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Related papers: Semiconvection: numerical simulations

200 papers

The double diffusive convection between two parallel plates is numerically studied for a series of parameters. The flow is driven by the salinity difference and stabilized by the thermal field. Our simulations are directly compared to…

The current understanding of the turbulent dissipation in stellar convective zones is based on the assumption that the turbulence follows Kolmogorov scaling. This assumption is valid for some cases in which the time frequency of the…

Astrophysics · Physics 2012-05-14 Kaloyan Penev , Joseph Barranco , Dimitar Sasselov

This paper is concerned with numerical solution of transport problems in heterogeneous porous media. A semi-discrete continuous-in-time formulation of the linear advection-diffusion equation is obtained by using a mixed hybrid finite…

Numerical Analysis · Mathematics 2021-10-05 Thi-Thao-Phuong Hoang

Inclined turbulent thermal convection by large Rayleigh numbers in extremely small-Prandtl-number fluids is studied based on results of both, measurements and high-resolution numerical simulations. The Prandtl number $Pr\approx0.0093$…

A bidisperse porous medium is one with two porosity scales. There are the usual pores known as macro pores but also cracks or fissures in the skeleton which give rise to micro pores. In this article we develop and analyse a model for…

Fluid Dynamics · Physics 2021-10-26 Patrick Dondl , Brian Straughan

A statistical analysis of the wall roughness effect is carried out to determine the impact of the shape uncertainty on the Poiseuille number and Nusselt number of laminar forced convection. The focus is on the fully developed regime in a…

Fluid Dynamics · Physics 2025-06-02 A. Barletta , M. Celli , P. V. Brandão

The two-phase mixing layer formed between parallel gas and liquid streams is an important fundamental problem in turbulent multiphase flows. The problem is relevant to many industrial applications and natural phenomena, such as air-blast…

Fluid Dynamics · Physics 2018-12-05 Y. Ling , D. Fuster , G. Tryggvason , S. Zaleski

Three-dimensional studies of convection in deep spherical shells have been used to test the hypothesis that the strong jet streams on Jupiter, Saturn, Uranus, and Neptune result from convection throughout the molecular envelopes. Due to…

Earth and Planetary Astrophysics · Physics 2015-05-20 Adam P. Showman , Yohai Kaspi , Glenn R. Flierl

Convective overshoot mixing is a critical ingredient of stellar structure models, but is treated in most cases by ad hoc extensions of the mixing-length theory for convection. Advanced theories which are both more physical and numerically…

Solar and Stellar Astrophysics · Physics 2022-11-16 Felix Ahlborn , Friedrich Kupka , Achim Weiss , Martin Flaskamp

The advection-diffusion equation can be approximated by a one-dimensional diffusion equation in Lagrangian coordinates along the directions of compression of fluid elements (the stable manifold). This result holds in any number of…

Chaotic Dynamics · Physics 2009-11-07 Jean-Luc Thiffeault

This work presents a detailed mathematical model combined with an innovative efficient numerical model to predict heat, air and moisture transfer through porous building materials. The model considers the transient effects of air transport…

Applied Physics · Physics 2020-02-20 Julien Berger , Denys Dutykh , Nathan Mendes , Bolatbek Rysbaiuly

We report on modelling in stellar astrophysics with the ANTARES code. First, we describe properties of turbulence in solar granulation as seen in high-resolution calculations. Then, we turn to the first 2D model of pulsation-convection…

Solar and Stellar Astrophysics · Physics 2015-05-19 Herbert J. Muthsam , Friedrich Kupka , Eva Mundprecht , Florian Zaussinger , Hannes Grimm-Strele , Natalie Happenhofer

Direct numerical simulations of a temporally-developing, low-speed, variable-density, turbulent, plane mixing layer are performed. The Navier-Stokes equations in the low-Mach number approximation are solved using a novel algorithm based on…

Fluid Dynamics · Physics 2017-10-04 Antonio Almagro , Manuel Garcia-Villalba , Oscar Flores

Based on multi-dimensional, multi-group, flux-limited-diffusion hydrodynamic simulations of core-collapse supernovae with the VULCAN/2D code, we study the physical conditions within and in the vicinity of the nascent protoneutron star…

Astrophysics · Physics 2009-11-13 L. Dessart , A. Burrows , E. Livne , C. D. Ott

We study the interaction between tides and convection in astrophysical bodies by analysing the effect of a homogeneous oscillatory shear on a fluid flow. This model can be taken to represent the interaction between a large-scale periodic…

Solar and Stellar Astrophysics · Physics 2015-06-03 Gordon I. Ogilvie , Geoffroy Lesur

The coupling between mass transfer and hydrodynamic phenomena in two-phase flow is not necessarily straightforward due to the different effects that can be encountered. The treatment of such coupling is complex and requires particular…

Fluid Dynamics · Physics 2024-12-19 Mirantsoa Aimé Rasolofomanana , Romain Le Tellier , Hervé Henry

I represent results three-dimensional numerical simulation of solar surface convection on scales local supergranulation with realistic model physics. I study thermal structure of convective motions in photosphere, the range of convection…

Astrophysics · Physics 2009-11-13 Sergey Ustyugov

In a number of geophysical or planetological settings (Earth's inner core, a silicate mantle crystallizing from a magma ocean, or an ice shell surrounding a deep water ocean) a convecting crystalline layer is in contact with a layer of its…

Geophysics · Physics 2013-03-20 Renaud Deguen

A coupled map lattice for convection is proposed, which consists of Eulerian and Lagrangian procedures. Simulations of the model not only reproduce a wide-range of phenomena in Rayleigh-B\'{e}nard convection experiments but also lead to…

chao-dyn · Physics 2015-06-24 Tatsuo Yanagita , Kunihiko Kaneko

The diffuse medium in and around galaxies can exist in a multi-phase state: small, cold gas clouds contributing significantly to the total mass embedded in pressure equilibrium with a hotter, more diffuse volume-filling component. Modeling…

Astrophysics of Galaxies · Physics 2022-12-28 Rainer Weinberger , Lars Hernquist