Wetting variational theory

Generally, the variation of the solid s density, which composes the wet particle, is less than a few percent. As a consequence, constant solid density may be assumed to simplify the model. Thus, by using the mixture theory, the density of the dispersed phase can be expressed as... 

Finally, we consider the hydrodynamic theory of thin liquid film rupture. The stability of the liquid films to a great extent is ensured by the property of the adsorbed surfactant to damp the thermally excited fluctuation capillary waves representing peristaltic variations in the film thickness [6]. In addition to the theory of stability of free foam and emulsion films, we consider also the drainage and stability of wetting films, which find application in various coating technologies [7]. 

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