Titelangaben
Pujara, Nimish ; Arguedas-Leiva, José-Agustín ; Lalescu, Cristian ; Bramas, Bérenger ; Wilczek, Michael:
Shape- and scale-dependent coupling between spheroids and velocity gradients in turbulence.
In: Journal of Fluid Mechanics.
Bd. 922
(2021)
.
- R6.
ISSN 0022-1120
DOI: https://doi.org/10.1017/jfm.2021.543
Abstract
Rotations of spheroidal particles immersed in turbulent flows reflect the combined effects of fluid strain and vorticity, as well as the time history of these quantities along the particle’s trajectory. Conversely, particle rotation statistics in turbulence provide a way to characterise the Lagrangian properties of velocity gradients. Particle rotations are also important for a range of environmental and industrial processes where particles of various shapes and sizes are immersed in a turbulent flow. In this study, we investigate the rotations of inertialess spheroidal particles that follow Lagrangian fluid trajectories. We perform direct numerical simulations (DNS) of homogeneous isotropic turbulence and investigate the dynamics of different particle shapes at different scales in turbulence using a filtering approach.We find that the mean-square particle angular velocity is nearly independent of particle shape across all scales from the Kolmogorov scale to the integral scale. The particle shape does determine the relative split between different modes of rotation (spinning vs tumbling), but this split is also almost independent of the filter scale suggesting a Lagrangian scale-invariance in velocity gradients. We show how the split between spinning and tumbling can be quantitatively related to the particle’s alignment with respect to the fluid vorticity.
Weitere Angaben
Publikationsform: | Artikel in einer Zeitschrift |
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Begutachteter Beitrag: | Ja |
Institutionen der Universität: | Fakultäten > Fakultät für Mathematik, Physik und Informatik > Physikalisches Institut > Lehrstuhl Theoretische Physik I > Lehrstuhl für Theoretische Physik I - Univ.-Prof. Dr. Michael Wilczek Profilfelder > Advanced Fields > Nichtlineare Dynamik Fakultäten Fakultäten > Fakultät für Mathematik, Physik und Informatik Fakultäten > Fakultät für Mathematik, Physik und Informatik > Physikalisches Institut Fakultäten > Fakultät für Mathematik, Physik und Informatik > Physikalisches Institut > Lehrstuhl Theoretische Physik I Profilfelder Profilfelder > Advanced Fields |
Titel an der UBT entstanden: | Nein |
Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik > 530 Physik |
Eingestellt am: | 24 Feb 2022 11:23 |
Letzte Änderung: | 05 Jul 2022 09:40 |
URI: | https://eref.uni-bayreuth.de/id/eprint/67621 |