Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-29T12:49:42.688Z Has data issue: false hasContentIssue false

A moving fluid interface. Part 2. The removal of the force singularity by a slip flow

Published online by Cambridge University Press:  11 April 2006

L. M. Hocking
Affiliation:
Department of Mathematics, University College London

Abstract

If the no-slip condition is used to determine the flow produced when a fluid interface moves along a solid boundary, a non-integrable stress is obtained. In part 1 of this study (Hocking 1976), it was argued that, when allowance was made for the presence of irregularities on the solid boundary, an effective slip coefficient could be found, which might remove the difficulty.

This paper examines the effect of a slip coefficient on the flow in the neighbourhood of the contact line. Particular cases which are solved in detail are liquid–gas interfaces at an arbitrary angle, and normal contact of fluids of arbitrary viscosity. The contribution of the vicinity of the contact line to the force on the boundary is obtained.

The inner region, near the contact line, must be matched with an outer flow, in which the no-slip condition can be applied, in order to obtain the total value of the force on the boundary. This force is determined for the flow of two fluids between parallel plates and in a pipe, with a plane interface. The enhanced resistance produced by the presence of the interface is calculated, and it is shown to be equivalent to an increase in the length of the column of fluid by a small multiple of the pipe radius.

Type
Research Article
Copyright
© 1977 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

Abramowitz, M. & Stegun, I. A. 1965 Handbook of Mathematical Functions. Dover.
Bataille, J. 1966 C. R. Acad. Sci. Paris, 262, 843.
Bhattacharji, S. & Savic, P. 1965 Proc. Heat Transfer Fluid Mech. Inst., p. 248.
Dussan V. E. B. & Davis, S. H. 1974 J. Fluid Mech. 65, 71.
Hocking, L. M. 1976 J. Fluid Mech. 76, 801.
Huh, C. & Scriven, L. E. 1971 J. Colloid Interface Sci. 35, 85.
Wagner, M. H. 1975 J. Fluid Mech. 72, 257.