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Updated: Jun 1, 2026

Film Control to Study Contributions of Waves to Droplet Impact Dynamics on Thin Flowing Liquid Films
Published on: August 18, 2018
Dynamics of a thin liquid film with surface rigidity and spontaneous curvature
Michael H Köpf1, Svetlana V Gurevich, Thomas Wulf
1Institute for Theoretical Physics, University of Münster, D-48149 Münster, Germany. m.koepf@uni-muenster.de
Abstract:
The effect of rigid surfaces on the dynamics of thin liquid films that are amenable to the lubrication approximation is considered. It is shown that the Helfrich energy of the layer gives rise to additional terms in the time-evolution equations of the liquid film. The dynamics is found to depend on the absolute value of the spontaneous curvature, irrespective of its sign. Due to the additional terms, the effective surface-tension can be negative and an instability at intermediate wavelengths is observed. Furthermore, the dependence of the shape of a droplet on the bending rigidity as well as on the spontaneous curvature is discussed.
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