Modeling and simulation of viscoelastic film retraction

When inertia is relevant, as far as the opening hole does not interact with the wall bounding the film, the influence of liquid elasticity is very moderate, and the retraction dynamics tends to the one of Newtonian sheets; when the hole starts to interact with the solid wall, hole radius/opening velocity oscillations are detected. Such oscillations are enhanced at increasing elasticity. From the morphological point of view, the formation of a rim at the edge of the retracting film is observed. If inertial forces become less relevant with respect to viscous forces, R-oscillations disappear, the hole opening velocity goes through a maximum and then monotonically decays to zero, and no rim forms during the film retraction. Geometrical changes have the effect of enlarging or reducing the portion of the retraction dynamics not influenced by the presence of the solid wall with respect to the one governed by the hole-wall interactions.