Plumes in Stellar Convection Zones.
Abstract
All numerical simulations of compressible convection reveal the presence of strong downwards directed flows. Thanks to helioseismology, such plumes have now been detected also at the top of the solar convection zone, on super- granular scales. Their properties may be crudely described by adopting Taylor's turbulent entrainment hypothesis, whose validity is well established under various conditions. Using this model, one finds that the strong density stratification does not prevent the plumes from traversing the whole convection zone, and that they carry upwards a net energy flux (Rieutord & Zahn 1995). They penetrate to some extent in the adjacent stable region, where they establish a nearly adiabatic stratification. These plumes have a strong impact on the dynamics of stellar convection zones, and they play probably a key role in the dynamo mechanism.
- Publication:
-
Astrophysical Turbulence and Convection
- Pub Date:
- February 2000
- DOI:
- 10.1111/j.1749-6632.2000.tb06165.x
- arXiv:
- arXiv:astro-ph/9909288
- Bibcode:
- 2000NYASA.898...90Z
- Keywords:
-
- Free Convection;
- Stellar Convection;
- Stellar Interiors;
- Solar Interior;
- Plumes;
- Helioseismology;
- Entrainment;
- Turbulence;
- Solar Physics;
- Astrophysics
- E-Print:
- Proceedings of the 14th Florida Workshop in Nonlinear Astronomy and Physics, "Astrophysical Turbulence and Convection", Eds. J.R. Buchler and H. Kandrup, to appear in the Annals of the New York Academy of Sciences (15 pages, 3 figures)