The transition region between a thin film and the capillary meniscus

✍ Scribed by Peter Atanassov Kralchevsky; Ivan Boyanov Ivanov

• Publisher: Elsevier Science
• Year: 1985
• Tongue: English
• Weight: 337 KB
• Volume: 121
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(85)87166-9

✦ Synopsis

Generalized Laplacc equations. nccounCng for the variations or the surracc knsion and the disjoining pressure in the transition region. are derived. They are used 10 obtain inlegral expressions for the line and Iransversal tensions. 1. Conditions for equilibrium of the transition region We consider a symmetrical planar thin liquid film in the absence of external fields, encircled by a capil-l&-y meniscus of the same liquid (fig. 1). Close to the axis of symmetry 02 the film has constant thickness h (defined as the distance between the two surfaces of tension each of them with film surface tension of>. Far from Oz (in the meniscus) the disjoining pressure 3 = 0, the surface tension of the meniscus is a constant, 2, and the generatix of the surface Z(X) satifies the Laplace equation [ 11. In the intermediate region the two surfaces interact and since the interaction energy depends on the distance between them, the surface tension in this region u(x) changes gradually from d to Op. The disjoining pressure IT is also a fimc-