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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

Two-dimensional direct numerical simulations are conducted for convection sustained by uniform internal heating in a horizontal fluid layer. Top and bottom boundary temperatures are fixed and equal. Prandtl numbers range from 0.01 to 100,…

Fluid Dynamics · Physics 2015-03-13 David Goluskin , Edward A. Spiegel

We obtain an analytical bound on the mean vertical convective heat flux $\langle w T \rangle$ between two parallel boundaries driven by uniform internal heating. We consider two configurations, one with both boundaries held at the same…

Fluid Dynamics · Physics 2022-03-18 Anuj Kumar , Ali Arslan , Giovanni Fantuzzi , John Craske , Andrew Wynn

The mean vertical heat transport $\langle wT \rangle$ in convection between isothermal plates driven by uniform internal heating is investigated by means of rigorous bounds. These are obtained as a function of the Rayleigh number $R$ by…

Fluid Dynamics · Physics 2021-07-01 Ali Arslan , Giovanni Fantuzzi , John Craske , Andrew Wynn

Convection of an internally heated fluid, confined between top and bottom plates of equal temperature, is studied by direct numerical simulation in two and three dimensions. The unstably stratified upper region drives convection that…

Fluid Dynamics · Physics 2016-06-30 David Goluskin , Erwin P. van der Poel

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

We consider convection in an internally heated layer of fluid that is bounded below by a perfect insulator and above by a poor conductor. The poorly conducting boundary is modelled by a fixed heat flux. Using solely analytical methods, we…

Fluid Dynamics · Physics 2016-06-30 David Goluskin

We prove new bounds on the heat flux out of the bottom boundary, $\mathcal{F}_B$, for a fluid at infinite Prandtl number, heated internally between isothermal parallel plates under two kinematic boundary conditions. In uniform internally…

Fluid Dynamics · Physics 2024-03-22 Ali Arslan , Ruben E. Rojas

We investigate the influence of the thermal properties of the boundaries in turbulent Rayleigh-B\'enard convection on analytical upper bounds on convective heat transport. We model imperfectly conducting bounding plates in two ways: using…

Fluid Dynamics · Physics 2010-08-17 Ralf W. Wittenberg

We prove a new rigorous bound for the mean convective heat transport $\langle w T \rangle$, where $w$ and $T$ are the nondimensional vertical velocity and temperature, in internally heated convection between an insulating lower boundary and…

Fluid Dynamics · Physics 2023-06-22 Ali Arslan , Giovanni Fantuzzi , John Craske , Andrew Wynn

This work reviews basic features of both Rayleigh-B\'enard (RB) convection and internally heated (IH) convection, along with findings on IH convection from laboratory experiments and numerical simulations. In the first chapter, six…

Fluid Dynamics · Physics 2019-04-16 David Goluskin

Convection on geophysical and astrophysical scales is subject to rapid rotation and strong heating from within the domain. In studying the long-time behaviour of the solutions for such a system, energy identities fail to capture the effects…

Fluid Dynamics · Physics 2026-04-03 Yutong Zhang , Ali Arslan , Stefano Maffei , Andrew Jackson

We derive an improved rigorous bound on the space and time averaged temperature $<T>$ of an infinite Prandtl number Boussinesq fluid contained between isothermal no-slip boundaries thermally driven by uniform internal heating. A novel…

Fluid Dynamics · Physics 2015-05-27 Jared P. Whitehead , Charles R. Doering

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…

Laboratory experiments were conducted to study heat transport characteristics in a nonhomogeneously heated fluid annulus subjected to rotation along the vertical axis (z). The nonhomogeneous heating was obtained by imposing radial and…

Internally heated convection involves the transfer of heat by fluid motion between a distribution of sources and sinks. Focusing on the balanced case where the total heat added by the sources matches the heat taken away by the sinks, we…

Analysis of PDEs · Mathematics 2022-12-13 Binglin Song , Giovanni Fantuzzi , Ian Tobasco

A series of direct numerical simulations of Rayleigh-B\'enard convection, the flow in a fluid layer heated from below and cooled from above, were conducted to investigate the effect of mixed insulating and conducting boundary conditions on…

Results from direct numerical simulation for three-dimensional Rayleigh-B\'enard convection in samples of aspect ratio $\Gamma=0.23$ and $\Gamma=0.5$ up to Rayleigh number $Ra=2\times10^{12}$ are presented. The broad range of Prandtl…

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

Penetrative turbulence, which occurs in a convectively unstable fluid layer and penetrates into an adjacent, originally stably stratified layer, is numerically and theoretically analyzed. We chose the most relevant example, namely thermally…

Fluid Dynamics · Physics 2021-06-30 Qi Wang , Philipp Reiter , Detlef Lohse , Olga Shishkina
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