English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In this paper, we calibrate the coefficients for the one-dimensional Reynoldsstress model with the data generated from the three-dimensional numericalsimulations of upward overshooting in turbulent compressible convection. It hasbeen found that the calibrated convective and isotropic coefficients are almostthe same as those calibrated in the pure convection zone. However, thecalibrated diffusive coefficients differ significantly from those calibrated inthe pure convection zone. We suspect that the diffusive effect induced by theboundary is stronger than by the adjacent stable zone. We have checked thevalidity of the downgradient approximation. We find that the prediction of thedowngradient approximation on the third-order moments is unsatisfactory.However, the prediction on their derivatives is much better. It explains whythe performance of the Reynolds stress model is reasonable in application tothe real stars. With the calibrated coefficients, we have solved the full setof nonlocal turbulent equations on Reynolds stress model. We find that theReynolds stress model has successfully produced the thermal adjustment layerand turbulent dissipation layer, which were identified in the three-dimensionalnumerical simulations. We suggest to use the inflection point of theauto-correlation of temperature perturbation and the P\'eclet number as theindicators on measuring the extents of the thermal adjustment layer andturbulent dissipation layer, respectively. This result may offer a practicalguidance on the application of the Reynolds stress model in 1D stellarstructure and evolution models.

Upward Overshooting in Turbulent Compressible Convection. III. Calibrate Parameters for One-dimensional Reynolds Stress Model