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Related papers: Convection in a mushy-layer along a heated wall

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Convective motions in the deep layers of the solar convection zone are affected by rotation, making the convective heat transport latitude-dependent, but this is not the case in the top layers near the surface. We use the thermal wind…

Solar and Stellar Astrophysics · Physics 2021-02-24 Arnab Rai Choudhuri

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

Stably-stratified layers may be present at the top of the electrically-conducting fluid layers of many planets either because the temperature gradient is locally subadiabatic or because a stable composition gradient is maintained by the…

Earth and Planetary Astrophysics · Physics 2022-11-08 Celine Guervilly

We demonstrate the ability to experimentally measure fluctuations of the convective heat transfer coefficient at the wall in a turbulent boundary layer. For this, we measure two-dimensional fields of wall-temperature fluctuations beneath a…

Fluid Dynamics · Physics 2025-02-04 Firoozeh Foroozan , Andrea Ianiro , Stefano Discetti , Woutijn J. Baars

A new two-layer model has been proposed to study microscale heat transfer associated with a developing flow boundary layer. As an example, a cold, microscale film of liquid impinging on an isothermal hot, horizontal surface has been…

Fluid Dynamics · Physics 2014-03-18 Jian-Jun Shu

We investigate theoretically the nonlinear state of ideal straight rolls in the Rayleigh-B\'enard system of a fluid layer heated from below with a porous medium using a Galerkin method. Applying the Oberbeck-Boussinesq approximation, binary…

Fluid Dynamics · Physics 2015-05-14 Rudolf Umla , Matthias Augustin , Bjoern Huke , Manfred Luecke

This study shows that the turbulent velocities most strongly correlated with outer-scaled ($\delta$-scaled) wall-pressure fluctuations beneath a zero-pressure-gradient boundary layer reside within the logarithmic region. Even though…

Fluid Dynamics · Physics 2026-05-05 Rahul Deshpande , Abdelrahman Hassanein , Woutijn J. Baars

A theoretical model is developed for the forced convection film boiling phenomenon over a heated sphere moving vertically downwards in the water. Unprecedented to the previous analytical studies, this model accounts for the buoyancy effects…

Fluid Dynamics · Physics 2021-10-15 Rishabh Singh , Anikesh Pal , Santanu De

Our Sun exhibits strong convective dynamo action which results in magnetic flux bundles emerging through the stellar surface as magnetic spots. Global-scale dynamo action is believed to generate large-scale magnetic structures in the deep…

Solar and Stellar Astrophysics · Physics 2014-03-05 Nicholas J. Nelson , Mark S. Miesch

We investigate states of rapidly rotating Rayleigh-B\'enard convection in a cylindrical cell over a range of Rayleigh number $3\times10^5\leq Ra \leq 5\times10^{9}$ and Ekman number $10^{-6} \leq Ek \leq 10^{-4}$ for Prandtl number $Pr =…

Fluid Dynamics · Physics 2024-04-16 Xuan Zhang , Philipp Reiter , Olga Shishkina , Robert E. Ecke

Convection in rotating spherical geometries is an important physical process in planetary and stellar systems. Using continuation methods at low Prandtl number, we find both strong equatorially asymmetric and symmetric polar nonlinear…

Solar and Stellar Astrophysics · Physics 2019-07-17 F. Garcia , F. R. N. Chambers , A. L. Watts

We present the first hydrodynamic, multi-dimensional simulations of He-shell flash convection. Specifically, we investigate the properties of shell convection at a time immediately before the He- luminosity peak during the 15th thermal…

Astrophysics · Physics 2009-11-11 Falk Herwig , Bernd Freytag , Robert M. Hueckstaedt , Francis X. Timmes

We present three-dimensional direct numerical simulations of turbulent Rayleigh-B\'enard convection in a closed rectangular box whose width $L_y$ and length $L_x$ are 0.8 and 2.4 times the height $H$, respectively. The Rayleigh number $Ra$…

Fluid Dynamics · Physics 2026-05-05 Ambrish Pandey , Jörg Schumacher , Matteo Parsani , Katepalli R. Sreenivasan

To produce a vortex, a torque must be applied to the fluid. In viscous fluids, the torques that produce turbulent vortices result from the loss of symmetry of the stress tensor, once the viscous friction exceeds the shear stress resistance…

General Physics · Physics 2020-04-21 A. Paglietti

Convection-driven porous media flows are common in industrial processes and in nature. The multiscale and multiphase character of these systems and the inherent non-linear flow dynamics make convection in porous media a complex phenomenon.…

Fluid Dynamics · Physics 2024-08-02 Marco De Paoli

Supersonic pre-transitional boundary layers flowing over porous flat and concave surfaces are studied using numerical and asymptotic methods. The porous wall is composed of thin equally-spaced cylindrical microcavities. The flow is…

Fluid Dynamics · Physics 2023-06-29 Pierre Ricco , Ludovico Fossà

Based on a mean-field theory of a non-rotating turbulent convection (Phys. Rev. E {\bf 66}, 066305, 2002), we perform mean-field simulations (MFS) of sheared convection which takes into account an effect of modification of the turbulent…

Fluid Dynamics · Physics 2024-07-16 A. Asulin , E. Tkachenko , N. Kleeorin , A. Levy , I. Rogachevskii

Convection in planets and stars is predicted to occur in the "ultimate regime'' of diffusivity-free, rapidly rotating turbulence, in which flows are characteristically unaffected by viscous and thermal diffusion. Boundary layer diffusion,…

Fluid Dynamics · Physics 2025-04-21 Jewel A. Abbate , Yufan Xu , Tobias Vogt , Susanne Horn , Keith Julien , Jonathan M. Aurnou

It is argued that there are three distinct zones in a wall bounded turbulent flow field dominated by three completely different mechanisms: - An outer region where the velocity profile is determined by the pressure distribution - A highly…

Fluid Dynamics · Physics 2010-01-12 Trinh Khanh Tuoc

Turbulent convection models are thought to be good tools to deal with the convective overshooting in the stellar interior. However, they are too complex to be applied in calculations of stellar structure and evolution. In order to…

Solar and Stellar Astrophysics · Physics 2013-07-16 Q. S. Zhang , Y. Li