Experiments in Fluids

, Volume 53, Issue 4, pp 1045–1056 | Cite as

Experimental investigation into three-dimensional wavy liquid films under the influence of electrostatic forces

  • Wilko Rohlfs
  • Georg F. Dietze
  • Herman D. Haustein
  • Oleg Yu. Tsvelodub
  • Reinhold Kneer
Research Article


Three-dimensional interfacial waves that develop on the free surface of falling liquid films are known to intensify heat and mass transfer. In this context, the present paper studies the effect of electrostatic forces applied to a falling film of dielectric liquid on its three-dimensional nonlinear wave dynamics. Therefore, measurements of the local film thickness using a confocal chromatic imaging method were taken, and the complex wave topology was characterized through photography. The experiments show a complex interaction between the electric field and the hydrodynamics of the falling film, whereby electrostatic forces were found to both increase and decrease wave peak height in different regions of the wave. Additionally, an electrically induced breakup of the three-dimensional wave fronts, which leads to a locally doubled frequency in streamwise direction, is found. The ability to influence the wave topology demonstrated here opens the possibility to optimize heat transfer processes in falling liquid films.


Particle Image Velocimetry Wave Front Liquid Film Spanwise Direction Wave Crest 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of symbols


Electrically induced surface force




Coordinate normal to free surface


Volumetric flow rate per unit width


Coordinate tangential to free surface




Phase velocity

x, y, z

Streamwise, crosswise and spanwise coordinates


CCI measuring distance to the fluid/wall


Electric displacement


Electric field strength


Capacitor plate distance




Thickness of the glass plate


Film thickness

Electric permittivity


Optical wavelength


Kinematic viscosity


Electric potential




Surface tension


Wavelength of surface waves


Reynolds number of the liquid film



The authors thank Anne Mettner and Norman Lahann for their contribution to the development of the three-dimensional excitation mechanism employed to obtain the experimental results. Additionally, we would like to thank the reviewers for their constructive comments and ideas on this manuscript, in particular with respect to Fig. 6. This work was financially supported by the Deutsche Forschungsgemeinschaft (grant number DFG KN 764/3-1).


