Hindered and enhanced coalescence of drops in Stokes flows

We analyze axisymmetric near-contact motion of two drops under the action of an external force or imposed flow. It is shown that hydrodynamic stresses in the near-contact region that are associated with the outer (drop-scale) flow can qualitatively affect the drainage of the thin fluid film separati...

Full description

Saved in:
Bibliographic Details
Published in:Physical review letters 2004-03, Vol.92 (11), p.114501.1-114501.4, Article 114501
Main Authors: NEMER, M. B, CHEN, X, PAPADOPOULOS, D. H, BŁAWZDZIEWICZ, J, LOEWENBERG, M
Format: Article
Language:English
Subjects:
Drops and bubbles
Exact sciences and technology
Fluid dynamics
Fundamental areas of phenomenology (including applications)
Laminar flows
Low-reynolds-number (creeping) flows
Nonhomogeneous flows
Physics
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We analyze axisymmetric near-contact motion of two drops under the action of an external force or imposed flow. It is shown that hydrodynamic stresses in the near-contact region that are associated with the outer (drop-scale) flow can qualitatively affect the drainage of the thin fluid film separating the drops. If this far-field stress acts radially inward, film drainage is arrested at long times; exponential film drainage occurs if this stress acts outward. An asymptotic analysis of the stationary long-time film profile is presented for small-deformation conditions, and the critical strength of van der Waals attraction for film rupture is calculated. The effect of an insoluble surfactant is also considered. Hindered and enhanced drop coalescence are not predicted by the current theories, because the influence of the outer flow on film drainage is ignored.
ISSN:0031-9007
1079-7114
DOI:10.1103/PhysRevLett.92.114501