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Related papers: Periodically modulated thermal convection

200 papers

To understand how internal flow structures manifest themselves in the global heat transfer, we study the correlation between different flow modes and the instantaneous Nusselt number ($Nu$) in a two-dimensional square Rayleigh-B\'enard…

Fluid Dynamics · Physics 2020-10-09 Ao Xu , Xin Chen , Feng Wang , Heng-Dong Xi

We prove the first rigorous bound on the heat transfer for three-dimensional Rayleigh-B\'enard convection of finite-Prandtl-number fluids between free-slip boundaries with an imposed heat flux. Using the auxiliary functional method with a…

Fluid Dynamics · Physics 2018-04-11 Giovanni Fantuzzi

Melting and, conversely, solidification processes in the presence of convection are key to many geophysical problems. An essential question related to these phenomena concerns the estimation of the (time-evolving) melting rate, which is…

The effect of various velocity boundary condition is studied in two-dimensional Rayleigh-B\'enard convection. Combinations of no-slip, stress-free and periodic boundary conditions are used on both the sidewalls and the horizontal plates.…

Fluid Dynamics · Physics 2015-01-09 Erwin P. van der Poel , Rodolfo Ostilla Mónico , Roberto Verzicco , Detlef Lohse

We report on the transition between two regimes of heat transport in a radiatively driven convection experiment, where a fluid gets heated up within a tunable heating length $\ell$ in the vicinity of the bottom of the tank. The first regime…

Fluid Dynamics · Physics 2020-10-22 V. Bouillaut , S. Lepot , S. Aumaître , B. Gallet

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

The dynamics of heat transfer in a model system of Rayleigh-B\'enard (RB) convection reduced to its essential, here dubbed Burgers-Rayleigh-B\'enard (BRB), is studied. The system is spatially one-dimensional, the flow field is compressible…

Fluid Dynamics · Physics 2023-07-04 Enrico Calzavarini , Silvia C. Hirata

In this paper, we extend Grossmann and Lohse's (GL) model [Phys. Rev. Lett. {\bf 86}, 3316 (2001)] for the predictions of Reynolds number (Re) and Nusselt number (Nu) in turbulent Rayleigh-B\'{e}nard convection (RBC). Towards this…

Fluid Dynamics · Physics 2021-01-12 Shashwat Bhattacharya , Mahendra K. Verma , Ravi Samtaney

This study explores heat and turbulent modulation in three-dimensional multiphase Rayleigh-B\'enard convection using direct numerical simulations. Two immiscible fluids with identical reference density undergo systematic variations in…

Fluid Dynamics · Physics 2024-08-26 Abbas Moradi Bilondi , Nicolò Scapin , Luca Brandt , Parisa Mirbod

We report an experimental investigation of turbulent Rayleigh-Benard convection in a rectangular cell of large aspect ratio ($\Gamma = 10$) over the Rayleigh number range $5.4\times10^7 \le Ra \le 7.2\times10^9$ and Prandtl number range…

Fluid Dynamics · Physics 2026-02-23 Yi-Zhen Li , Jun-Jie Huo , Xin Chen , Heng-Dong Xi

The turbulence statistics of the intermittent region in a supersonic turbulent boundary layer are studied by direct numerical simulation. Recently, Kwon et al. (2016) have shown that this intermittent behavior, consisting of the coexistence…

Fluid Dynamics · Physics 2017-10-04 Xiaoshuai Wu , Jianhan Liang , Yuxin Zhao , Marc Avila

We report the statistical properties of temperature and thermal energy dissipation rate in low-Prandtl number turbulent Rayleigh-B\'enard convection. High resolution two-dimensional direct numerical simulations were carried out for the…

Fluid Dynamics · Physics 2019-12-12 Ao Xu , Le Shi , Heng-Dong Xi

We numerically investigate the structures of the near-plate temperature profiles close to the bottom and top plates of turbulent Rayleigh-B\'{e}nard flow in a cylindrical sample at Rayleigh numbers Ra=10^8 to Ra=2\times10^{12} and Prandtl…

In turbulent Rayleigh-B\'{e}nard (RB) convection, a transition to the so-called ultimate regime, in which the boundary layers (BL) are of turbulent type, has been postulated. Indeed, at very large Rayleigh number $Ra \approx…

Fluid Dynamics · Physics 2018-08-15 Dominik Krug , Xiaojue Zhu , Daniel Chung , Ivan Marusic , Roberto Verzicco , Detlef Lohse

We study rotating homogeneous turbulent convection forced by a mean vertical temperature gradient by means of direct numerical simulations (DNS) in the Boussinesq approximation in a rotating frame. In the absence of rotationour results are…

Fluid Dynamics · Physics 2019-10-30 Francesco Toselli , Stefano Musacchio , Guido Boffetta

The aim of this paper is to contribute to the understanding and to model the processes controlling the amplitude of the wind of Rayleigh-Benard convection. We analyze results from direct simulation of an L/H = 4 aspect-ratio domain with…

Fluid Dynamics · Physics 2009-09-29 Maarten van Reeuwijk , Harm J. J. Jonker , Kemo Hanjalic

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

In thermal convection, roughness is often used as a means to enhance heat transport, expressed in Nusselt number. Yet there is no consensus on whether the Nusselt vs. Rayleigh number scaling exponent ($\mathrm{Nu} \sim \mathrm{Ra}^\beta$)…

Fluid Dynamics · Physics 2017-10-18 Xiaojue Zhu , Richard J. A. M. Stevens , Roberto Verzicco , Detlef Lohse

The impact of variable material properties, such as temperature-dependent thermal conductivity and dynamical viscosity, on the dynamics of a fully compressible turbulent convection flow beyond the anelastic limit are studied in the present…

Fluid Dynamics · Physics 2024-07-30 John Panickacheril John , Jörg Schumacher

Turbulent convection in the interiors of the Sun and the Earth occurs at high Rayleigh numbers $Ra$, low Prandtl numbers $Pr$, and different levels of rotation rates. To understand the combined effects better, we study rotating turbulent…

Fluid Dynamics · Physics 2024-11-20 Ambrish Pandey , Katepalli R. Sreenivasan