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Related papers: Large-scale circulations in a shear-free convectiv…

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Based on a mean-field theory of a non-rotating turbulent convection (Phys. Rev. E {\bf 66}, 066305, 2002), we perform mean-field simulations (MFS) of sheared convection which takes into account an effect of modification of the turbulent…

Fluid Dynamics · Physics 2024-07-16 A. Asulin , E. Tkachenko , N. Kleeorin , A. Levy , I. Rogachevskii

Formation of large-scale coherent structures in a turbulent convection via excitation of large-scale instability is studied. The redistribution of the turbulent heat flux due to non-uniform large-scale motions plays a crucial role in the…

Astrophysics · Physics 2008-11-26 T. Elperin , I. Golubev , N. Kleeorin , I. Rogachevskii

A new mean-field theory of turbulent convection is developed. This theory predicts the convective wind instability in a shear-free turbulent convection which causes formation of large-scale semi-organized fluid motions in the form of cells…

Astrophysics · Physics 2009-11-07 T. Elperin , N. Kleeorin , I. Rogachevskii , S. Zilitinkevich

We investigate properties of turbulence and turbulent transport of non-inertial particles described in terms of turbulent thermal diffusion in strongly inhomogeneous and anisotropic convection forced by two similar turbulence generators…

Fluid Dynamics · Physics 2025-12-17 E. Zarbib , E. Elmakies , O. Shildkrot , N. Kleeorin , A. Levy , I. Rogachevskii

We study an effect of large-scale coherent structures on global properties of turbulent convection in laboratory experiments in air flow in a rectangular chamber with aspect ratios $A \approx 2$ and $A\approx 4$ (with the Rayleigh numbers…

Fluid Dynamics · Physics 2015-05-13 M. Bukai , A. Eidelman , T. Elperin , N. Kleeorin , I. Rogachevskii , I. Sapir-Katiraie

We studied experimentally the effect of turbulent thermal diffusion in a multi-fan turbulence generator which produces a nearly homogeneous and isotropic flow with a small mean velocity. Using Particle Image Velocimetry and Image Processing…

Fluid Dynamics · Physics 2009-11-11 A. Eidelman , T. Elperin , N. Kleeorin , I. Rogachevskii , I. Sapir-Katiraie

We study turbulent flows in planar channels with unstable thermal stratification, using direct numerical simulations in a wide range of Reynolds and Rayleigh numbers and reaching flow conditions which are representative of asymptotic…

Fluid Dynamics · Physics 2017-06-28 Sergio Pirozzoli , Matteo Bernardini , Roberto Verzicco , Paolo Orlandi

We investigate experimentally phenomenon of turbulent thermal diffusion of micron-size solid particles in an inhomogeneous convective turbulence forced by one vertically-oriented oscillating grid in an air flow. This effect causes formation…

Fluid Dynamics · Physics 2024-04-19 E. Elmakies , O. Shildkrot , N. Kleeorin , A. Levy , I. Rogachevskii

Turbulent convection processes in nature are often found to be organized in a hierarchy of plume structures and flow patterns. The gradual aggregation of convection cells or granules to a supergranule which eventually fills the whole…

Fluid Dynamics · Physics 2021-03-16 Philipp P. Vieweg , Janet D. Scheel , Jörg Schumacher

We study experimentally and theoretically transition phenomena caused by the external forcing from Rayleigh-Benard convection with the large-scale circulation (LSC) to the limiting regime of unstably stratified turbulent flow without LSC…

Fluid Dynamics · Physics 2015-05-14 M. Bukai , A. Eidelman , T. Elperin , N. Kleeorin , I. Rogachevskii , I. Sapir-Katiraie

We present a numerical study of Rayleigh-B\'enard convection disturbed by a longitudinal wind. Our results show that under the action of the wind, the vertical heat flux through the cell initially decreases, due to the mechanism of…

Fluid Dynamics · Physics 2015-06-17 Andrea Scagliarini , Armann Gylfason , Federico Toschi

Turbulent thermal diffusion is a combined effect of the temperature stratified turbulence and inertia of small particles. It causes the appearance of a non-diffusive turbulent flux of particles in the direction of the turbulent heat flux.…

Fluid Dynamics · Physics 2018-05-24 G. Amir , N. Bar , A. Eidelman , T. Elperin , N. Kleeorin , I. Rogachevskii

Two types of spontaneous breaking of the space translational symmetry in distributed chaos have been considered for turbulent thermal convection at large values of Rayleigh number. First type is related to boundaries and second type is…

Fluid Dynamics · Physics 2016-10-19 A. Bershadskii

We investigated experimentally stably stratified turbulent flows in a lid driven cavity with a non-zero vertical mean temperature gradient in order to identify the parameters governing the mean and turbulent flows and to understand their…

Fluid Dynamics · Physics 2014-11-19 N. Cohen , A. Eidelman , T. Elperin , N. Kleeorin , I. Rogachevskii

Turbulent convection systems are known to give rise to prominent large scale circulation. At the same time, the `background' (or `small-scale') turbulence is also highly relevant and e.g. carries the majority of the heat transport in the…

Fluid Dynamics · Physics 2021-10-18 Pieter Berghout , Woutijn Johannes Baars , Dominik Krug

The multiscale flow structure in the solar convection zone - the coexistence of such features as the granules, mesogranules, supergranules and giant cells - has not yet been properly understood. Here, the possible role of one physical…

Solar and Stellar Astrophysics · Physics 2018-02-15 O. V. Shcheritsa , A. V. Getling , O. S. Mazhorova

Turbulence is an out-of-equilibrium flow state that is characterised by nonzero net fluxes of kinetic energy between different scales of the flow. These fluxes play a crucial role in the formation of characteristic flow structures in many…

Fluid Dynamics · Physics 2026-02-04 Youri H. Lemm , Xander M. de Wit , Rudie P. J. Kunnen

We consider a shear flow of a scale invariant homogeneous Gaussian random velocity field which does not depend on coordinates in the direction of the flow. We investigate a heat advection coming from a Gaussian random homogeneous source. We…

Fluid Dynamics · Physics 2009-11-11 Z. Haba

It is shown that helicity dynamics dominates spectral distribution of the velocity fluctuations in turbulent thermal convection at moderate and large values of the Rayleigh number (distributed chaos and scaling respectively). The…

Fluid Dynamics · Physics 2020-04-29 A. Bershadskii

We present the results of a very large aspect ratio (42.6) numerical simulation of fully compressible turbulent convection in a polytropic atmosphere, and focus on the properties of large-scale flows. Mesoscale patterns dominate the…

Astrophysics · Physics 2009-11-11 F. Rincon , F. Lignieres , M. Rieutord
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