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Pair statistics of oblate spheroids settling in a turbulent flow

Published online by Cambridge University Press:  30 April 2025

Prateek Anand Open the ORCID record for Prateek Anand [Opens in a new window]  and
Samriddhi Sankar Ray Open the ORCID record for Samriddhi Sankar Ray [Opens in a new window]
Prateek Anand*
Affiliation:
International Centre for Theoretical Sciences, Tata Institute of Fundamental Research, Bangalore 560089, India
Samriddhi Sankar Ray
Affiliation:
International Centre for Theoretical Sciences, Tata Institute of Fundamental Research, Bangalore 560089, India
*
Corresponding author: Prateek Anand, [email protected]
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Abstract

We perform direct numerical simulations of sub-Kolmogorov, inertial spheroids settling under gravity in homogeneous, isotropic turbulence, and find that small-scale clustering, measured via the correlation dimension, depends sensitively on the spheroid aspect ratio. In particular, such spheroids are shown to cluster more as their anisotropy increases. Further, the approach rate for pairs of spheroids is calculated and found to deviate significantly from the spherical-particle limit. Our study, spanning a range of Stokes numbers and aspect ratios, provides critical inputs for developing collision models to understand the dynamics of sedimenting, anisotropic particles in general, and ice crystals in clouds in particular.

JFM classification

Geophysical and Geological Flows: Atmospheric flows Mixing: Turbulent mixing
Type
JFM Papers
Information
Journal of Fluid Mechanics , Volume 1009 , 25 April 2025 , A69
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Copyright
© The Author(s), 2025. Published by Cambridge University Press

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