Skip to main content
SpringerLink
Log in

Droplet motion in an electrohydrodynamic fine spray

  • Originals
  • Published:
Experiments in Fluids Aims and scope Submit manuscript

Abstract

The results of a combined experimental and numerical study on droplet behavior within an electrohydrodynamic fine spray are presented. The fine spray exists in the transition region between the multiple cone-jet and rim emission spray modes. Experiments were conducted specifically to characterize the motion of droplets within the spray. Light-sheet visualizations and measurements of droplet speed and velocity using laser-based, single-particle counters were obtained. Additionally, a numerical simulation of the droplet motion within the spray was made and compared to the experimental results. The electrohydrodynamic fine spray of ethanol droplets (∼ 1 to 40 μm diameter) was generated using a typical capillary-plate configuration, with a capillary tip electric field intensity of ∼ 106 V/m and a spray charge density of ∼70 C/m3. Acquired images of the spray revealed a zone of rapid expansion near the capillary followed by a more gradual expansion farther from the capillary. In situ laser-diagnostic measurements confirmed these observations. Measured droplet speeds decreased rapidly with increasing axial distance from the capillary, but then increased beyond the spray's axial mid-plane as a result of a change in the sign of the axial internal electric field. Droplet axial velocity components behaved similarly. The radial velocity components exhibited a maximum value off of the spray's centerline in the near-capillary region. Farther away from the capillary, they increased monotonically with increasing radial position. These trends identified the significant role that the radial internal electric field plays in spray expansion. The numerical simulation of the normal spray verified the inferred change in sign of the axial internal field and underscored the dominant contribution of the external electric field in the near-capillary region and of the internal electric field farther away.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Aerometrics Inc. (1987) Phase Doppler particle analyzer operations manual. Mountain View, CA

  • Bailey AG (1988) Electrostatic spraying of liquids. New York: Wiley

    Google Scholar 

  • Bachalo WD; Houser MJ (1984) Phase/Doppler spray analyzer for simultaneous measurements of droplet size and velocity distributions. Optical Eng 23: 583–590

    Google Scholar 

  • Balachandran W (1991) The present and future trends in electrostatic atomization of liquids. In: Atomization and sprays 2000 Workshop, eds N. Chigier, Gaithersburg, MD, pp. 123–139

  • Cloupeau M; Prunet-Foch B (1989) Electrostatic spraying of liquids in the cone-jet mode. J Electrostatics 22: 135–159

    Google Scholar 

  • Cloupeau M; Prunet-Foch B (1990) Electrostatic spraying of liquids: main functioning modes. J Electrostatics 25: 165–184

    Google Scholar 

  • Drozin VG (1955) The electrical dispersion of liquids as aerosols. J Col Sci 10: 158–164

    Google Scholar 

  • Dunn PF; Snarski SR (1991) Velocity component and diameter characteristics of droplets within two interacting electrohydrodynamic sprays. Phys Fluids A 3: 492–494

    Google Scholar 

  • Dunn PF; Snarski SR (1992) Droplet diameter, flux and total current measurements in an electrohydrodynamic spray. J Appl Phys 71: 80–84

    Google Scholar 

  • Dunn PF; Grace JM; Snarski S R (1994) The mixing of electricallycharged droplets between and within electrohydrodynamic fine sprays. J Aerosol Sci 25: 1213–1227

    Google Scholar 

  • Fernández de la Mora J; Loscertales IG (1994) The current emitted by highly conducting taylor cones. J Fluid Mech 260: 155–184

    Google Scholar 

  • Filippov AV (1991) Electrostatic deposition of inertially moving charged aerosol particles onto the earthed disk. J Electrostatics 26: 81–98

    Google Scholar 

  • Filippov AV (1992) Electrostatic deposition of a moving charged aerosol cloud onto a conducting sphere. J Aerosol Sci 23: 203–215

    Google Scholar 

  • Fletcher CAJ (1988) Computational techniques for fluid dynamics, Vol. 2. Berlin: Springer

    Google Scholar 

  • Fuchs NA (1964) The mechanics of aerosols. New York: Dover

    Google Scholar 

  • Gañán-Calvo AM; Lasheras JC; Dávila J; Barrero A (1994) The electrostatic spray emitted from an electrified conical meniscus. Aerosol Sci 25: 1121–1142

    Google Scholar 

  • Gilbert W (1600) De Magnete (p.55), translated by P.P. Mottelay. New York: Dover (1958), 89

  • Giles CR; Clements RM; Smy PR (1979) Flush probe studies of plasma flow over a flat plate theory J Phys D.: Appl Phys 12: 1685–1697

    Google Scholar 

  • Grace JM; Dunn PF (1992a) Laser light-sheet visualization of the spatial evolution and mixing of coherent droplet structures. Flow visualization VI, eds. Y. Tanida, H. Miyashiro, pp. 426–430, Berlin; Springer

    Google Scholar 

  • Grace JM; Dunn PF (1992b) Speed measurements in the developing region of an electrohydrodynamic spray using laser diagnostics. Exp Fluids 12: 261–269

    Google Scholar 

  • Grace JM (1993) Droplet motion and control in an electrohydrodynamic fine spray. Ph.D. Dissertation, University of Notre Dame, IN

    Google Scholar 

  • Grace JM; Dunn, PF (1994) Droplet motion in an elecrohydrodynamic fine spray. Conf. Proc. Int. Conf. Liquid Atom. and Spray Sys. Rouen, FR, 1002–1009

  • Grace JM; Marijnissen JCM (1994) A review of liquid atomization by electrical means. J Aerosol Sci 25: 1005–1019