  1. Adomeit P, Renz U (2000) Hydrodynamics of three-dimensional waves in laminar falling films. Int J Multiph Flow 26:1183–1208zbMATHCrossRefGoogle Scholar
  2. Alekseenko S, Cherdantsev A, Cherdantsev M, Isaenkov S, Kharlamov S, Markovich D (2011) Application of a high-speed laser-induced fluorescence technique for studying the three-dimensional structure of annular gas-liquid flow. Exp Fluids 1–13Google Scholar
  3. Alekseenko SV, Nakoryakov VE, Pokusaev BG (1994) Wave flow of liquid films. Begell House, ReddingGoogle Scholar
  4. Alekseenko SV, Antipin VA, Guzanov VV, Kharlamov SM, Markovich DM (2005) Three-dimensional solitary waves on falling liquid film at low reynolds numbers. Phys Fluids 17:1–4CrossRefGoogle Scholar
  5. Allen PHG, Karayiannis TG (1995) Electrohydrodynamic enhancement of heat transfer and fluid flow. Heat Recovery Syst CHP 15(5):389–423CrossRefGoogle Scholar
  6. Chang HC, Cheng M, Demekhin EA, Kopelevic DI (1994) Secondary and tertiary excitation of three-dimensional patterns of a falling film. J Fluid Dyn 270:251–275zbMATHGoogle Scholar
  7. Cohen-Sabban Joseph, Gaillard-Groleas Jerome, Pierre-Jean Crepin (2001) Quasi-confocal extended field surface sensing. Opt Metrol Roadmap Semicond Opt Data Storage Ind II 4449(1):178–183Google Scholar
  8. Darabi J, Ohadi MM, Desiatoun SV (2000) Falling film and spray evaporation enhancement using an applied electric field. J Heat Transf 122:741–748CrossRefGoogle Scholar
  9. Di Marco P, Grassi W (1994) Gas-liquid interface stability in presence of an imposed electric field. In: Proceedings of 12th UIT national conference, L’Aquila (I), pp 299–310Google Scholar
  10. Dietze GF (2010) Flow separation in falling liquid films. PhD thesis, RWTH AachenGoogle Scholar
  11. Dietze GF, Kneer R (2011) Flow separation in falling liquid films. Frontiers Heat Mass Transf 2Google Scholar
  12. Dietze GF, Leefken A, Kneer R (2008) Investigation of the backflow phenomenon in falling liquid films. JJ Fluid Mech 595:435–459zbMATHCrossRefGoogle Scholar
  13. Dietze GF, Al-Sibai F, Kneer R (2009) Experimental study of flow separation in laminar falling liquid films. J Fluid Mech 637:73–104zbMATHCrossRefGoogle Scholar
  14. Eames IW, Sabir HM (1997) Potential benefits of electrohydrodynamic enhancement of two-phase heat transfer in the design of refrigeration systems. Appl Therm Eng 17(1):79–92CrossRefGoogle Scholar
  15. Griffing EM, Bankoff SG, Miksis MJ, Schluter RA (2006) Electrohydrodynamics of thin flowing films. J Fluids Eng 128(2):276–283CrossRefGoogle Scholar
  16. Griffiths DJ (2006) Introduction to electrodynamics, 3rd edn. Pearson Education, DelhiGoogle Scholar
  17. Landau LD, Lifshitz EM (1975) Electrodynamics of continuous media, 2nd edn. Pergamon, OxfordGoogle Scholar
  18. Laohalertdecha S, Naphon P, Wongwises S (2007) A review of electrohydrodynamic enhancement of heat transfer. Renew Sustain Energy Rev 11(5):858–876CrossRefGoogle Scholar
  19. Lel VV, Al-Sibai F, Kneer R (2005) Local thickness and wave velocity measurement of wavy falling liquid films with chromatic confocal imaging method and a fluorescence intensity technique. Exp Fluids 39:856–864CrossRefGoogle Scholar
  20. Liu J, Schneider JB, Gollub JP (1994) Three-dimensional instabilities of film flows. Phys Fluids 7:55–67MathSciNetCrossRefGoogle Scholar
  21. Nosoko P, Yoshimura PN, Nagata T, Oyakawa K (1996) Characteristics of two-dimensional waves on a falling liquid film. Chem Eng Sci 51(5):725–732CrossRefGoogle Scholar
  22. Park CD, Nosoko T (2003) Three-dimensional wave dynamics on a falling film and associated mass transfer. AIChE J 49(11):2715–2727CrossRefGoogle Scholar
  23. Scheid B, Ruyer-Quil C, Manneville P (2006) Wave patterns in film flows: modelling and three-dimensional waves. J Fluid Mech 562:183–222MathSciNetzbMATHCrossRefGoogle Scholar
  24. Tailby SR, Portalski S (1962) The determination of the wavelength on a vertical film of liquid flowing down a hydrodynamically smooth plate. Chem Eng Res Des 40:114–122Google Scholar
  25. Tomar G, Gerlach D, Biswas G, Alleborn N, Sharma A, Durst F, Welch SWJ, Delgado A (2007) Two-phase electrohydrodynamic simulations using a volume-of-fluid approach. J Comput Phys 227:1267–1285MathSciNetzbMATHCrossRefGoogle Scholar
  26. Tsvelodub O, Samatov S (2010) Effect of the electric field on the wave flow regimes of a thin film of a viscous dielectric fluid. J Appl Mech Tech Phys 51:359–368MathSciNetCrossRefGoogle Scholar
  27. Whitham GB (1974) Linear and nonlinear waves. Wiley, New YorkzbMATHGoogle Scholar
  28. Yamashita K, Yabe A (1997) Electrohydrodynamic enhancement of falling film evaporation heat transfer and its long-term effect on heat exchangers. J Heat Transf 119:339–347CrossRefGoogle Scholar
  29. Zhou DW, Gambaryan-Roisman T, Stephan P (2009) Flow visualization and local measurement of forced convection heat transfer in a microtube. J Heat Transf 33(2):273–283Google Scholar

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Wilko Rohlfs
    • 1
  • Georg F. Dietze
    • 1
  • Herman D. Haustein
    • 1
  • Oleg Yu. Tsvelodub
    • 2
  • Reinhold Kneer
    • 1
  1. 1.Institute of Heat and Mass TransferRWTH Aachen UniversityAachenGermany
  2. 2.Institute of ThermophysicsSBRASNovosibirskRussia

Personalised recommendations