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Turbulent superstructures in horizontally extended three-dimensional Rayleigh-B\'enard convection flows are investigated in controlled laboratory experiments in water at Prandtl number $Pr = 7$. A Rayleigh-B\'enard cell with square…

Fluid Dynamics · Physics 2022-08-03 Sebastian Moller , Theo Käufer , Ambrish Pandey , Jörg Schumacher , Christian Cierpka

Recent findings suggest that wall-bounded turbulent flow can take different statistically stationary turbulent states, with different transport properties, even for the very same values of the control parameters. What state the system takes…

Fluid Dynamics · Physics 2020-08-19 Qi Wang , Roberto Verzicco , Detlef Lohse , Olga Shishkina

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

Rayleigh-B\'enard convection, i.e. the flow of a fluid between two parallel plates that is driven by a temperature gradient, is an idealised setup to study thermal convection. Of special interest are the statistics of the turbulent…

Rayleigh-Benard convection in a rotating spherical shell provides a simplified model for convective dynamics of planetary and stellar interiors. In this study, we build more than 200 numerical models of rotating convection in a spherical…

Fluid Dynamics · Physics 2025-08-14 Wei Fan , Qi Wang , Yufeng Lin

The corner roll (CR) in the Rayleigh-B\'{e}nard (RB) convection accounts for the behaviors of heat transport and convection flow at the corner. Streamlines of the three-dimensional direct numerical simulations for $10^8<Ra<5\times10^9$ show…

Fluid Dynamics · Physics 2019-10-08 Wen-Feng Zhou , Jun Chen

Here we summarize the results from our direct numerical simulations (DNS) and experimental measurements on rotating Rayleigh-B\'enard (RB) convection. Our experiments and simulations are performed in cylindrical samples with an aspect ratio…

Fluid Dynamics · Physics 2013-06-21 Richard J. A. M. Stevens , Herman Clercx , Detlef Lohse

We introduce a low-order dynamical system to describe thermal convection in an annular domain. The model derives systematically from a Fourier-Laurent truncation of the governing Navier-Stokes Boussinesq equations and accounts for spatial…

Fluid Dynamics · Physics 2024-11-20 Nicholas J. Moore , Jinzi Mac Huang

One prominent feature in the atmospheres of Jupiter and Saturn is the appearance of large-scale vortices. However, the sustaining mechanism of these large-scale vortices remains unclear. One possible mechanism is that these large-scale…

Fluid Dynamics · Physics 2021-09-30 Tao Cai

Various recent experiments hint at a geometry dependence of scaling relations in Rayleigh-B\'enard convection. Aspect ratio and shape dependences have been found. In this paper a mechanism is offered which can account for such dependences.…

Chaotic Dynamics · Physics 2009-11-07 Siegfried Grossmann , Detlef Lohse

We experimentally study the turbulent flow between two coaxial and independently rotating cylinders. We determined the scaling of the torque with Reynolds numbers at various angular velocity ratios (Rotation numbers), and the behaviour of…

Fluid Dynamics · Physics 2010-06-08 Florent Ravelet , Rene Delfos , Jerry Westerweel

We perform direct numerical simulations of wall sheared Rayleigh-B\'enard (RB) convection for Rayleigh numbers up to $Ra=10^8$, Prandtl number unity, and wall shear Reynolds numbers up to $Re_w=10000$. Using the Monin-Obukhov length…

A data-driven turbulence model for coarse-grained numerical simulations of two-dimensional Rayleigh-B\'enard convection is proposed. The model starts from high-fidelity data and is based on adjusting the Fourier coefficients of the…

Fluid Dynamics · Physics 2024-02-08 Sagy Ephrati , Paolo Cifani , Bernard Geurts

We investigate the large-scale circulation (LSC) of turbulent Rayleigh-B\'enard convection in a large box of aspect ratio $\Gamma =32$ for Rayleigh numbers up to $Ra=10^9$ and at a fixed Prandtl number $Pr=1$. A conditional averaging…

Possibility of asymmetric square convection is investigated numerically using a few mode Lorenz-like model for thermal convection in Boussinesq fluids confined between two stress free and conducting flat boundaries. For relatively large…

Pattern Formation and Solitons · Physics 2009-10-31 Alaka Das , Ujjal Ghosal , Krishna Kumar

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

We measured Reynolds numbers R_e of turbulent Rayleigh-Benard convection over the Rayleigh-number range 2 times 10^8 < R < 10^11 and Prandtl-number range 3.3 < sigma < 29 for cylindrical samples of aspect ratio Gamma = 1. For R < R_c = 3…

Fluid Dynamics · Physics 2007-05-23 Guenter Ahlers , Eric Brown , Denis Funfschilling , Alexei Nikolaenko

A numerical investigation of an asymptotically reduced model for quasi-geostrophic Rayleigh-B\'enard convection is conducted in which the depth-averaged flows are numerically suppressed by modifying the governing equations. The Reynolds…

Fluid Dynamics · Physics 2023-08-23 Tobias G. Oliver , Adrienne S. Jacobi , Keith Julien , Michael A. Calkins

We numerically study the propagation of reacting fronts in a shallow and horizontal layer of fluid with solutal feedback and in the presence of a thermally driven flow field of counter-rotating convection rolls. We solve the Boussinesq…

Fluid Dynamics · Physics 2020-04-01 S. Mukherjee , M. R. Paul

Turbulent superstructures, i.e. large-scale flow structures in turbulent flows, play a crucial role in many geo- and astrophysical settings. In turbulent Rayleigh-B\'{e}nard convection, for example, horizontally extended coherent…

Fluid Dynamics · Physics 2020-03-30 Gerrit Green , Dimitar G. Vlaykov , Juan Pedro Mellado , Michael Wilczek