Applications of the k – ω Model in Stellar Evolutionary Models
Abstract
The k – ω model for turbulence was first proposed by Kolmogorov. A new k – ω model for stellar convection was developed by Li, which could reasonably describe turbulent convection not only in the convectively unstable zone, but also in the overshooting regions. We revised the k – ω model by improving several model assumptions (including the macrolength of turbulence, convective heat flux, and turbulent mixing diffusivity, etc.), making it applicable not only for convective envelopes, but also for convective cores. Eight parameters are introduced in the revised k – ω model. It should be noted that the Reynolds stress (turbulent pressure) is neglected in the equation of hydrostatic support. We applied it into solar models and 5 M {sub ⊙} stellar models to calibrate the eight model parameters, as well as to investigate the effects of the convective overshooting on the Sun and intermediate mass stellar models.
 Authors:
 Yunnan Observatories, Chinese Academy of Sciences, Kunming 650216 (China)
 Publication Date:
 OSTI Identifier:
 22663596
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal; Journal Volume: 841; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPUTERIZED SIMULATION; CONVECTION; EQUATIONS; HEAT; HEAT FLUX; HYDROSTATICS; REYNOLDS NUMBER; STAR EVOLUTION; STAR MODELS; STRESSES; SUN; TURBULENCE
Citation Formats
Li, Yan, Email: ly@ynao.ac.cn. Applications of the k – ω Model in Stellar Evolutionary Models. United States: N. p., 2017.
Web. doi:10.3847/15384357/AA6D4E.
Li, Yan, Email: ly@ynao.ac.cn. Applications of the k – ω Model in Stellar Evolutionary Models. United States. doi:10.3847/15384357/AA6D4E.
Li, Yan, Email: ly@ynao.ac.cn. 2017.
"Applications of the k – ω Model in Stellar Evolutionary Models". United States.
doi:10.3847/15384357/AA6D4E.
@article{osti_22663596,
title = {Applications of the k – ω Model in Stellar Evolutionary Models},
author = {Li, Yan, Email: ly@ynao.ac.cn},
abstractNote = {The k – ω model for turbulence was first proposed by Kolmogorov. A new k – ω model for stellar convection was developed by Li, which could reasonably describe turbulent convection not only in the convectively unstable zone, but also in the overshooting regions. We revised the k – ω model by improving several model assumptions (including the macrolength of turbulence, convective heat flux, and turbulent mixing diffusivity, etc.), making it applicable not only for convective envelopes, but also for convective cores. Eight parameters are introduced in the revised k – ω model. It should be noted that the Reynolds stress (turbulent pressure) is neglected in the equation of hydrostatic support. We applied it into solar models and 5 M {sub ⊙} stellar models to calibrate the eight model parameters, as well as to investigate the effects of the convective overshooting on the Sun and intermediate mass stellar models.},
doi = {10.3847/15384357/AA6D4E},
journal = {Astrophysical Journal},
number = 1,
volume = 841,
place = {United States},
year = 2017,
month = 5
}

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