English
Related papers

Related papers: Inclusion of turbulence in solar modeling

200 papers

We have constructed models for the sun at three stages of its evolution: a zero-age main sequence model, the present sun, and a subgiant model. For each model, the turbulent pressure and turbulent kinetic energy were calculated from 3-d…

Astrophysics · Physics 2007-05-23 P. Demarque , L. H. Li , F. J. Robinson , S. Sofia , Y. -C. Kim , K. L. Chan , D. B. Guenther

A 3D simulation of the upper part of the solar convective zone is used to derive constraints about the averaged and dynamic properties of solar turbulent convection. Theses constraints are then used to compute the acoustic energy supply…

Astrophysics · Physics 2007-05-23 R. Samadi , A. Nordlund , R. F. Stein , M. J. Goupil , I. Roxburgh

The goal of this research is to investigate how well various turbulence models can describe physical properties of the upper convective boundary layer of the Sun. An accurate modeling of the turbulence motions is necessary for understanding…

Astrophysics · Physics 2009-11-13 L. Jacoutot , A. G. Kosovichev , A. Wray , N. N. Mansour

The effects of turbulence on the mixing of gases and dust in the outer Solar nebula are examined using 3-D MHD calculations in the shearing-box approximation with vertical stratification. The turbulence is driven by the magneto-rotational…

Astrophysics · Physics 2009-11-13 N. J. Turner , K. Willacy , G. Bryden , H. W. Yorke

The first paper of this series established a linear stochastic wave equation for solar-like p-modes, correctly taking the effect of turbulence thereon into account. In this second paper, we aim at deriving simultaneous expressions for the…

Solar and Stellar Astrophysics · Physics 2022-08-31 J. Philidet , K. Belkacem , M. -J. Goupil

Differences between observed and theoretical eigenfrequencies of the Sun have characteristics which identify them as arising predominantly from properties of the oscillations in the vicinity of the solar surface: in the super-adiabatic,…

Acoustic power and oscillation amplitudes of radial oscillations computed for a solar model are compared with solar seismic observations. The oscillations are assumed stochastically excited by turbulence. The numerical computations are…

Astrophysics · Physics 2009-11-06 Reza Samadi , Marie-Jo Goupil , Yveline Lebreton

Solar p-mode oscillations exhibit a systematic offset towards higher frequencies due to shortcomings in the 1D stellar structure models, especially, the lack of turbulent pressure in the superadiabatic layers just below the optical surface,…

Solar and Stellar Astrophysics · Physics 2016-07-06 Zazralt Magic , Achim Weiss

We develop a 1D solar-wind model that includes separate energy equations for the electrons and protons, proton temperature anisotropy, collisional and collisionless heat flux, and an analytical treatment of low-frequency, reflection-driven,…

Solar and Stellar Astrophysics · Physics 2012-01-10 Benjamin D. G. Chandran , Timothy J. Dennis , Eliot Quataert , Stuart D. Bale

We study the evolution of turbulence in the solar wind by solving numerically the full 3D magneto-hydrodynamic (MHD) equations embedded in a radial mean wind. The corresponding equations (expanding box model or EBM) have been considered…

Solar and Stellar Astrophysics · Physics 2015-06-22 Yue Dong , Andrea Verdini , Roland Grappin

Aims. This series of papers aims at building a new formalism specifically tailored to study the impact of turbulence on the global modes of oscillation in solar-like stars. This first paper aims at deriving a linear wave equation that…

Solar and Stellar Astrophysics · Physics 2021-12-08 J. Philidet , K. Belkacem , M. -J. Goupil

The excitation rate P of solar p-modes is computed with a model of stochatic excitation which involves constraints on the averaged properties of the solar turbulence. These constraints are obtained from a 3D simulation. Resulting values for…

Astrophysics · Physics 2007-05-23 R. Samadi , M. J. Goupil , Y. Lebreton , A. Nordlund , F. Baudin

Although it is widely accepted that photospheric motions provide the energy source and that the magnetic field must play a key role in the process, the detailed mechanisms responsible for heating the Sun's corona and accelerating the solar…

Solar and Stellar Astrophysics · Physics 2016-01-12 Roberto Lionello , Marco Velli , Cooper Downs , Jon A. Linker , Zoran Mikić

With the recent results of helioseismology aboard SOHO, solar models are more and more constrained (Brun, Turck-Chieze and Morel 1998 (astro-ph/9806272)). New physical processes, mainly connected to macroscopic motions, must be introduced…

Astrophysics · Physics 2007-05-23 A. S. Brun , S. Turck-Chieze , J. P. Zahn

We adopted an unstructured hydrodynamical solver CharLES to the problem of global convection in the Sun. With the aim to investigate the properties of solar turbulent convection and reproduce differential rotation pattern. We performed…

Solar and Stellar Astrophysics · Physics 2014-12-24 Vyacheslav Olshevsky , Chunlei Liang , Frank Ham

A turbulent transport of radiation in the solar convective zone is investigated. The mean-field equation for the irradiation intensity is derived. It is shown that due to the turbulent effects, the effective penetration length of radiation…

Solar and Stellar Astrophysics · Physics 2022-03-01 I. Rogachevskii , N. Kleeorin

The space-borne missions have provided a wealth of highly accurate data. However, our inability to properly model the upper-most region of solar-like stars prevents us from making the best of these observations. This problem is called…

Solar and Stellar Astrophysics · Physics 2017-03-29 T. Sonoi , K. Belkacem , M. -A. Dupret , R. Samadi , H. -G. Ludwig , E. Caffau , B. Mosser

Low-frequency turbulence in the solar chromosphere remains poorly understood. We address 1) the sources of low-frequency turbulence that potentially heat the chromosphere, and 2) how turbulence is transported and dissipated throughout the…

In this paper, we aim to develop a predictive model for solar radial $p$-mode line profiles in the velocity spectrum. Unlike the approach favoured by prior studies, this model is not described by free parameters and we do not use fitting…

Solar and Stellar Astrophysics · Physics 2020-03-18 J. Philidet , K. Belkacem , R. Samadi , C. Barban , H. -G. Ludwig

State-of-the-art one-dimensional (1D) stellar evolution codes rely on simplifying assumptions, such as mixing length theory, in order to describe superadiabatic convection. As a result, 1D stellar structure models do not correctly recover…

Solar and Stellar Astrophysics · Physics 2019-08-07 Andreas Christ Sølvsten Jørgensen , Achim Weiss
‹ Prev 1 2 3 10 Next ›