Two broad classes of models have been used to describe the motion of a contact line when the contact angle 0 deviates from the equilibrium value & : a) an Eyring approach, emphasizing the microscopic jump of a single molecule at the tip. b) a hydrodynamic approach, concentrating on the viscous losse
Dynamics of Wetting
โ Scribed by Rachid Chebbi
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 131 KB
- Volume
- 229
- Category
- Article
- ISSN
- 0021-9797
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โฆ Synopsis
We consider the dynamics of spreading of a small drop over a smooth solid surface. The analysis is concerned with complete wetting and accounts for capillary, viscous, and van der Waals effects, with two spreading geometries considered: cylindrical and axisymmetric. A complete description of the drop thickness, slope, and curvature profiles is provided. The model is not based on any fitting parameter, and the spreading laws are found to be in good agreement with published data obtained by different experimental techniques. The study evaluates the relative magnitudes of capillary, viscous, and disjoining-pressure effects and discusses the asymptotic form of the film profile and the existence of a singularity at the three-phase contact line. The model allows determination of the complete distribution of viscous dissipation in the whole drop, and the rate of viscous dissipation is related to the losses of the liquid drop free energy. Copyright 2000 Academic Press.
๐ SIMILAR VOLUMES
The spreading of a tiny macroscopic drop of a nonvolatile, completely wetting liquid over a flat solid is considered, assuming no gravitation. A liquid, in creeping, is subjected to capillary forces and van der Waals forces. This nonstationary and nonlinear problem in the dynamics of the wetting fil