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Related papers: Rayleigh-Benard convection in a hard disk system

200 papers

In the classic picture of standard thin accretion disks, the viscous heating is balanced by the radiative cooling through the diffusion process, and the radiation-pressure-dominated inner disk suffers convective instability. However, recent…

High Energy Astrophysical Phenomena · Physics 2017-05-03 Hong-Yu Gong , Wei-Min Gu

Cold accretion disks such as those in star-forming systems, quiescent cataclysmic variables, and some active galactic nuclei, are expected to have neutral gas which does not couple well to magnetic fields. The turbulent viscosity in such…

Astrophysics · Physics 2009-11-10 Banibrata Mukhopadhyay , Niayesh Afshordi , Ramesh Narayan

In this manuscript, it is analysed the onset and evolution of natural convection of an incompressible fluid between spherical shells. The shells are kept at a fixed temperature difference and aspect ratio, and the Rayleigh-Benard convection…

Fluid Dynamics · Physics 2023-09-07 Luca Santelli , Guiquan Wang , Richard J. A. M. Stevens , Roberto Verzicco

We investigate properties of turbulence and turbulent transport of non-inertial particles described in terms of turbulent thermal diffusion in strongly inhomogeneous and anisotropic convection forced by two similar turbulence generators…

Fluid Dynamics · Physics 2025-12-17 E. Zarbib , E. Elmakies , O. Shildkrot , N. Kleeorin , A. Levy , I. Rogachevskii

Turbulent viscosity is frequently used in accretion disk theory to replace the microphysical viscosity in order to accomodate the observational need for in- stabilities in disks that lead to enhanced transport. However, simply replacing the…

Astrophysics · Physics 2015-05-13 Alexander Hubbard , Eric G. Blackman

Rotating turbulent convection occurs ubiquitously in natural convective systems encompassing planetary cores, oceans, and atmospheres, as well as in many industrial applications. While the global heat and mass transfer of water-like…

Fluid Dynamics · Physics 2024-10-08 Yufan Xu , Jewel Abbate , Cy David , Tobias Vogt , Jonathan Aurnou

A certain appeal to the alpha model for turbulence and related viscosity in accretion disks was that one scales the Reynolds stresses simply on the thermal pressure, assuming that turbulence driven by a certain mechanism will attain a…

Earth and Planetary Astrophysics · Physics 2021-09-22 Natascha Manger , Thomas Pfeil , Hubert Klahr

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

We study Rayleigh-Benard convection in the high-Rayleigh-number and high-Prandtl-number regime, i.e., we consider a fluid in a container that is exposed to strong heating of the bottom and cooling of the top plate in the absence of inertia…

Analysis of PDEs · Mathematics 2015-06-12 Christian Seis

The hard-disk model plays a role of touchstone for testing and developing the transport theory. By large scale molecular dynamics simulations of this model, three important autocorrelation functions, and as a result the corresponding…

Statistical Mechanics · Physics 2016-05-24 Hanqing Zhao , Hong Zhao

We theoretically prove the existence in granular fluids of a thermal convection that is inherent, in the sense that is always present and has no thermal gradient threshold (convection occurs for all finite values of the Rayleigh number).…

Soft Condensed Matter · Physics 2018-12-03 F. Vega Reyes , A. Puglisi , G. Pontuale , A. Gnoli

Equilibrium thermodynamics is grounded in the law of energy conservation, with a specific focus on how systems exchange energy with their environment during transitions between equilibrium states. These transitions are typically…

Statistical Mechanics · Physics 2024-08-19 Karol Makuch

Non-isothermal particles suspended in a fluid lead to complex interactions -- the particles respond to changes in the fluid flow, which in turn is modified by their temperature anomaly. Here, we perform a novel proof-of-concept numerical…

Fluid Dynamics · Physics 2022-12-06 Lokahith Agasthya , Andreas Bartel , Luca Biferale , Matthias Ehrhardt , Federico Toschi

We consider the accretion process in a disk with magnetic fields that are dragged in from the interstellar medium by gravitational collapse. Two diffusive processes are at work in the system: (1) "viscous" torques exerted by turbulent and…

We describe results of computer simulations of steady state heat transport in a fluid of hard discs undergoing both elastic interparticle collisions and velocity randomizing collisions which do not conserve momentum. The system consists of…

Statistical Mechanics · Physics 2020-06-24 Pedro L. Garrido , Joel L. Lebowitz

The Navier-Stokes equation driven by heat conduction is studied. As a prototype we consider Rayleigh-B\'enard convection, in the Boussinesq approximation. Under a large aspect ratio assumption, which is the case in Rayleigh-B\'enard…

Analysis of PDEs · Mathematics 2015-06-26 Björn Birnir , Nils Svanstedt

Context: A radial temperature gradient together with an inhomogeneous radial electric field gradient is applied to a dielectric fluid confined in a vertical cylindrical annulus inducing thermal electro-hydrodynamic convection. Aims:…

Our goal is to investigate fundamental properties of the system of internally cooled convection. The system consists of an upward thermal flux at the lower boundary, a mean temperature lapse-rate and a constant cooling term in the bulk with…

Fluid Dynamics · Physics 2024-04-09 Lokahith Agasthya , Caroline Muller

Bifurcation properties, stability behavior, dynamics, and the heat transfer of convection structures in a horizontal fluid layer that is driven away from thermal equilibrium by imposing a vertical temperature difference are compared with…

Pattern Formation and Solitons · Physics 2009-11-11 P. Matura , M. Luecke

The research is devoted to the stability of convective flow in a nonuniformly rotating layer of an electrically conducting fluid in a spiral magnetic field. The stationary and oscillatory modes of magnetic convection are considered…

Plasma Physics · Physics 2019-05-15 M. I. Kopp , A. V. Tur , V. V. Yanovsky