Accueil > Séminaires > Précédents séminaires > Can liquids slide ? – Extracting the Hydrodynamic Boundary Condition from Surface Perturbations in Thin Liquid Films

Can liquids slide ? – Extracting the Hydrodynamic Boundary Condition from Surface Perturbations in Thin Liquid Films

Oliver Bäumchen Max Planck Institute for Dynamics and Self-Organization, Göttingen, Germany

For the motion of complex liquids on the micro- and nanoscale, the hydrodynamic boundary condition at the solid/liquid interface plays a fundamental role. In recent years much has been learned about this slip boundary condition from flows that are exclusively driven by capillary forces. In dewetting thin liquid films, exhibiting a three-phase contact line, the liquid is accumulated in a rim that features characteristic shapes. The evolution of the rim morphology in fact represents a unique fingerprint of hydrodynamic slippage [1,2]. For liquid films supported by cylindrical fibers, we show that the growth of surface perturbations, resulting from a Rayleigh-Plateau-type instability, allows for quantifying hydrodynamic slip [3]. Finally, it is demonstrated that also the opposite approach, i.e. the capillary levelling of an initially perturbed free surface of a thin liquid film [4], is sensitive to the slip boundary condition at the solid/liquid interface [5]. The adaptation of thin film models, based on Stokes flow, the lubrication approximation and comprising hydrodynamic slip, to the experimental data enables to access the slip length of polymeric liquids of various molecular properties.
In this presentation, I will review a series of interfacial phenomena and thin film flow scenarios that represent powerful tools for quantifying hydrodynamic slippage by matching experiments, numerical simulations and analytical theory.

[1] O. Bäumchen, R. Fetzer, and K. Jacobs, Phys. Rev. Lett. 103, 247801 (2009).
[2] O. Bäumchen, L. Marquant, R. Blossey, A. Münch, B. Wagner, and K. Jacobs, Phys. Rev. Lett. 113, 014501 (2014).
[3] S. Haefner, M. Benzaquen, O. Bäumchen, T. Salez, R. Peters, J.D. McGraw, K. Jacobs, E. Raphaël, and K. Dalnoki-Veress, Nature Communications 6, 7409 (2015).
[4] J.D. McGraw, T. Salez, O. Bäumchen, E. Raphaël, and K. Dalnoki-Veress, Phys. Rev. Lett. 109, 128303 (2012).
[5] M. Ilton et al., in preparation (2016).