Abstract
The linear stability of an annular capillary liquid (external or internal) coating, undergoing a uniform axial elongation, is analysed. An appropriate initial-value problem is formulated and solved for the evolution of small perturbations on the free surface of the coating, thereby enabling a thorough description of the amplification envelopes (of maximal growth) and the wavenumbers of the instantaneously dominant perturbations.
Similarly to other related capillary-stability problems, it is observed that the elongational motion has, through the continual stretching of perturbation waves, an inhibiting effect upon perturbation growth. The present results demonstrate that the latter is further suppressed in the practically relevant case of small (relative to the instantaneous radius of the cylindrical surface being coated) coating thickness. It is thus suggested that this phenomenon may be utilised to improve the quality of coating in certain industrial processes where the very production of the coated body involves a significant elongation.
Similar content being viewed by others
References
Batchelor, G. K., Stability of a large gas bubble rising through liquid.J. Fluid Mech. 184 (1987) 399–422.
Bogy, D. B., Drop formation in a circular liquid jet.Ann. Rev. Fluid Mech. 11 (1979) 207–228.
Frankel, I. and Weihs, D., Stability of a capillary jet with linearly increasing axial velocity (with applications to shaped charges).J. Fluid Mech. 155 (1985) 289–307.
Frenkel, A. L., Babchin, A. J., Levich, B. G., Shlang, T. and Sivashinski, G. I., Annular flows can keep unstable films from breakup: Nonlinear saturation of capillary instability.J. Colloid and Interface Sci. 115 (1987) 225–233.
Goren, S. L., The instability of an annular thread of fluid.J. Fluid Mech. 12 (1962) 309–319.
Keller, J. B., Rubinow, S. I. and Tu, Y. O., Spatial instability of a jet.Phys. Fluids 16 (1973) 2052–2055.
Longuet-Higgins, M. S., Bubbles, breaking waves and hyperbolic jets at a free surface.J. Fluid Mech. 127 (1983) 103–121.
Mikami, T., Cox, R. G. and Mason, S. G., Breakup of extending liquid threads.Intl. J. Multiphase Flow 2 (1975) 113–138.
Moore, D. W. and Griffith-Jones, R., The stability of an expanding circular vortex sheet.Mathematika 21 (1974) 128–133.
Murray, J. D.,Asymptotic Analysis. Springer (1974) 164 pp.
Petrie, C. J. S. and Denn, M. M., Instabilities in polymer processing.AIChE J. 22 (1976) 209–236.
Quéré, D., di Meglio, J. M. and Brochard-Wyart, F., Spreading of liquids on highly curved surfaces.Science 249 (1990) 1256–1260.
Sanz, A. and Messeguer, J., One-dimensional linear analysis of the compound jet.J. Fluid Mech. 159 (1985) 55–68.
Tomotika, S., Breaking up of a drop of viscous liquid immersed in another viscous fluid which is extending at a uniform rate.Proc. R. Soc. Lond. A153 (1936) 302–318.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Biber, E., Frankel, I. Elongational stabilization of capillary coating. Appl. Sci. Res. 52, 355–370 (1994). https://doi.org/10.1007/BF00936837
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00936837