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

200 papers

A suspension of swimming microorganisms often generates a large-scale convective pattern known as bioconvection. In contrast to the thermal Rayleigh-Benard system, recent experimental studies report an emergence of steady localized…

Fluid Dynamics · Physics 2024-06-25 Yoshiki Hiruta , Kenta Ishimoto

We present the results of a series of radiation-MHD simulations of a local patch of an accretion disk, with fixed vertical gravity profile but with different surface mass densities and a broad range of radiation to gas pressure ratios. Each…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Shigenobu Hirose , Omer Blaes , Julian H. Krolik

In this article, we continue the program started in our previous article of exploring an important class of thermodynamic systems from a geometric point of view. In order to model the time evolution of systems verifying the two laws of…

In the context of thermodynamics applied to our cosmological apparent horizon, we explicit in greater details our previous work which established the Friedmann Equations from projection of Hayward's Unified First Law. In particular, we show…

General Relativity and Quantum Cosmology · Physics 2015-02-17 Alexis Helou

We numerically study the Rayleigh-B\'enard (RB) convection in two-dimensional model emulsions confined between two parallel walls at fixed temperatures. The systems under study are heterogeneous, with finite-size droplets dispersed in a…

We study the conductive and convective states of phase-change of pure water in a rectangular container where two opposite walls are kept respectively at temperatures below and above the freezing point and all the other boundaries are…

Fluid Dynamics · Physics 2021-12-13 Ziqi Wang , Enrico Calzavarini , Chao Sun

We consider the effects of advection and radial gradients of pressure and radial drift velocity on the structure of optically thick accretion disks. We concentrate our efforts on highly viscous disks, $\alpha=1.0$, with large accretion…

Astrophysics · Physics 2007-05-23 I. V. Artemova , G. S. Bisnovatyi-Kogan , G. Bjoernsson , I. D. Novikov

A popular model for the circumstellar disks of Be stars is that of a geometrically thin disk with a density in the equatorial plane that drops as a power law of distance from the star. It is usually assumed that the vertical structure of…

Solar and Stellar Astrophysics · Physics 2009-07-24 T. A. A. Sigut , M. A. McGill , C. E. Jones

This paper is part of a bottom-up approach to gravitational thermodynamics that is guided by the axiomatic frameworks of equilibrium thermodynamics. We identify a novel form of the microcanonical distribution for systems in background…

General Relativity and Quantum Cosmology · Physics 2025-08-19 Eirini Sourtzinou , Charis Anastopoulos

Progress in the theory of stellar convection over the past decade is reviewed. The similarities and differences between convection in stellar envelopes and laboratory convection at high Rayleigh numbers are discussed. Direct numerical…

Astrophysics · Physics 2007-05-23 H. C. Spruit

Gravitational thermodynamics and gravitoscalar thermodynamics with $S^2 \times \mathbb{R}$ boundary geometry are investigated through the partition function, assuming that all Euclidean saddle point geometries contribute to the path…

General Relativity and Quantum Cosmology · Physics 2021-09-28 Shoichiro Miyashita

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

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 response of advection-dominated accretion disks to local disturbances is examined by one-dimensional numerical simulations. It is generally believed that advection-dominated disks are thermally stable. We, however, find that any…

Astrophysics · Physics 2009-10-28 T. Manmoto , M. Takeuchi , S. Mineshige , R. Matsumoto , H. Negoro

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

Boiling is an extremely effective way to promote heat transfer from a hot surface to a liquid due to several mechanisms many of which are not understood in quantitative detail. An important component of the overall process is that the…

The approach to the analysis of the dynamic of non-equilibrium open systems within the framework of the laws of classical mechanics on the example a hard-disks is offered. This approach was based on Hamilton and Liouville generalized…

Statistical Mechanics · Physics 2007-05-23 V. M. Somsikov

Previously we published a dynamical model (E. Brown and G. Ahlers, Phys. Fluids, 20, 075101 (2008)) for the large-scale-circulation (LSC) dynamics of Rayleigh-Benard convection in cylindrical containers. The model consists of a pair of…

Fluid Dynamics · Physics 2009-11-13 Eric Brown , Guenter Ahlers

(Abridged) We report results of three dimensional MHD simulations of global accretion disks threaded with weak vertical magnetic fields. We perform the simulations in the spherical coordinates with different temperature profiles and…

Earth and Planetary Astrophysics · Physics 2015-06-17 Takeru K. Suzuki , Shu-ichiro Inutsuka

We propose the concept of global temperature for spatially non-uniform heat conduction systems. With this novel quantity, we present an extended framework of thermodynamics for the whole system such that the fundamental relation of…

Statistical Mechanics · Physics 2019-10-23 Naoko Nakagawa , Shin-ichi Sasa