Non-monotonic settling of a sphere in a cornstarch suspension

ORAL

Abstract

Cornstarch suspensions exhibit remarkable behavior. Here, we present two surprising observations for a sphere settling in such a suspension: In the bulk of the liquid the velocity of the sphere oscillates around a terminal value, without damping. Near the bottom the sphere comes to a full stop, but then accelerates again towards a second stop. This stop-go cycle is repeated several times before the object reaches the bottom. We show that common shear thickening or linear viscoelastic models cannot account for the observed phenomena, and propose a minimal jamming model to describe the behavior at the bottom.

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Authors

  • Devaraj van der Meer

    University of Twente, University of Twente, NL, University of Twente, The Netherlands

  • Stefan von Kann

    University of Twente, NL

  • Jacco H. Snoeijer

    University of Twente, NL, Physics of Fluids, University of Twente, The Netherlands, University of Twente, Physics of Fluids, University of Twente

  • Detlef Lohse

    Physics of Fluids Group, University of Twente, Physics of Fluids, University of Twente, The Netherlands, University of Twente, NL, University of Twente, Physics of Fluids, University of Twente, The University of Twente