Rhythmic motion of a droplet under a dc electric field, Phy. Rev. E., 74, 046301, <a href="http://dx.doi.org/10.1103/PhysRevE.74.046301">https://doi.org/10.1103/PhysRevE.74.046301</a>, 2006.

Hokmabad, B. V., Sadri, B., Charan, M. R., and Esmaeilzadeh, E.: An experimental investigation on hydrodynamics of charged water droplets in dielectric liquid medium in the presence of electric field, Colloid. Surface. A, 401, 17–28, 2012.

Khorshidi, B., Jalaal, M., Esmaeilzadeh, E., and Mohammadi, F.: Characteristics of deformation and electrical charging of large water drops immersed in an insulating liquid on electrode surface, Colloid Interface Sci., 352, 211–220, 2010.

Pikal, M. J.: The role of electroosmotic flow in transdermal iontophoresis, Advance Drug Delivery, Reviews, 46, 281–305, 2001.

Ristenpart, W. D., Bird, J. C., Belmonte, A., Dollar, F., and Stone, H. A.: Non-coalescence of oppositely charged drops, Nature, 461, 377–380, 2009.

Sherwood, J. D.: Breakup of fluid droplets in electric and magnetic fields, J. Fluid Mech., 188, 133–146, 1988.

Taylor, G. L.: Proc. Studies in electrohydrodynamics; I: the circulation produced in a drop by an electric field, Roy. Soc. A, 291, 159–167, 1966.

Torza, S., Cox, R. G., and Mason, S. G.: Electrohydrodynamic deformation and burst of liquid drops, Philos. Trans. R. Soc. Lond. A, 269, 295–319, 1971.

Vizika, O. and Saville, D. A.: The electrohydrodynamic deformation of drops suspended in liquids in steady and oscillatory electric fields, J. Fluid Mech., 239, 1–21, 1992.