HUNTING FOR GIANT CELLS IN DEEP STELLAR CONVECTIVE ZONES USING WAVELET ANALYSIS [PDF]
The Astrophysical Journal, 2011 We study the influence of stratification on stellar turbulent convection near the stellar surface and in depth by carrying out 3D high resolution hydrodynamic simulations with the ASH code. Four simulations with different radial density contrast corresponding to different aspect ratio for the same underlying 4 Myr $0.7 M_\odot$ pre-main sequence star ...
Bessolaz, N. & Brun, A. S.
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27. On meridional circulations in stellar convective zones [PDF]
Symposium - International Astronomical Union, 1958 It is shown in outline by a discussion of the equation of motion in all its components and by taking regard of the geometrical properties of turbulent exchange, that in general the state of pure rotation (without meridional circulations) is not a possible stationary state of motion for convective zones of stars.
L. Biermann
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Linear Convective Modes and the Energy Transport in Stellar Convection Zones
The Astrophysical Journal, 1973 Model stars whose convection zones had been prepared in accordance with the standard mixing-length theory were used as a basis for the computation of unstable convective modes. It was found that no superposition of statistically independent, nonviscous, adiabatic, convective modes can reproduce the radial dependence of the convective flux of the model.
M. H. Hart
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Metallicity dependence of turbulent pressure and macroturbulence in stellar envelopes [PDF]
, 2016 Macroturbulence, introduced as a fudge to reproduce the width and shape of stellar absorption lines, reflects gas motions in stellar atmospheres. While in cool stars, it is thought to be caused by convection zones immediately beneath the stellar surface,
Castro, Norberto +5 more
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The Run of Superadiabaticity in Stellar Convection Zones. I. The Sun [PDF]
The Astrophysical Journal, 1997 The effect of adjustments to the superadiabatic layer (SAL) in a model of the Sun on the p-mode oscillation frequencies has been studied. Numerical simulations of solar convection by Kim and coworkers have shown that the usual mixing length approximation (MLA) overestimates the convective efficiency in the SAL.
Demarque, P. +2 more
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Convection Theory and Relevant Problems in Stellar Structure, Evolution, and Pulsational Stability I Convection Theory and Structure of Convection Zone and Stellar Evolution [PDF]
Frontiers in Astronomy and Space Sciences, 2021 A non-local and time-dependent theory of convection was briefly described. This theory was used to calculate the structure of solar convection zones, the evolution of massive stars, lithium depletion in the atmosphere of the Sun and late-type dwarfs, and stellar oscillations (in Part Ⅱ).
D. Xiong
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Prandtl number dependence of stellar convection: Flow statistics and convective energy transport [PDF]
Astronomy & Astrophysics, 2021 Context. The ratio of kinematic viscosity to thermal di ff usivity, the Prandtl number, is much smaller than unity in stellar convection zones. Aims.
P. J. Käpylä
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Stellar Convective Penetration: Parameterized Theory and Dynamical Simulations [PDF]
Astrophysical Journal, 2021 Most stars host convection zones in which heat is transported directly by fluid motion, but the behavior of convective boundaries is not well-understood.
E. H. Anders +3 more
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Calibration of the convective parameters in stellar pulsation hydrocodes [PDF]
Monthly notices of the Royal Astronomical Society, 2023 Despite the appearance of two- and three-dimensional models thanks to the rapid growth of computing performance, numerical hydrocodes used to model radial stellar pulsations still apply a one-dimensional stellar envelope model without any realistic ...
G. Kovács, J. Nuspl, R. Szabó
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Dynamical tide in stellar radiative zones. General formalism and evolution for low-mass stars [PDF]
Astronomy & Astrophysics, 2021 [Abridged] Most exoplanets detected so far are close-in planets, which are likely to be affected by tidal dissipation in their host star. To get a complete picture of the evolution of star-planet systems one needs to consider the impact of tides within ...
J. Ahuir, S. Mathis, L. Amard
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