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Detachment of droplets from cylinders in flow using an experimental analogue

Published online by Cambridge University Press:  20 April 2015

C. J. Hotz
Affiliation:
Institute for Mechanical Process Engineering and Mechanics, Karlsruhe Institut fuer Technologie, D-76131, Karlsruhe, Germany Fluid Dynamics Research Group, Curtin University, GPO Box U1987, Perth WA 6845, Australia
R. Mead-Hunter*
Affiliation:
Fluid Dynamics Research Group, Curtin University, GPO Box U1987, Perth WA 6845, Australia Health, Safety and Environment, School of Public Health, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth WA 6845, Australia
T. Becker
Affiliation:
Nanochemistry Research Institute, Curtin University, GPO Box U1987, Perth WA 6845, Australia
A. J. C. King
Affiliation:
Fluid Dynamics Research Group, Curtin University, GPO Box U1987, Perth WA 6845, Australia
S. Wurster
Affiliation:
Institute for Mechanical Process Engineering and Mechanics, Karlsruhe Institut fuer Technologie, D-76131, Karlsruhe, Germany
G. Kasper
Affiliation:
Institute for Mechanical Process Engineering and Mechanics, Karlsruhe Institut fuer Technologie, D-76131, Karlsruhe, Germany
B. J. Mullins
Affiliation:
Fluid Dynamics Research Group, Curtin University, GPO Box U1987, Perth WA 6845, Australia Health, Safety and Environment, School of Public Health, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth WA 6845, Australia
*
Email address for correspondence: r.mead-hunter@curtin.edu.au

Abstract

This work experimentally examines the detachment of liquid droplets from both oleophilic and oleophobic fibres, using an atomic force microscope. The droplet detachment force was found to increase with increasing fibre diameter and forces were higher for philic fibres than phobic fibres. We also considered the detachment of droplets situated on the intersection of two fibres and arrays of fibres (such as found in fibrous mats or filters) and found that the required detachment forces were higher than for similarly sized droplets on a single fibre, though not as high as expected based on theory. A model was developed to predict the detachment force, from single fibres, which agreed well with experimental results. It was found that the entire dataset (single and multiple fibres) could be best described by power law relationships.

