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Related papers: Modeling the Near-Surface Shear Layer: Diffusion S…

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We use helioseismic data obtained over two solar cycles to determine whether there are changes in the near-surface shear layer (NSSL). We examine this by determining the radial gradient of the solar rotation rate. The radial gradient itself…

Solar and Stellar Astrophysics · Physics 2022-01-12 H. M. Antia , Sarbani Basu

Direct numerical simulations of fully-developed turbulent channel flows with wavy walls are undertaken. The wavy walls, skewed with respect to the mean flow direction, are introduced as a means of emulating a Spatial Stokes Layer (SSL)…

Fluid Dynamics · Physics 2018-03-05 Sacha Ghebali , Sergei I. Chernyshenko , Michael A. Leschziner

The multiscale flow structure in the solar convection zone - the coexistence of such features as the granules, mesogranules, supergranules and giant cells - has not yet been properly understood. Here, the possible role of one physical…

Solar and Stellar Astrophysics · Physics 2018-02-15 O. V. Shcheritsa , A. V. Getling , O. S. Mazhorova

Recent results from high-resolution solar granulation observations indicate the existence of a population of small granular cells that are smaller than 600 km in diameter. These small convective cells strongly contribute to the total area…

Solar and Stellar Astrophysics · Physics 2015-05-05 B. Lemmerer , D. Utz , A. Hanslmeier , A. Veronig , S. Thonhofer , H. Grimm-Strele , R. Kariyappa

In this work, we introduce a novel generative denoising diffusion model for synthesizing the Sun's three-dimensional coronal magnetic field, a complex and dynamic region characterized by evolving magnetic structures. Despite daily…

Solar and Stellar Astrophysics · Physics 2025-10-03 Daniel E. da Silva , Michael Kirk , Nat Mathews , Andrés Muñoz-Jaramillo

The discovery of the solar activity cycle was linked from the outset to the observation of the temporal variability of sunspots, which we know to be the result of complex processes associated with the dynamics of inner layers. Numerous…

Solar and Stellar Astrophysics · Physics 2025-03-04 Jean-Pierre Rozelot , Alexander Kosovichev , Irina Kitiashvili

Three-dimensional numerical simulations with CO5BOLD, a new radiation hydrodynamics code, result in a dynamic, thermally bifurcated model of the non-magnetic chromosphere of the quiet Sun. The 3-D model includes the middle and low…

Results of realistic simulations of solar surface convection on the scale of supergranules (96 Mm wide by 20 Mm deep) are presented. The simulations cover only 10% of the geometric depth of the solar convection zone, but half its pressure…

Astrophysics · Physics 2008-11-05 R. F. Stein , A. Nordlund , D. Georgobiani , D. Benson , W. Schaffenberger

Super-resolution (SR) techniques based on deep learning have recently emerged as a promising approach to enhance the spatial resolution of computational fluid dynamics simulations while containing computational cost. In this paper, we…

Fluid Dynamics · Physics 2026-04-13 Armin Sheidani , Michele Girfoglio , Annalisa Quaini , Gianluigi Rozza

We examine the role of small-scale granulation in helping to drive supergranulation and even larger scales of convection. The granulation is modeled as localized cooling events introduced at the upper boundary of a 3-D simulation of…

Solar and Stellar Astrophysics · Physics 2012-01-24 Neal Hurlburt , Marc DeRosa , Kyle Augustson , Juri Toomre

The interaction of plasma with magnetic field in the partially ionised solar atmosphere is frequently modelled via a single-fluid approximation, which is valid for the case of a strongly coupled collisional media, such as solar photosphere…

Solar and Stellar Astrophysics · Physics 2018-07-18 P. A. González-Morales , E. Khomenko , T. P. Downes , A. de Vicente

Helioseismology has revealed an increase in the rotation rate with depth in a thin ($\sim$30 Mm) near-surface layer. The normalized rotational shear in this layer is independent of latitude. This rotational state is shown to be a…

Solar and Stellar Astrophysics · Physics 2024-02-13 Leonid Kitchatinov

The formation of a thin current sheet in a magnetic quasi-separatrix layer (QSL) is investigated by means of numerical simulation using a simplified ideal, low-$\beta$, MHD model. The initial configuration and driving boundary conditions…

Plasma Physics · Physics 2014-10-27 Frederic Effenberger , Kay Thust , Lukas Arnold , Rainer Grauer , Jürgen Dreher

This report outlines the development of a B-spline--spectral numerical code for the simulation of convection flows. It allows changing the spatial resolution in all three coordinates as a function of depth, which is especially advantageous…

Astrophysics · Physics 2008-05-06 Thomas Hartlep , Nagi N. Mansour

Three-dimensional large eddy simulations of solar surface convection using realistic model physics are conducted. The thermal structure of convective motions into the upper radiative layers of the photosphere, the range of convection cell…

Astrophysics · Physics 2007-10-17 Sergey Ustyugov

Numerical 3D radiative (M)HD simulations of solar convection are used to understand the physical properties of the solar photosphere. To validate this approach, it is important to check that no excessive thermodynamic fluctuations arise as…

Solar and Stellar Astrophysics · Physics 2015-06-16 C. Beck , D. Fabbian , F. Moreno-Insertis , K. G. Puschmann , R. Rezaei

A complex InAs/CdSe/ZnSe Core/Shell1/Shell2 (CSS) structure is synthesized, where the intermediate CdSe buffer layer decreases strain between the InAs core and the ZnSe outer shell. This structure leads to significantly improved…

Applied Physics · Physics 2021-05-25 Assaf Aharoni , Taleb Mokari , Inna Popov , Uri Banin

We develop a multiscale simulation model for diffusion of solutes through porous triblock copolymer membranes. The approach combines two techniques: self-consistent field theory (SCFT) to predict the structure of the self-assembled,…

We introduce two new methods that are designed to improve the realism and utility of large, active region-scale 3D MHD models of the solar atmosphere. We apply these methods to RADMHD, a code capable of modeling the Sun's upper convection…

Solar and Stellar Astrophysics · Physics 2010-05-06 William P. Abbett , George H. Fisher

A recent third-order, essentially non-oscillatory central scheme to advance the equations of single-fluid magnetohydrodynamics (MHD) in time has been implemented into a new numerical code. This code operates on a 3-D Cartesian,…

Solar and Stellar Astrophysics · Physics 2012-04-18 Jens Kleimann , Andreas Kopp , Horst Fichtner , Rainer Grauer