Ripples in Wetting Film formed by Moving Meniscusстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
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Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
Аннотация:We carry out a theoretical investigation of the evolution of a wetting film formed by pressing a bubble
against a solid substrate. Our model incorporates the effects of capillarity and Derjaguin-Landau-Verwey-
Overbeek (DLVO) (van der Waals and electrostatic) components of the disjoining pressure. Rapid changes in
the relative position of the bubble and the substrate are shown to result in surprisingly rich dynamics of wetting
film deformations. Even for stable films, we find transient rippled deformations with several points of local
maximum of wetting film thickness and discuss how their evolution depends on changes in the meniscus
position relative to the substrate and the disjoining pressure parameters. A connection is made to the recently
reported experimental observations of one such rippled deformation, the so-called wimple, characterized by a
local minimum of the thickness in the center, surrounded by a ring of greater film thickness and bounded at the
outer edge by the barrier rim. Guidelines are provided for experimental detection of more complex rippled
deformations in stable wetting films. Development of instability is studied in a situation when the electrostatic
component of disjoining pressure is destabilizing, with particular emphasis on the nonlinear evolution and
rupture of the film. Potential applications of our findings to small-scale mixing and deposition of nanoparticles
are discussed.