Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-28T16:23:44.303Z Has data issue: false hasContentIssue false

Modelling film flows down a fibre influenced by nozzle geometry

Published online by Cambridge University Press:  28 August 2020

H. Ji*
Affiliation:
Department of Mathematics, University of California, Los Angeles, Los Angeles, CA90095, USA
A. Sadeghpour
Affiliation:
Mechanical and Aerospace Engineering Department, University of California, Los Angeles, Los Angeles, CA90095, USA
Y. S. Ju
Affiliation:
Mechanical and Aerospace Engineering Department, University of California, Los Angeles, Los Angeles, CA90095, USA
A. L. Bertozzi
Affiliation:
Department of Mathematics, University of California, Los Angeles, Los Angeles, CA90095, USA Mechanical and Aerospace Engineering Department, University of California, Los Angeles, Los Angeles, CA90095, USA
*
Email address for correspondence: [email protected]

Abstract

We study the effects of nozzle geometry on the dynamics of thin fluid films flowing down a vertical cylindrical fibre. Recent experiments show that varying the nozzle diameter can lead to different flow regimes and droplet characteristics in the film. Using a weighted residual modelling approach, we develop a system of coupled equations that account for inertia, surface tension effects, gravity and a film stabilization mechanism to describe both near-nozzle fluid structures and downstream bead dynamics. We report good agreement between the predicted droplet properties and the experimental data.

Type
JFM Rapids
Copyright
© The Author(s), 2020. Published by Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Chang, H.-C. & Demekhin, E. A. 1999 Mechanism for drop formation on a coated vertical fibre. J. Fluid Mech. 380, 233255.CrossRefGoogle Scholar
Craster, R. V. & Matar, O. K. 2006 On viscous beads flowing down a vertical fibre. J. Fluid Mech. 553, 85105.CrossRefGoogle Scholar
Craster, R. V. & Matar, O. K. 2009 Dynamics and stability of thin liquid films. Rev. Mod. Phys. 81 (3), 11311198.CrossRefGoogle Scholar
Duprat, C., Ruyer-Quil, C. & Giorgiutti-Dauphiné, F. 2009 Spatial evolution of a film flowing down a fiber. Phys. Fluids 21 (4), 042109.CrossRefGoogle Scholar
Frenkel, A. L. 1992 Nonlinear theory of strongly undulating thin films flowing down vertical cylinders. Europhys. Lett. 18 (7), 583588.CrossRefGoogle Scholar
de Gennes, P. G. 1985 Wetting: statics and dynamics. Rev. Mod. Phys. 57, 827863.CrossRefGoogle Scholar
Ji, H., Falcon, C., Sadeghpour, A., Zeng, Z., Ju, Y. S. & Bertozzi, A. L. 2019 Dynamics of thin liquid films on vertical cylindrical fibres. J. Fluid Mech. 865, 303327.CrossRefGoogle Scholar
Kalliadasis, S. & Chang, H.-C. 1994 Drop formation during coating of vertical fibres. J. Fluid Mech. 261, 135168.CrossRefGoogle Scholar
Kalliadasis, S., Ruyer-Quil, C., Scheid, B. & Velarde, M. G. 2011 Falling Liquid Films. Springer Science & Business Media, vol. 1.Google Scholar
Kliakhandler, I. L., Davis, S. H. & Bankoff, S. G. 2001 Viscous beads on vertical fibre. J. Fluid Mech. 429, 381390.CrossRefGoogle Scholar
Quéré, D. 1999 Fluid coating on a fiber. Annu. Rev. Fluid Mech. 31 (1), 347384.CrossRefGoogle Scholar
Reisfeld, B. & Bankoff, S. G. 1992 Non-isothermal flow of a liquid film on a horizontal cylinder. J. Fluid Mech. 236, 167196.CrossRefGoogle Scholar
Ruyer-Quil, C. & Kalliadasis, S. 2012 Wavy regimes of film flow down a fiber. Phys. Rev. E 85 (4), 046302.CrossRefGoogle ScholarPubMed
Ruyer-Quil, C., Treveleyan, P., Giorgiutti-Dauphiné, F., Duprat, C. & Kalliadasis, S. 2008 Modelling film flows down a fibre. J. Fluid Mech. 603, 431462.CrossRefGoogle Scholar
Ruyer-Quil, C., Trevelyan, S. P. M. J., Giorgiutti-Dauphiné, F., Duprat, C. & Kalliadasis, S. 2009 Film flows down a fiber: modeling and influence of streamwise viscous diffusion. Eur. Phys. J. Spe. Top. 166 (1), 8992.CrossRefGoogle Scholar
Sadeghpour, A., Zeng, Z., Ji, H., Dehdari Ebrahimi, N., Bertozzi, A. L. & Ju, Y. S. 2019 Water vapor capturing using an array of traveling liquid beads for desalination and water treatment. Sci. Adv. 5 (4), eaav7662.CrossRefGoogle ScholarPubMed
Sadeghpour, A., Zeng, Z. & Ju, Y. S. 2017 Effects of nozzle geometry on the fluid dynamics of thin liquid films flowing down vertical strings in the Rayleigh–Plateau regime. Langmuir 33, 62926299.CrossRefGoogle ScholarPubMed
Shkadov, V. Ya. 1967 Wave flow regimes of a thin layer of viscous fluid subject to gravity. Fluid Dyn. 2 (1), 2934.CrossRefGoogle Scholar
Trifonov, Yu. Ya. 1992 Steady-state traveling waves on the surface of a viscous liquid film falling down on vertical wires and tubes. AIChE J. 38 (6), 821834.CrossRefGoogle Scholar
Zeng, Z., Sadeghpour, A. & Ju, Y. S. 2019 A highly effective multi-string humidifier with a low gas stream pressure drop for desalination. Desalination 449, 92100.CrossRefGoogle Scholar