No abstract

In this work numerical solutions of the dip coating problem in the presence of a soluble surfactant are shown. Predictions of film thickening as well as thickening factors are in very good agreement with published experimental data, showing that pure hydrodynamic modeling suffices to mimic the process. Our numerical solutions provide a wealth of information on the functioning of the dip coating system; they show the appearance of a second stagnation point located in the bulk phase near the dynamic meniscus and they give clues about how the flow patterns might change as the surfactant becomes less soluble.

In this work a numerical analysis of two-dimensional Faraday waves is presented. This study is based on direct numerical simulation of Navier-Stokes and continuity equations with appropriate boundary conditions. Stability maps on the (F-␣) plane for viscous liquid layers with equilibrium depths between 5ϫ10 Ϫ5 m and 10 Ϫ5 m are presented; comparisons are made with the linear stability predictions obtained with Benjamin and Ursell's model for an inviscid fluid and with Kumar and Tuckerman's model for a viscous fluid. Regions in which time-periodic solutions are no longer obtained and nonlinear effects are relevant, and are also delimited and analyzed: in these zones the disintegration of the free surface into drops may take place.