Titre :

Tumbling rate of anisotropic particles in turbulent convection

Auteur(s) :

Jiang, Linfeng [Auteur]
Tsinghua University [Beijing] [THU]
Sun, Chao [Auteur]
University of Twente
Tsinghua University [Beijing] [THU]
Calzavarini, Enrico [Auteur]
Unité de Mécanique de Lille - ULR 7512 [UML]

Titre de la manifestation scientifique :

72nd Annual Meeting of the APS Division of Fluid Dynamics, APS Division of Fluid Dynamics (Fall) 2019, abstract id.H37.011

Ville :

Seattle

Pays :

Etats-Unis d'Amérique

Date de début de la manifestation scientifique :

2019-11-23

Date de publication :

2019-11

Discipline(s) HAL :

Physique [physics]/Physique [physics]/Dynamique des Fluides [physics.flu-dyn]

Résumé en anglais : [en]

The rotational dynamics of small anisotropic material particles (e . g . fibers or disks) in turbulent flows has been the focus of a series of recent studies. Experiments as well as numerical simulations have highlighted ...
Lire la suite >The rotational dynamics of small anisotropic material particles (e . g . fibers or disks) in turbulent flows has been the focus of a series of recent studies. Experiments as well as numerical simulations have highlighted their complex behavior, which is inherited from the non-trivial dynamics of the velocity gradient tensor along the particle trajectories. We report the investigation of orientation dynamics of neutrally buoyant anisotropic particles as they are advected in the Rayleigh-Benard convection by means of experiments and simulations. Compared with the homogeneous isotropic turbulence, the global rotation rate square for particles reveals a similar distribution whereas the averaged value as a function of aspect ratio shows a significant decrease. We propose a simple model to qualitatively understand the phenomenon. It is found that the large scale circulation significantly changes the flow topology into a bidimensional state so as to be responsible for the rotation rate variation.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Collections :

• Unité de Mécanique de Lille (UML) - ULR 7512

Source :

Harvested from HAL