Transient solution for droplet deformation under electric fields.

A transient analysis to quantify droplet deformation under DC electric fields is presented. The full Taylor-Melcher leaky dielectric model is employed where the charge relaxation time is considered to be finite. The droplet is assumed to be spheroidal in shape for all times. The main result is an ODE governing the evolution of the droplet aspect ratio. The model is validated by extensively comparing predicted deformation with both previous theoretical and numerical studies, and with experimental data. Furthermore, the effects of parameters and stresses on deformation characteristics are systematically analyzed taking advantage of the explicit formulas on their contributions. The theoretical framework can be extended to study similar problems, e.g., vesicle electrodeformation and relaxation.

[1]  Howard A. Stone,et al.  Electrohydrodynamic deformation and interaction of drop pairs , 1998, Journal of Fluid Mechanics.

[2]  S. Kanazawa,et al.  Emulsification and Demulsification Processes in Liquid–Liquid System by Electrostatic Atomization Technique , 2008, IEEE Transactions on Industry Applications.

[3]  George M. Homsy,et al.  Axisymmetric deformation and stability of a viscous drop in a steady electric field , 2007, Journal of Fluid Mechanics.

[4]  Petia M. Vlahovska,et al.  Electrohydrodynamics of drops in strong uniform dc electric fields , 2010 .

[5]  O. Vizika,et al.  The electrohydrodynamic deformation of drops suspended in liquids in steady and oscillatory electric fields , 1992, Journal of Fluid Mechanics.

[6]  H. Stone,et al.  Selective spreading and jetting of electrically driven dielectric films. , 2011, Physical review letters.

[7]  Sonja Krause,et al.  Droplet deformation in dc electric fields: the extended leaky dielectric model. , 2005, Langmuir : the ACS journal of surfaces and colloids.

[8]  Geoffrey Ingram Taylor,et al.  Disintegration of water drops in an electric field , 1964, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[9]  Y. Mori,et al.  Behavior of oblately deformed droplets in an immiscible dielectric liquid under a steady and uniform electric field , 2006 .

[10]  G. Dassios,et al.  Generalized eigenfunctions and complete semiseparable solutions for Stokes flow in spheroidal coordinates , 1994 .

[11]  Michael J. Miksis,et al.  Shape of a drop in an electric field , 1981 .

[12]  T. Tsukada,et al.  Finite Element Analysis of Electrohydrodynamic Time-Dependent Deformation of Dielectric Drop under Uniform DC Electric Field , 2000 .

[13]  S. G. Mason,et al.  Particle behaviour in shear and electric fields I. Deformation and burst of fluid drops , 1962, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[14]  Osman A. Basaran,et al.  Small‐scale free surface flows with breakup: Drop formation and emerging applications , 2002 .

[15]  J. R. Melcher,et al.  Electrohydrodynamics: A Review of the Role of Interfacial Shear Stresses , 1969 .

[16]  O. O. Ajayi A note on Taylor’s electrohydrodynamic theory , 1978, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[17]  Timothy C. Scott,et al.  A computational analysis of electrohydrodynamics of a leaky dielectric drop in an electric field , 1996, Journal of Fluid Mechanics.

[18]  B. M. Fulk MATH , 1992 .

[19]  James Q. Feng Electrohydrodynamic behaviour of a drop subjected to a steady uniform electric field at finite electric Reynolds number , 1999, Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[20]  G. Taylor Studies in electrohydrodynamics. I. The circulation produced in a drop by an electric field , 1966, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[21]  A. Castellanos,et al.  Nonlinear electrohydrodynamics of free surfaces , 1998 .

[22]  D. Saville ELECTROHYDRODYNAMICS:The Taylor-Melcher Leaky Dielectric Model , 1997 .

[23]  J. Sherwood,et al.  Breakup of fluid droplets in electric and magnetic fields , 1988, Journal of Fluid Mechanics.

[24]  N. Dubash,et al.  Behaviour of a conducting drop in a highly viscous fluid subject to an electric field , 2007, Journal of Fluid Mechanics.

[25]  J. Zahn,et al.  A general analysis for the electrohydrodynamic instability of stratified immiscible fluids , 2011, Journal of Fluid Mechanics.

[26]  R. Clark,et al.  Electrohydrodynamic atomization: a versatile process for preparing materials for biomedical applications , 2008, Journal of biomaterials science. Polymer edition.

[27]  R. G. Cox,et al.  Electrohydrodynamic deformation and bursts of liquid drops , 1971, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[28]  Seung-Man Yang,et al.  Deformation and breakup of Newtonian and non-Newtonian conducting drops in an electric field , 2000, Journal of Fluid Mechanics.