Type
Papers
Copyright
© 2015 Cambridge University Press 

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References

Andrieu, C., Beysens, D. A., Nikolayev, V. S. & Pomeau, Y. 2002 Coalescence of sessile drops. J. Fluid Mech. 453, 427438.CrossRefGoogle Scholar
Aussillous, P. & Quere, D. 2004 Shapes of rolling liquid drops. J. Fluid Mech. 512, 133151.CrossRefGoogle Scholar
Bach, G. A., Koch, D. L. & Gopinath, A. 2004 Coalescence and bouncing of small aerosol droplets. J. Fluid Mech. 518, 157185.Google Scholar
Bayer, I. S. & Megaridis, C. 2006 Contact angle dynamics in droplets impacting on flat surfaces with different wetting characteristics. J. Fluid Mech. 558, 415449.CrossRefGoogle Scholar
Carroll, B. J. 1976 The accurate measurement of contact angle, phase contact areas, drop volume, and Laplace excess pressure in drop-on-fiber systems. J. Colloid Interface Sci. 57 (3), 488495.Google Scholar
Carroll, B. J. 1984 The equilibrium of liquid drops on smooth and rough circular cylinders. J. Colloid Interface Sci. 97 (1), 195200.CrossRefGoogle Scholar
Carroll, B. J. 1986 Equilibrium conformations of liquid drops on thin cylinders under forces of capillarity. A theory for the roll-up process. Langmuir 2, 248250.CrossRefGoogle Scholar
Dawar, S. & Chase, G. G. 2008 Drag correlation for axial motion of drops on fibers. Sep. Purif. Technol. 66, 613.Google Scholar
Dawar, S., Li, H., Dobson, J. & Chase, G. G. 2006 Drag correlation of drop motion on fibers. Drying Technol. 24, 12831288.CrossRefGoogle Scholar
Farhangi, M. M., Graham, P. J., Choudhury, N. R. & Dolatabadi, A. 2012 Induced detachment of coalescing droplets on superhydrophobic surfaces. Langmuir 28, 12901303.Google Scholar
Gac, J. M. & Gradon, L. 2012 Modeling of axial motion of small dropets deposited on smooth and rough fiber surfaces. Colloids Surf. A 414, 259266.Google Scholar
Gauthier, T., Hellstern, E., Kevrekidis, I. G. & Benzinger, J. 2012 Drop detachment and motion on fuel cell electrode materials. ACS Appl. Mater. Interfaces 4, 761771.CrossRefGoogle ScholarPubMed
Gilet, T., Terwagne, N. & Vandewalle, N. 2009 Digital microfluidics on a wire. Appl. Phys. Lett. 95, 014106.CrossRefGoogle Scholar
Gilet, T., Terwagne, N. & Vandewalle, N. 2010 Droplets sliding on fibres. Eur. Phys. J. E 31, 253262.CrossRefGoogle ScholarPubMed
Hao, P., Lu, C. & Yao, Z. 2013 Droplet detachment by air flow for microstructured superhydrophobic surfaces. Langmuir 29, 51605166.CrossRefGoogle ScholarPubMed
Leal, A. A., Deitzel, J. M., McKnight, S. H. & Gillespie, J. W. Jr. 2009 Interfacial behavior of high performance organic fibers. Polymer 50, 12281235.Google Scholar
Lorenceau, E. & Quere, D. 2004 Drops on a conical wire. J. Fluid Mech. 510, 2945.Google Scholar
McHale, G., Kab, N. A., Newton, M. I. & Rowan, S. M. 1997 Wetting of a high-energy fiber surface. J. Colloid Interface Sci. 186 (2), 453461.Google Scholar
McHale, G. & Newton, M. I. 2002 Global geometry and the equilibrium shapes of liquid drops on fibers. Colloids Surf. A 206 (1–3), 7986.Google Scholar
Mead-Hunter, R., Bergen, T., Becker, T., O’Leary, R. A., Kasper, G. & Mullins, B. J. 2012a Sliding/rolling phobic droplets along a fiber: measurement of interfacial forces. Langmuir 28, 34833488.Google Scholar
Mead-Hunter, R., King, A. J. C. & Mullins, B. J. 2012b Plateau-Rayleigh instability simulation. Langmuir 28, 67316735.Google Scholar
Mead-Hunter, R., Mullins, B. J., Becker, T. & Braddock, R. D. 2011 Evaluation of the force required to move a coalesced liquid droplet along a fiber. Langmuir 27 (1), 227232.Google Scholar
Mullins, B. J., Braddock, R. D., Agranovski, I. E. & Cropp, R. A. 2006 Observation and modelling of barrel droplets on vertical fibres subjected to gravitational and drag forces. J. Colloid Interface Sci. 300 (2), 704712.Google Scholar
Mullins, B. J., Braddock, R. D., Agranovski, I. E., Cropp, R. A. & O’Leary, R. A. 2005 Observation and modelling of clamshell droplets on vertical fibres subjected to gravitational and drag forces. J. Colloid Interface Sci. 284 (1), 245254.Google Scholar
Mullins, B. J., Pfrang, A., Braddock, R. D., Schimmel, T. & Kasper, G. 2007 Detachment of liquid droplets from fibres-experimental and theoretical evaluation of detchment force due to interfacial tension effects. J.  Colloid Interface Sci. 312, 333340.Google Scholar
Quere, D., Di Meglio, J.-M. & Brochard-Wyart, F. 1988 Wetting of fibers: theory and experiments. Rev. Phys. Appl. 23, 10231030.Google Scholar
de Ruiter, M., de Ruiter, J., Eral, H. B., Semprebon, C., Brinkman, M. & Mugele, F. 2012 Buoyant droplets on functional fibers. Langmuir 28, 1330013306.Google Scholar
Sader, J., Chon, J. & Mulvaney, P. 1999 Calibration of rectangular atomic force microscopy cantilevers. Rev. Sci. Instrum. 70, 39673969.Google Scholar
Sahu, R. P., Sinna-Ray, S., Yarin, A. L. & Pourdeyhimi, B. 2013 Blowing drops off a filament. Soft Matt. 9, 60536071.Google Scholar
Savva, N. & Kalliadasis, S. 2013 Droplet motion on inclined heterogeneous substrates. J. Fluid Mech. 725, 462491.CrossRefGoogle Scholar