ABSTRACT
G. CALLEGARI, 1•2·* A. CALV01 and J. P. HULIN3 1Grupo de Medias Porosos, Facultad de lngenieria, Universidad de Buenos Aires, Paseo Colon 850, Capital Federal, /063, Argentina 2Textile Research Institute (TR/), 601 Prospect Avenue, Princeton, NJ 08536, USA 3 Laboratoire FAST, Bfitiment 502, Campus Paris-Sud, 91405 Orsay, France
Abstract-An experimental study of the constant velocity displacement of various water/glycerol solutions by air in poly(vinyl chloride) (PVC) capillary tubes is reported. This topic is of particular interest in relation to dewetting processes on surfaces covered by a liquid film. More specifically, variations of the dynamic contact angle with velocity and their relation to the physicochemical properties of the systems studied are investigated. These results and those of other authors are analyzed in the framework of both hydrodynamical and molecular approaches of the dynamic contact-angle problem. These comparisons indicate that either the molecular or the viscous dissipation mechanism may be dominant, depending on the system studied. These results are used to suggest explanations for apparent discrepancies between dewetting velocity measurements in different systems previously reported by the authors.
