Liquid film dynamics in horizontal and tilted tubes: dry spots and sliding drops

King, Andrew A.; Cummings, Linda J.; Naire, Shailesh; Jensen, Oliver E.

Abstract

Using a model derived from lubrication theory, we consider the evolution of a thin viscous film coating the interior or exterior of a cylindrical tube. The flow is driven by surface tension and gravity and the liquid is assumed to wet the cylinder perfectly. When the tube is horizontal, we use large-time simulations to describe the bifurcation structure of the capillary equilibria appearing at low Bond number. We identify a new film configuration in which an isolated dry patch appears at the top of the tube and demonstrate hysteresis in the transition between rivulets and annular collars as the tube length is varied. For a tube tilted to the vertical, we show how a long initially uniform rivulet can break up first into isolated drops and then annular collars, which subsequently merge. We also show that the speed at which a localized drop moves down the base of a tilted tube is non-monotonic in tilt angle.

Citation

King, A. A., Cummings, L. J., Naire, S., & Jensen, O. E. (2007). Liquid film dynamics in horizontal and tilted tubes: dry spots and sliding drops. Physics of Fluids, 19(4), Article 042102. https://doi.org/10.1063/1.2714569

• Journal Article Type: Article
• Acceptance Date: Feb 7, 2007
• Online Publication Date: Apr 11, 2007
• Publication Date: 2007-04
• Deposit Date: Feb 14, 2007
• Publicly Available Date: Oct 9, 2007
• Journal: Physics of Fluids
• Print ISSN: 1070-6631
• Electronic ISSN: 1089-7666
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 19
• Issue: 4
• Article Number: 042102
• DOI: https://doi.org/10.1063/1.2714569
• Public URL: https://nottingham-repository.worktribe.com/output/1017553
• Publisher URL: https://aip.scitation.org/doi/full/10.1063/1.2714569