title: Capillary droplet propulsion on a fibre.
abstract: A viscous liquid film coating a fibre becomes unstable and decays into droplets due to the Rayleigh-Plateau instability (RPI). Here, we report on the generation of uniform droplets on a hydrophobized fibre by taking advantage of this effect. In the late stages of liquid column breakup, a three-phase contact line can be formed at one side of the droplet by spontaneous rupture of the thinning film. The resulting capillary imbalance leads to droplet propulsion along the fibre. We study the dynamics and the dewetting speed of the droplet as a function of molecular weight as well as temperature and compare to a force balance model based on purely viscous dissipation.
authors.affiliation: Saarland University, Department of Experimental Physics, 66041 Saarbrücken, Germany. k.jacobs@physik.uni-saarland.de.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Haefner
authors.forename: Oliver
authors.initials: O
authors.lastname: Bäumchen
authors.forename: Karin
authors.initials: K
authors.lastname: Jacobs
mesh_terms: D002197:Capillary Action; D005898:Glass / Q000737:chemistry*; D014783:Viscosity
chemical_list: C009753:fiberglass