Surface and Interfacial Tensions from the Profile of a Sessile Drop

Sessile drops and captive bubbles resting at a plane solid surface but separated from the surface by a thin film of the surrounding fluid, appear to possess angles of contact of 180°. The limiting height, Z∞180 of a very large sessile drop formed under these conditions is related to the interfacial...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Proceedings of the Royal Society of London. Series A, Mathematical and physical sciences Mathematical and physical sciences, 1972-09, Vol.329 (1579), p.421-431
Hauptverfasser: Padday, J. F., Pitt, A. R.
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Sessile drops and captive bubbles resting at a plane solid surface but separated from the surface by a thin film of the surrounding fluid, appear to possess angles of contact of 180°. The limiting height, Z∞180 of a very large sessile drop formed under these conditions is related to the interfacial tension, γ, by the expression γ = ¼∆pg (Z∞180)2, where ∆p is the density difference of the two fluids and g, the gravitational acceleration. As very large drops are not usually obtained experimentally the maximum height of a drop of intermediate size was measured and used in the equation with an appropriate correction factor. The correction factor was obtained from tables of the profiles of sessile drops. The correction factor is invariant for all values of γ, ∆p and g. The method is tested experimentally and shown to agree with the results obtained by other methods for a number of widely differing systems. The reproducibility and sources of error are discussed.
ISSN:1364-5021
0080-4630
1471-2946
2053-9169
DOI:10.1098/rspa.1972.0121