Experimental characterization of thin films, droplets and rivulets using LED fluorescence

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Imaging based on fluorescence has been used in the past to investigate, mostly in a qualitative manner, liquid films occurring in various applications. In the present paper, a simple quantitative experimental setup and the associated calibration procedure are detailed for a configuration involving Rhodamin B or Rhodamin 101 excited with light-emitting diodes (LEDs). The measurement procedure has been first validated for an open-channel flow considering different Reynolds numbers around 550 and has then been applied to the characterization of thin films, isolated droplets and rivulets. Using this technique the film thickness, film velocity and contact angle have been evaluated accurately for a variety of flow conditions.

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  1. Adomeit P, Renz U (2000) Hydrodynamics of three-dimensional waves in laminar falling films. Int J Multiphase Flow 26(7):1183–1208

  2. Aguinaga S, Bouchet JP (2009) Quantitative assessment by UV fluorescence of rain water flow on vehicle body in Jules Verne Climatic Wind tunnel. In: 7th FKFS conference “Progress in vehicle aerodynamics and thermal management”, Stuttgart, Germany

  3. Alekseenko S, Nakoryakov V, Pokusaev B (1994) Wave flow of liquid films. Begell House, New York

  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(12):121704

  5. Ausner I (2006) Experimental investigations on multi-phase film flows. PhD thesis, Technical University Berlin

  6. Bordás R, Hagemeier T, Thévenin D, Wunderlich B (2006) LDV-Signale beinhalten mehr Informationen als nur die Geschwindigkeit. In: Lasermethoden in der Strömungsmesstechnik, GALA, pp. 23/1–23/7

  7. Brinkmann B, Möller T (2009) Dickenbestimmung eines schubspannungsgetriebenen Wandfilmes auf einer geneigten ebenen Platte mittels Laserlichtschnitt. In: 17. GALA-Fachtagung, Erlangen, Deutschland, ISBN 978-3-9805613-5-8

  8. Chinnov E, Kharlamov S, Saprykina A, Zhukovskaya O (2007) Measuring deformations of the heated liquid film by the fluorescence method. Thermophys Aeromech 14:241–246

  9. Culkin J, Davis S (1984) Meandering of water rivulets. AlChE J 30:263–267

  10. Dhiman R, Chandra S (2009) Rupture of thin films formed during droplet impact. Proc R Soc A 466:1229–1245

  11. Eckbreth A (1988) Laser diagnostics for combustion temperature and species. Gordon and Breach Publisher, NY

  12. Greszik D, Yang H, Dreier T, Schulz C (2011) Measurement of water film thickness by laser-induced fluorescence and Raman imaging. Appl Phys B 102:123–132

  13. Hagemeier T, Hartmann M, Thévenin D (2011) Practice of vehicle soiling investigationsa review. Int J Multiphase Flow 37(8):860–875

  14. Hidrovo C, Hart D (2001) Emission reabsorption laser induced fluorescence (ERLIF) film thickness measurement. Meas Sci Technol 12:467–477

  15. Inagaki H, Saito A, Murakami M, Konomi T (1995) Development of two-dimensional oil film thickness distribution measuring system. SAE Paper 952346:59–67

  16. Johnson M, Schluter R, Bankoff S (1997) Fluorescent imaging system for global measurement of liquid film thickness and dynamic contact angle in free surface flows. Rev Sci Instrum 11:4097–4102

  17. Johnson M, Schluter R, Miksis M, Bankoff S (1999) Experimental study of rivulet formation on an inclined plate by fluorescent imaging. J Fluid Mech 394:339–354

  18. Kohse-Höinghaus K, Jeffries J (2002) Applied combustion diagnostics. Taylor & Francis, UK

  19. Lehwald A, Thévenin D, Zähringer K (2010) Quantifying macro-mixing and micro-mixing in a static mixer using two-tracer laser-induced fluorescence. Exp Fluids 48:823–836

  20. Lel V, Al-Sibai F, Leefken A, Renz U (2005) Local thickness and wave velocity measurement of wavy films with chromatic confocal imaging method and a fluorescence intensity technique. Exp Fluids 39:856–864

  21. Liu J, Paul J, Gollub J (1993) Measurement of the primary instabilities of film flows. J Fluid Mech 250:69–101

  22. Martinuzzi R, Tropea C (1993) The flow around surface-mounted, prismatic obstacles placed in a fully developed channel flow. J Fluids Eng 115:85–92

  23. Moran K, Inumaru J, Kawaji M (2002) Instantaneous hydrodynamics of a laminar wavy liquid film. Int J Multiphase Flow 28(5):731–755

  24. Mouza A, Vlachos N, Paras S, Karabelas A (2000) Measurement of liquid film thickness using a laser light absorption method. Exp Fluids 28:355–359

  25. Nusselt W (1916) Die Oberflächenkondensation des Wasserdampfes. VDI-Zeitschrift 60:541

  26. Schubring D, Ashwood A, Shedd T, Hurlburt E (2010) Planar laser-induced fluorescence (PLIF) measurements of liquid film thickness in annular flow. Part I: methods and data. Int J Multiphase Flow 36(10):815–824

  27. Schubring D, Shedd T, Hurlburt E (2010) Planar laser-induced fluorescence (PLIF) measurements of liquid film thickness in annular flow. Part II: analysis and comparison to models. Int J Multiphase Flow 36(10):825–835

  28. Šikalo Š, Wilhelm HD, Roisman I, Jakirlić S, Tropea C (2005) Dynamic contact angle of spreading droplets: experiments and simulations. Phys Fluids 17:1–13

  29. Tropea C, Yarin A, Foss J (2007) Handbook of experimental fluid mechanics. Springer, Berlin

  30. Winkels K, Peters I, Evangelista F, Riepen M, Daerr A, Limat L, Snoeijer J (2011) Receding contact lines: from sliding drops to immersion lithography. Eur Phys J Special Topics 192:195–205

  31. Zhou D, Gambaryan-Roisman T, Stephan P (2009) Measurement of water falling film thickness to flat plate using confocal chromatic sensoring technique. Exp Therm Fluid Sci 33(2):273–283

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The support and helpful discussions with Róbert Bordás and Christoph Roloff are gratefully acknowledged. Furthermore, the authors would like to thank Nichia Corporation for material support with LEDs.

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Correspondence to Thomas Hagemeier.

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Hagemeier, T., Hartmann, M., Kühle, M. et al. Experimental characterization of thin films, droplets and rivulets using LED fluorescence. Exp Fluids 52, 361–374 (2012) doi:10.1007/s00348-011-1232-x

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  • Contact Angle
  • Inclination Angle
  • Streamwise Velocity
  • Static Contact Angle
  • Dynamic Contact Angle