Turbulent sedimentation: a new form of Rayleigh-Taylor mixing

ORAL

Abstract

The sedimentation of finite-size inertial particles in a Rayleigh-Taylor-like setup is studied by state-of-the-art direct numerical simulations.

The falling particles are observed to produce two distinct regions: a leading mixing layer with a linear concentration profile followed by a bulk region of uniform density.

Unlike classical RT turbulence, the mixing layer extension accelerates with an anomalous, non-integer exponent, while the bulk region moves at a constant velocity.

A one-dimensional model based on a local hindered settling law accurately captures the observed dynamics and its dependence on the density ratio.

*Japan Society for the Promotion of Science is acknowledged (grants 24K17210 and 24K00810). The authors acknowledge the computer time provided by the Scientific Computing & Data Analysis section of the Core Facilities at OIST and by HPCI, under the Research Project grant hp250021.

Publication: Simone Tandurella, Marco Edoardo Rosti, Stefano Musacchio, Guido Boffetta, "Turbulent sedimentation: a new form of Rayleigh-Taylor mixing", Phys. Rev. Lett. (submitted)

Presenters

  • Guido Boffetta

    • University of Torino

Authors

  • Guido Boffetta

    • University of Torino
  • Stefano Musacchio

    • Department of Physics, University of Torino
  • Marco Edoardo Rosti

    • Okinawa Institute of Science & Technology
    • Okinawa Institute of Science and Technology
  • Simone Tandurella

    • Okinawa Institute of Science and Technology Graduate University