title: Delayed capillary breakup of falling viscous jets.
abstract: Thin jets of viscous fluid like honey falling from capillary nozzles can attain lengths exceeding 10 m before breaking up into droplets via the Rayleigh-Plateau (surface tension) instability. Using a combination of laboratory experiments and WKB analysis of the growth of shape perturbations on a jet being stretched by gravity, we determine how the jet's intact length l(b) depends on the flow rate Q, the viscosity η, and the surface tension coefficient γ. In the asymptotic limit of a high-viscosity jet, l(b)∼(gQ(2)η(4)/γ(4))(1/3), where g is the gravitational acceleration. The agreement between theory and experiment is good, except for very long jets.
authors.affiliation: Institute for Advanced Studies in Basic Sciences, Zanjan 45195-1159, Iran and Laboratoire de Physique Statistique, École Normale Supérieure, 24 rue Lhomond, 75231 Paris Cedex 05, France.
authors.forename: A
authors.initials: A
authors.lastname: Javadi
authors.affiliation: School of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW, United Kingdom.
authors.forename: J
authors.initials: J
authors.lastname: Eggers
authors.affiliation: Laboratoire de Physique Statistique, École Normale Supérieure, 24 rue Lhomond, 75231 Paris Cedex 05, France and Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: Bonn
authors.affiliation: Institute for Advanced Studies in Basic Sciences, Zanjan 45195-1159, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Habibi
authors.affiliation: Lab FAST, UPMC, Université Paris-Sud, CNRS, Bâtiment 502, Campus Université, 91405 Orsay, France.
authors.forename: N M
authors.initials: NM
authors.lastname: Ribe