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An important question in turbulent Rayleigh-B\'{e}nard convection (RBC) is the effectiveness of convective heat transport, which is conveniently described via the scaling of the Nusselt number (${\rm{Nu}}$) with the Rayleigh (${\rm{Ra}}$)…

Fluid Dynamics · Physics 2020-04-29 P. Urban , T. Králík , P. Hanzelka , V. Musilová , T. Věžník , D. Schmoranzer , L. Skrbek

We investigate the large-scale circulation (LSC) in a turbulent Rayleigh-B\'enard convection flow in a cubic closed convection cell by means of direct numerical simulations at a Rayleigh number $Ra=10^6$. The numerical studies are conducted…

Fluid Dynamics · Physics 2022-01-20 Priyanka Maity , Péter Koltai , Jörg Schumacher

Results from direct numerical simulations of vertical natural convection at Rayleigh numbers $1.0\times 10^5$-$1.0\times 10^9$ and Prandtl number $0.709$ support a generalised applicability of the Grossmann-Lohse (GL) theory, which was…

Fluid Dynamics · Physics 2018-06-21 Chong Shen Ng , Andrew Ooi , Detlef Lohse , Daniel Chung

Reservoir computing is applied to model the large-scale evolution and the resulting low-order turbulence statistics of a two-dimensional turbulent Rayleigh-B\'{e}nard convection flow at a Rayleigh number ${\rm Ra}=10^7$ and a Prandtl number…

Fluid Dynamics · Physics 2020-11-25 Sandeep Pandey , Jörg Schumacher

Based on mesoscale lattice Boltzmann numerical simulations, we characterize the Rayleigh-B\'enard (RB) convective dynamics of dispersions of liquid droplets in another liquid phase. Our numerical methodology allows us to modify the…

The kinetic energy balance in Rayleigh--B\'{e}nard convection is investigated for the Prandtl number range $0.01\le Pr \le 150$ and for fixed Rayleigh number $Ra=5\cdot10^{6}$. The kinetic energy balance is divided into a dissipation, a…

Fluid Dynamics · Physics 2023-07-19 Klaus Petschel , Stephan Stellmach , Michael Wilczek , Johannes Lülff , Ulli Hansen

We investigate by direct numerical simulation Rayleigh-B\'enard convection in a rotating rectangular cell with rotation vector and gravity perpendicular to each other. The flow is two dimensional near the onset of convection with convection…

Fluid Dynamics · Physics 2022-05-12 K. Lüdemann , A. Tilgner

Natural convection from a stack of isothermal solid horizontal cylinders has been investigated numerically in a three dimensional computational domain. Simulations were conducted in both laminar and turbulent flow regimes of Rayleigh number…

Fluid Dynamics · Physics 2019-05-15 Subhasisa Rath , Sukanta Kumar Dash

We use highly resolved numerical simulations to study turbulent Rayleigh-B\'enard convection in a cell with sinusoidally rough upper and lower surfaces in two dimensions for $Pr = 1$ and $Ra = \left[4 \times 10^6, 3 \times 10^9\right]$. By…

Fluid Dynamics · Physics 2017-03-08 Srikanth Toppaladoddi , Sauro Succi , John S. Wettlaufer

Turbulent Rayleigh-B\'enard convection displays a large-scale order in the form of rolls and cells on lengths larger than the layer height once the fluctuations of temperature and velocity are removed. These turbulent superstructures are…

Fluid Dynamics · Physics 2018-05-30 Ambrish Pandey , Janet D. Scheel , Jörg Schumacher

The heat transport and corresponding changes in the large-scale circulation (LSC) in turbulent Rayleigh-B\'{e}nard convection are studied by means of three-dimensional direct numerical simulations as a function of the aspect ratio $\Gamma$…

Fluid Dynamics · Physics 2010-07-07 Jorge Bailon-Cuba , Mohammad S. Emran , Joerg Schumacher

In this study we consider the effect of a horizontal magnetic field on the Rayleigh-B\'enard convection in a finite liquid metal layer contained in a cuboid vessel (200 \times 200 \times 40 mm^3). Laboratory experiments are performed for…

Fluid Dynamics · Physics 2020-12-07 J. C. Yang , T. Vogt , S. Eckert

In this paper we investigate two-dimensional (2D) Rayleigh-B\'enard convection using direct numerical simulation in Boussinesq fluids of Prandtl number $P = 6.8$ confined between thermally conducting plates. We show through the simulation…

Chaotic Dynamics · Physics 2008-12-05 Supriyo Pal , Krishna Kumar , Mahendra K. Verma , Daniele Carati , Arnab K. De , Vinayak Eswaran

We simulate numerically Boussinesq convection in non-rotating spherical shells for a fluid with a unity Prandtl number and Rayleigh numbers up to $10^9$. In this geometry, curvature and radial variations of the gravitationnal acceleration…

Fluid Dynamics · Physics 2015-10-28 T. Gastine , J. Wicht , J. M. Aurnou

Many natural and industrial turbulent flows are subjected to time-dependent boundary conditions. Despite being ubiquitous, the influence of temporal modulations (with frequency $f$) on global transport properties has hardly been studied.…

Fluid Dynamics · Physics 2020-10-14 Rui Yang , Kai Leong Chong , Qi Wang , Roberto Verzicco , Olga Shishkina , Detlef Lohse

We present high-precision experimental and numerical studies of the Nusselt number $Nu$ as functions of the Rayleigh number $Ra$ in geostrophic rotating convection with domain aspect ratio ${\Gamma}$ varying from 0.4 to 3.8 and the Ekman…

Fluid Dynamics · Physics 2021-08-04 Hao-Yuan Lu , Guang-Yu Ding , Jun-Qiang Shi , Ke-Qing Xia , Jin-Qiang Zhong

We analyse the nonlinear dynamics of the large scale flow in Rayleigh-B\'enard convection in a two-dimensional, rectangular geometry of aspect ratio $\Gamma$. We impose periodic and free-slip boundary conditions in the streamwise and…

Fluid Dynamics · Physics 2021-03-31 Philip Winchester , Vassilios Dallas , Peter D. Howell

Albeit laboratory experiments and numerical simulations have proven themselves successful in enhancing our understanding of long-living large-scale flow structures in horizontally extended Rayleigh-B\'enard convection, some discrepancies…

Fluid Dynamics · Physics 2025-02-12 Philipp Patrick Vieweg , Theo Käufer , Christian Cierpka , Jörg Schumacher

Many environmental flows arise due to natural convection at a vertical surface, from flows in buildings to dissolving ice faces at marine-terminating glaciers. We use three-dimensional direct numerical simulations of a vertical channel with…

Fluid Dynamics · Physics 2023-06-22 Christopher J. Howland , Chong Shen Ng , Roberto Verzicco , Detlef Lohse

The dissolution process of small (initial (equivalent) radius $R_0 < 1$ mm) long-chain alcohol (of various types) sessile droplets in water is studied, disentangling diffusive and convective contributions. The latter can arise for high…