Buoyant ellipsoidal particles at high Galileo numbers

ORAL

Abstract

Large and buoyant ellipsoidal particles display path instabilities at sufficiently high Galileo numbers due to the break-up of the wake symmetry. Using direct numerical simulations with the immersed boundary method, we analyse the dynamics of a freely rising buoyant particle by varying its aspect ratio over a range of Galileo numbers. The density ratio of the solid particle to the fluid phase is held constant. The study employs a single buoyant particle in an opposing counter flow. For a fixed particle Reynolds number, we set the flow conditions such that the net buoyancy force on the particle balances its drag. We link rising modes to the particles’ Galileo number and analyse the rise velocity for various particle shapes and aspect ratios.

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Presenters

  • Martin Assen

    University of Twente

Authors

  • Martin Assen

    University of Twente

  • Vamsi Spandan

    University of Twente, Harvard University

  • Richard Stevens

    University of Twente, Univ of Twente

  • Roberto Verzicco

    Univ of Roma, University of Rome, Università di Roma Tor Vergata, PoF University of Twente, Univ of Roma Tor Vergata, Univ. of Twente, University of Roma, Univ of Roma "Tor Vergata", University of Roma, University of Twente, Univ of Twente, Univ of Rome 'Tor Vergata'

  • Detlef Lohse

    University of Twente, Physics of Fluids and Max Planck Center for Complex Fluids Dynamics, University of Twente, Enschede, The Netherlands, Univ of Twente, Univ of Twente, Max Plank Institute for Dynamics and Self-Organization, Twente Tech Univ, University of Twente, Max Planck Center for complex fluid dynamics