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Related papers: Penetrative Convection at High Rayleigh Numbers

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We study the influence of thermal boundary conditions on large aspect ratio Rayleigh-B\'enard convection by a joint analysis of experimental and numerical data sets for a Prandl number $\mathrm{Pr = 7}$ and Rayleigh numbers $\mathrm{Ra =…

Fluid Dynamics · Physics 2023-09-15 Theo Käufer , Philipp P. Vieweg , Jörg Schumacher , Christian Cierpka

We simulate thermal convection in a two-dimensional square box using the no-slip condition on all boundaries, and isothermal bottom and top walls and adiabatic sidewalls. We choose 0.1 and 1 for the Prandtl number $Pr$ and vary the Rayleigh…

Fluid Dynamics · Physics 2025-07-23 Ambrish Pandey , Katepalli R. Sreenivasan

The progress in our understanding of several aspects of turbulent Rayleigh-Benard convection is reviewed. The focus is on the question of how the Nusselt number and the Reynolds number depend on the Rayleigh number Ra and the Prandtl number…

Fluid Dynamics · Physics 2015-05-13 Guenter Ahlers , Siegfried Grossmann , Detlef Lohse

We report the results of high resolution direct numerical simulations of two-dimensional Rayleigh-B\'enard convection for Rayleigh numbers up to $\Ra=10^{10}$ in order to study the influence of temperature boundary conditions on turbulent…

Fluid Dynamics · Physics 2009-11-13 Hans Johnston , Charles R. Doering

The boundary layer flow in a Rayleigh-B\'enard convection cell of rectangular shape has been visualized in this fluid dynamics video. The experiment has been undertaken in air at a Rayleigh number $Ra=1.3\times 10^{10}$ and a Prandtl number…

Fluid Dynamics · Physics 2012-09-28 Ronald du Puits , Johannes Rilk , Christian Resagk , André Thess

Convection in the metallic cores of terrestrial planets is likely to be subjected to lateral variations in heat flux through the outer boundary imposed by creeping flow in the overlying silicate mantles. Boundary anomalies can significantly…

Geophysics · Physics 2017-09-01 Jon E. Mound , Christopher J. Davies

Inclined turbulent thermal convection by large Rayleigh numbers in extremely small-Prandtl-number fluids is studied based on results of both, measurements and high-resolution numerical simulations. The Prandtl number $Pr\approx0.0093$…

This work investigates heat transport in rotating internally heated convection, for a horizontally periodic fluid between parallel plates under no-slip and isothermal boundary conditions. The main results are the proof of bounds on the mean…

Fluid Dynamics · Physics 2024-12-25 Ali Arslan

We report experimental results for heat-transport measurements, in the form of the Nusselt number \Nu, by turbulent Rayleigh-B\'enard convection in a cylindrical sample of aspect ratio $\Gamma \equiv D/L = 0.50$ ($D = 1.12$ m is the…

Fluid Dynamics · Physics 2015-06-04 Guenter Ahlers , Xiaozhou He , Denis Funfschilling , Eberhard Bodenschatz

We perform a two-dimensional numerical study on the thermal effect of porous media on global heat transport and flow structure in Rayleigh-B\'enard (RB) convection, focusing on the role of thermal conductivity $\lambda$ of porous media,…

Fluid Dynamics · Physics 2023-04-17 Jun Zhong , Shuang Liu , Chao Sun

New bounds are proven on the mean vertical convective heat transport, $\overline{\langle wT \rangle}$, for uniform internally heated (IH) convection in the limit of infinite Prandtl number. For fluid in a horizontally-periodic layer between…

Fluid Dynamics · Physics 2023-03-22 Ali Arslan , Giovanni Fantuzzi , John Craske , Andrew Wynn

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…

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

The boundary layer structure of the velocity and temperature fields in turbulent Rayleigh-Benard flows in closed cylindrical cells of unit aspect ratio is revisited from a transitional and turbulent viscous boundary layer perspective. When…

Fluid Dynamics · Physics 2016-12-30 Jörg Schumacher , Vinodh Bandaru , Ambrish Pandey , Janet D. Scheel

By tailoring the geometry of the upper boundary in turbulent Rayleigh-B\'enard convection we manipulate the boundary layer -- interior flow interaction, and examine the heat transport using the Lattice Boltzmann method. For fixed amplitude…

Fluid Dynamics · Physics 2015-09-14 Srikanth Toppaladoddi , Sauro Succi , John S. Wettlaufer

Numerical data for the heat transfer as a function of the Prandtl (Pr) and Rossby (Ro) numbers in turbulent rotating Rayleigh-Benard convection are presented for Rayleigh number Ra = 10^8. When Ro is fixed the heat transfer enhancement with…

Fluid Dynamics · Physics 2011-12-05 Richard J. A. M. Stevens , Herman J. H. Clercx , Detlef Lohse

We study the structure of the thermal boundary layer (BL) in Rayleigh-B\'enard convection for Prandtl number ($Pr$) 0.021 by conducting direct numerical simulations in a two-dimensional square box for Rayleigh numbers ($Ra$) up to $10^9$.…

Fluid Dynamics · Physics 2021-01-11 Ambrish Pandey

We study the navigation of a self-propelled inertial particle in two-dimensional Rayleigh--B\'enard convection at Prandtl number $Pr = 0.71$ and cell aspect ratio $\Gamma = 4$ for Rayleigh numbers $Ra$ ranging from $10^{7}$ to $10^{11}$. A…

Fluid Dynamics · Physics 2026-04-17 Ao Xu , Hua-Lin Wu , Ben-Rui Xu , Heng-Dong Xi

We study the evolution of a melting front between the solid and liquid phases of a pure incompressible material where fluid motions are driven by unstable temperature gradients. In a plane layer geometry, this can be seen as classical…

Fluid Dynamics · Physics 2019-01-15 Benjamin Favier , Jhaswantsing Purseed , Laurent Duchemin

Results from direct numerical simulations for three dimensional Rayleigh-Benard convection in a cylindrical cell of aspect ratio 1/2 and Pr=0.7 are presented. They span five decades of Ra from $2\times 10^6$ to $2 \times10^{11}$. Good…

Fluid Dynamics · Physics 2011-12-05 Richard J. A. M. Stevens , Roberto Verzicco , Detlef Lohse