Two-dimensional simulations of solar-like models with artificially enhanced luminosity

Baraffe, I.; Pratt, J.; Vlaykov, Dimitar; Guillet, Thomas; Goffrey, T.; Saux, A. Le; Constantino, T.

doi:10.1051/0004-6361/202140441

Cited by 15 publications

(35 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Indeed, these modifications can increase the numerical stability of the simulation and accelerate the thermal relaxation. In a first study (Baraffe et al 2021, hereafter Paper I), we performed two-dimensional fully compressible time-implicit simulations of convection in a solarlike model using the MUSIC code. We analysed the impact of increasing the stellar luminosity and thermal diffusivity on convective penetration (or overshooting) at the base of the convective envelope of a solar-like model.…”

Section: Introductionmentioning

confidence: 99%

Two-dimensional simulations of solar-like models with artificially enhanced luminosity

Saux

Guillet

Baraffe

et al. 2022

A&A

Self Cite

View full text Add to dashboard Cite

Artificially increasing the luminosity and the thermal diffusivity of a model is a common tactic adopted in hydrodynamical simulations of stellar convection. In this work, we analyse the impact of these artificial modifications on the physical properties of stellar interiors and specifically on internal gravity waves. We perform two-dimensional simulations of solar-like stars with the MUSIC code. We compare three models with different luminosity enhancement factors to a reference model. The results confirm that properties of the waves are impacted by the artificial enhancement of the luminosity and thermal diffusivity. We find that an increase in the stellar luminosity yields a decrease in the bulk convective turnover timescale and an increase in the characteristic frequency of excitation of the internal waves. We also show that a higher energy input in a model, corresponding to a larger luminosity, results in higher energy in high frequency waves. Across our tests with the luminosity and thermal diffusivity enhanced together by up to a factor of 104, our results are consistent with theoretical predictions of radiative damping. Increasing the luminosity also has an impact on the amplitude of oscillatory motions across the convective boundary. One must use caution when interpreting studies of internal gravity waves based on hydrodynamical simulations with artificially enhanced luminosity.

show abstract

Section: Introductionmentioning

confidence: 99%

Two-dimensional simulations of solar-like models with artificially enhanced luminosity

Saux

Guillet

Baraffe

et al. 2022

A&A

Self Cite

View full text Add to dashboard Cite

show abstract

“…Note ho we ver that the convection zone is not precisely adiabatically stratified with super-adiabaticity reaching O (10 −2 ) close to the surface. A close analogue of this initial model has been used in Baraffe et al ( 2021 ) and Le Saux et al ( 2022 ) to study the effects of luminosity boosting. This requires minimizing the super-adiabaticity in the convection zone (so that stratification is not affected by the luminosity boosting).…”

Section: Description Of the Simulationsmentioning

confidence: 99%

“…The relaxation time-scales may be shortened by artificially boosting the stellar luminosity and thermal dif fusi vity. Ho we ver, running such simulations self-consistently requires that the convection zone be adiabatic, to a v oid changes in the temperature stratification due to the boosting (Baraffe et al 2021 ). It has also been shown that boosting can have a significant impact on the dynamics throughout the stellar interior (Baraffe et al 2021 ;Le Saux et al 2022 ).…”

mentioning

confidence: 99%

“…Ho we ver, running such simulations self-consistently requires that the convection zone be adiabatic, to a v oid changes in the temperature stratification due to the boosting (Baraffe et al 2021 ). It has also been shown that boosting can have a significant impact on the dynamics throughout the stellar interior (Baraffe et al 2021 ;Le Saux et al 2022 ). Therefore, in this study, we do not resort to boosted simulations and consider instead 2D models with realistic stellar luminosity co v ering a wide selection of radial truncations.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Impact of radial truncation on global 2D hydrodynamic simulations for a Sun-like model

Vlaykov

Baraffe

Constantino

et al. 2022

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

Stellar convection is a non-local process responsible for the transport of heat and chemical species. It can lead to enhanced mixing through convective overshooting and excitation of internal gravity waves (IGWs) at convective boundaries. The relationship between these processes is still not well understood and requires global hydrodynamic simulations to capture the important large-scale dynamics. The steep stratification in stellar interiors suggests that the radial extent of such simulations can affect the convection dynamics, the IGWs in the stably stratified radiative zone, and the depth of the overshooting layer. We investigate these effects using two-dimensional global simulations performed with the fully compressible stellar hydrodynamics code MUSIC. We compare eight different radial truncations of the same solar-like stellar model evolved over approximately 400 convective turnover times. We find that the location of the inner boundary has an insignificant effect on the convection dynamics, the convective overshooting and the travelling IGWs. We relate this to the background conditions at the lower convective boundary which are unaffected by the truncation, as long as a significantly deep radiative layer is included in the simulation domain. However, we find that extending the outer boundary by only a few percent of the stellar radius significantly increases the velocity and temperature perturbations in the convection zone, the overshooting depth, the power and the spectral slope of the IGWs. The effect is related to the background conditions at the outer boundary, which are determined in essence by the hydrostatic stratification and the given luminosity.

show abstract

“…Indeed, these modifications can increase the numerical stability of the simulation and accelerate the thermal relaxation. In a first study (Baraffe et al 2021, hereafter Paper I), we performed two-dimensional fully compressible time-implicit simulations of convection in a solar-like model using the MUSIC code. We analysed the impact of increasing the stellar luminosity and thermal diffusivity on convective penetration (or overshooting) at the base of the convective envelope of a solar-like model.…”

Section: Introductionmentioning

confidence: 99%

Two-dimensional simulations of solar-like models with artificially enhanced luminosity. II. Impact on internal gravity waves

Saux,

Guillet,

Baraffe

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

Artificially increasing the luminosity and the thermal diffusivity of a model is a common tactic adopted in hydrodynamical simulations of stellar convection. In this work, we analyse the impact of these artificial modifications on the physical properties of stellar interiors and specifically on internal gravity waves. We perform two-dimensional simulations of solar-like stars with the MUSIC code. We compare three models with different luminosity enhancement factors to a reference model. The results confirm that properties of the waves are impacted by the artificial enhancement of the luminosity and thermal diffusivity. We find that an increase in the stellar luminosity yields a decrease in the bulk convective turnover timescale and an increase in the characteristic frequency of excitation of the internal waves. We also show that a higher energy input in a model, corresponding to a larger luminosity, results in higher energy in high frequency waves. Across our tests with the luminosity and thermal diffusivity enhanced together by up to a factor of 10 4 , our results are consistent with theoretical predictions of radiative damping. Increasing the luminosity also has an impact on the amplitude of oscillatory motions across the convective boundary. One must use caution when interpreting studies of internal gravity waves based on hydrodynamical simulations with artificially enhanced luminosity.

show abstract

Two-dimensional simulations of solar-like models with artificially enhanced luminosity

Cited by 15 publications

References 42 publications

Two-dimensional simulations of solar-like models with artificially enhanced luminosity

Two-dimensional simulations of solar-like models with artificially enhanced luminosity

Impact of radial truncation on global 2D hydrodynamic simulations for a Sun-like model

Two-dimensional simulations of solar-like models with artificially enhanced luminosity. II. Impact on internal gravity waves

Contact Info

Product

Resources

About