    Google Scholar 

  • Harris MT; Sissons WG; Byers CH; Basaran OA (1994) Hydrous metal oxide ceramic precursor powders by electric field enhanced atomization. Conf Proc. Fourth Intrnl. Aerosol Conf., Los Angeles, CA, 49–50

  • Hayati I; Bailey AI; Tadros Th F (1987) Investigations into the mechanisms of electrohydrodynamic spraying of liquids, Parts I and II. J. Colloid Interface Sci 117: 205–230

    Google Scholar 

  • Hendricks CD (1962) Charged droplet experiments. J Colloid Interface Sci 17: 249–259

    Google Scholar 

  • Holve DJ; Annen KD (1984) Optical particle counting, sizing and velocimetry using intensity deconvolution. Opt Eng 23: 591–603 Insitec (1989) Manual for particle counter-sizer-velocimeter * PCSV. San Ramon, CA

    Google Scholar 

  • Jones AR; Thong KC (1971) The production of charged monodisperse fuel droplets by electrical dispersion. J Phys D: Appl. Phys 4: 1159–1166

    Google Scholar 

  • Kelly AJ (1984) Low charge density electrostatic atomization. IEEE-IA, IA-20: 267–273

  • Kozhenkov VN; Fuks NA (1976) Electrohydrodynamic atomisation of liquids. Russian Chem Rev 45: 1179–1184

    Google Scholar 

  • Lefebvre AH (1989) Atomization and sprays. New York: Hemisphere

    Google Scholar 

  • Lord Rayleigh FRS (1882) On the equilibrium of liquid conducting masses charged with electricity. London Philos Mag and J of Sci 14: 184–186

    Google Scholar 

  • Lüttgens U; Dülcks Th; Röllgen FW (1992) Field induced disintegration of glycerol solutions under vacuum and atmospheric pressure conditions studied by optical microscopy and mass spectrometry. Surface Sci 266: 197–203

    Google Scholar 

  • Meesters GMH; Vercoulen PHW; Marijnissen JCM; Scarlett B (1992) Generation of micron-sized droplets from the Taylor cone. J Aerosol Sci 23: 37–49

    Google Scholar 

  • Nadarajah S; Swift DL (1993) Generation of polydisperse aerosols of 0.5–10 μm diameter by electrospray. Conf. Proc. Amer. Assoc. Aerosol Rsrch., Oak Brook, IL, 269

  • O'Hern TJ; Rader DJ (1993) Practical application of In situ aerosol measurement. Halon Alternatives Tech. Working Conf., New Mexico, US DOE Report no. SAND-93-0449C

  • Pfeifer RJ; Hendricks CD (1967) Charge-to-mass relationships for electrohydrodynamically sprayed liquid droplets. Phys Fluids 10: 2149–2154

    Google Scholar 

  • Press WH; Flannery BP; Teukolsky SA; Vetterling WT (1989) Numerical recipes (FORTRAN Version). New York: Cambridge University Press

    Google Scholar 

  • Rosell-Llompart J; Fernández de la Mora J (1994) Generation of monodisperse droplets 0.3 to 4 μm in diameter from electrified cone-jets of highly conducting and viscous liquids. J Aerosol Sci 25: 1093–1119

    Google Scholar 

  • Shackleford JR (1985) Introduction to materials science for engineers. New York: Macmillan

    Google Scholar 

  • Smith DPH (1986) The electrohydrodynamic atomization of liquids. IEEE-IA, IA-22: 527–535

  • Snarski SR (1988) The interaction of electrohydrodynamically generated liquid droplets. Masters Thesis, University of Notre Dame, IN

    Google Scholar 

  • Snarski SR; Dunn PF (1991) Experiments characterizing the interaction between two spray of electrically charged liquid droplets. Exp Fluids 11: 268–278

    Google Scholar 

  • Soo SL (1989) Particulates and continuum-multiphase fluid dynamics. New York: Hemisphere

    Google Scholar 

  • Tang K; Gomez A (1994) On the structure of an electrostatic spray of monodisperse droplets. Phys Fluids 6: 2317–2332

    Google Scholar 

  • Taylor GI (1964) Disintegration of water drops in an electric field. Proc Roy Soc London, Series A 280: 383–397

    Google Scholar 

  • Taylor JR (1982) An introduction to uncertainty analysis. Mill Valley, CA: University Science Books, Oxford University Press

    Google Scholar 

  • True, MA (1980) Modelling of electrostatic spray plumes. Conf. Record, IEEE-IAS: 993–997

  • Vonnegut B; Neubauer RL (1952) Production of monodisperse liquid particles by electrical atomization. J Colloid Sci 7: 616–622

    Google Scholar 

  • Wang SH; Chang JS; Berezin AA (1993) Atomization characteristics of electrohydrodynamic limestone-water slurry spray. J Electrostatics 30: 235–246

    Google Scholar 

  • Zelany J (1914) The electrical discharge from liquid points and a hydrostatic method of measuring the electrical intensity at their surfaces. J Phys Rev 3: 69–91

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Particle Dynamics Laboratory, Hessert Center for Aerospace Research, Department of Aerospace & Mechanical Engineering, University of Notre Dame, 46556, Notre Dame, IN, USA

    J. M. Grace & P. F. Dunn

Authors
  1. J. M. Grace
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. P. F. Dunn
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Grace, J.M., Dunn, P.F. Droplet motion in an electrohydrodynamic fine spray. Experiments in Fluids 20, 153–164 (1996). https://doi.org/10.1007/BF00190271

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00190271

Keywords

Search

Navigation