Regensburg 2007 – scientific programme

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DY: Fachverband Dynamik und Statistische Physik

DY 14: Fluid dynamics II

DY 14.3: Talk

Tuesday, March 27, 2007, 11:45–12:00, H2

Response thin liquid films with splitted tongues? — •Bernhard Heislbetz — DLR Lampoldshausen, Institut für Raumfahrtantriebe, D-74239 Hardthausen

The stability of free fluid films in the presence of a harmonic modulated pressure or gravity field is investigated analytically. A linear stability analysis for the infinitesimal disturbances of the hydrodynamic problem for inviscid and also viscous fluids shows, that the dynamic of the interfaces of fluid films can be described by two coupled differential equations of the Mathieu-type. In the range of very thin film thicknesses we can show, that the time evolution of the film shapes is governed by an membrane-like equation coupled with an linear KdV-equation. By means of multiple time scale analysis we exemplify if and why thin liquid films response with splitted tongues.