Convection and stellar structure.
Abstract
The 'theory' of convection used to model stellar convective zones neglects the flux of turbulent kinetic energy and is therefore only applicable to zones that are small compared to a scale height, yet the resulting models have convective zones that are several scale heights thick. In this paper we attempt to quantify the error involved by retaining the kinetic energy flux and assuming that the viscous dissipation is small. This 'theory' leads to a new criterion to determine the extent of convective zones which requires the convection to penetrate into the surrounding stable layers. This new criterion is used in constructing models of main sequence stars, the convective cores in these stars are found to have 50-70% more mass than the old models and slightly lower luminosities so extending the main sequence phase of stellar evolution by up to 70% over previous estimates.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- April 1978
- Bibcode:
- 1978A&A....65..281R
- Keywords:
-
- Convective Flow;
- Stellar Models;
- Stellar Structure;
- Energy Dissipation;
- Error Analysis;
- Kinetic Energy;
- Main Sequence Stars;
- Stellar Evolution;
- Stellar Luminosity;
- Turbulent Mixing;
- Astrophysics;
- Convection:Stellar Structure