Nucleation Radius and Growth of a Liquid Meniscus
We consider a horizontal solid plate P placed above the free surface of a liquid L separated by a layer of air of thickness e ( approximately 0.1 mm). With suitable P /L pairs this layer of air is metastable for thicknesses e below a certain limit e c ( approximately 1 mm). We have found a way of setting up bridges connecting the liquid surface with the plate in a controlled way (axisymmetric meniscus of horizontal radius R ). The meniscus grows if R is above a certain threshold R c (e ). If R < R c the meniscus shrinks to zero. Our method allows precise measurements of R c (e ): We were able to do this using silicone oils and two types of plates P (with different contact angles). Our results are in good agreement with classical calculations by G. I. Taylor and E. Michael (J. Fluid Mech. 58, 625 (1973)). Furthermore, When R > R c (e ), we find that R grows linearly with time t and that dR dt ~ e -0.7 1 - e e c 2 .
Debregeas
G
Section de recherche, Institut Curie, 11, rue Pierre et Marie Curie, Paris Cedex 05, 75231, France
Brochard-Wyart
F