Small-Peclet-number approximation for stellar turbulent mixing zones

Jean-Cédric Chkair, Olivier Soulard, Jérôme Griffond, and Xavier Blanc
Phys. Rev. E 102, 033111 – Published 18 September 2020

Abstract

The purpose of this work is to derive a small turbulent Péclet–small turbulent Mach number approximation for hydroradiative turbulent mixing zones encountered in stellar interiors where the radiative conductivity can overwhelms the turbulent transport. To this end, we proceed to an asymptotic analysis and determine orders of magnitude for the fluctuating temperature and pressure, as well as closed expressions for the fluctuating conduction and velocity divergence. The latter is used to extend a Reynolds stress model to the small-Péclet regime. Three-dimensional direct numerical simulations of radiative Rayleigh-Taylor turbulent mixing zones are performed, first, to validate the asymptotic predictions and, second, to validate their use in the Reynolds stress model.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
3 More
  • Received 24 June 2020
  • Accepted 7 August 2020

DOI:https://doi.org/10.1103/PhysRevE.102.033111

©2020 American Physical Society

Physics Subject Headings (PhySH)

Fluid DynamicsGravitation, Cosmology & Astrophysics

Authors & Affiliations

Jean-Cédric Chkair, Olivier Soulard, and Jérôme Griffond

  • CEA, DAM, DIF, F-91297 Arpajon, France

Xavier Blanc

  • Université de Paris, Sorbonne Université, CNRS, Laboratoire Jacques-Louis Lions, F-75013 Paris, France

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 102, Iss. 3 — September 2020

Reuse & Permissions
Access Options

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review E

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×