title: Elastic convection in vibrated viscoplastic fluids.
abstract: We observe a new type of behavior in a shear-thinning yield stress fluid: freestanding convection rolls driven by vertical oscillation. The convection occurs without the constraint of container boundaries, yet the diameter of the rolls is spontaneously selected for a wide range of parameters. The transition to the convecting state occurs without hysteresis when the amplitude of the plate acceleration exceeds a critical value. We find that a nondimensional stress, the stress due to the inertia of the fluid normalized by the yield stress, governs the onset of the convective motion.
authors.affiliation: Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Hayato
authors.initials: H
authors.lastname: Shiba
authors.forename: Jori E
authors.initials: JE
authors.lastname: Ruppert-Felsot
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Murayama
authors.forename: Qi
authors.initials: Q
authors.lastname: Ouyang
authors.forename: Masaki
authors.initials: M
authors.lastname: Sano