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Hydrodynamics of the rupture of thin liquid films

Published online by Cambridge University Press:  26 April 2006

A. B. Pandit  and
J. F. Davidson
A. B. Pandit
Affiliation:
Department of Chemical Engineering, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, UK
J. F. Davidson
Affiliation:
Department of Chemical Engineering, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, UK
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Abstract

Experiments on the rupture of a thin spherical liquid film – formed from a solution of surfactant – are reported. The mean film thickness, prior to rupture, was measured by an electrical conductivity method: initial film thicknesses were of order 0.3–0.9 μm. For an unruptured film, drainage due to gravity reduced the film thickness; the films ruptured naturally at a thickness of order 0.05–0.09 μm.

When the spherical film was punctured by a needle, a hole was formed, which grew rapidly, bounded by a liquid rim. As the rim moved, it collected the liquid from the film; but the rim was itself unstable, generating droplets continuously. The rim velocity, of order 10 m/s, was measured by cine photography at 2000 frames/s. Measured rim velocities compared well with a simple theoretical result derived from either (i) a force balance on the rim or (ii) an energy balance, which demonstrates that there is continuous energy dissipation due to collision between the moving rim and the elements of the stationary film.

When the moving rim had swept up the whole spherical film, much of the rim had disintegrated into droplets, but the remaining rim finally converged to give an ‘implosion’ generating more droplets. These droplets, together with those generated by fragmentation of the rim in flight, were collected: their number, of order 104, was measured by an image analyser, which also measured mean droplet size, of order 102 μm. The total droplet area was a few per cent of the area of the original spherical film.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 212 , March 1990 , pp. 11 - 24
Copyright
© 1990 Cambridge University Press

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References

Blanchard, D. C.: 1963 Electrification of the atmosphere. In Progress in Oceanography, vol. 1 (ed. M. Sears), p. 71, Pergamon.
Culick, F. E. C.: 1960 Comments on a ruptured soap film. J. Appl. Phys. 31, 1128.Google Scholar
Dombrowski, N. & Fraser, R. P., 1954 A photographic investigation into the disintegration of liquid sheets. Phil. Trans. R. Soc. Lond. A 247, 101.Google Scholar
Majumdar, S. R. & Michael, D. H., 1976 The equilibrium and stability of two-dimensional pendent drops. Proc. R. Soc. Lond. A 351, 89.Google Scholar
Mysels, K. J. & Vijayendran, B. R., 1973 Film bursting V. The effect of various atmospheres and the anomaly of Newton black films. J. Phys. Chem. 77, 1692.Google Scholar
Pandit, A. B., Philip, J. & Davidson, J. F., 1987 The generation of small bubbles in liquids. In Intl. Chem. Reac. Engineering Conf., II, Pune, India, p. 72.Google Scholar
Patzer, J. F. & Homsy, G. M., 1975 Hydrodynamic stability of thin spherically concentric fluid shells. J. Colloid Interface Sci. 51, 499.Google Scholar
Ranz, W. E.: 1959 Some experiments on the dynamics of liquid films. J. Appl. Phys. 30, 1950.Google Scholar
Rayleigh, Lord: 1891 Some applications of photography. Nature 44, 249. (Also Scientific Papers vol. 3, 1898, p. 441.)Google Scholar
Rayleigh, Lord: 1945 Theory of Sound, vol II, p. 360. Dover.
Rutland, D. F. & Jameson, G. J., 1971 A non-linear effect in the capillary instability of liquid jets. J. Fluid Mech. 46, 267.Google Scholar
Sheludko, A.: 1967 Thin liquid films. In Advances in Colloid and Interface Science, vol. 1, p. 391. Elsevier.
Taylor, G. I.: 1960 Formation of thin fiat sheets of water. Proc. R. Soc. Lond. A, 259, 1. (Also Scientific Papers of G. I. Taylor, Vol. IV, 1971, p. 378.)Google Scholar
Taylor, G. I. & Michael, D. H., 1973 On making holes in a sheet of fluid. J. Fluid Mech. 58, 625.Google Scholar