Astronomy and Astrophysics – Astrophysics
Scientific paper
2003-02-28
Astronomy and Astrophysics
Astrophysics
12 pages, 7 figures (low resolution), talk given at the 3D Stellar Evolution Workshop, held in Livermore, July 2002, to appear
Scientific paper
We discuss recent advances made in modelling the complex magnetohydrodynamics of the Sun using our anelastic spherical harmonics (ASH) code. We have conducted extensive 3--D simulations of compressible convection in rotating spherical shells with and without magnetic fields, to study the coupling between global-scale convection and rotation in seeking to understand how the solar differential rotation is established and maintained. Such simulations capable of studying fairly turbulent convection have been enabled by massively parallel supercomputers. The resulting convection within domains that capture a good fraction of the bulk of the convection zone is highly time dependent and intricate, and is dominated by intermittent upflows and networks of strong downflows. A high degree of coherent structures involving downflowing plumes can be embedded in otherwise chaotic flow fields. These vortical structures play a significant role in yielding Reynolds stresses that serve to redistribute angular momentum, leading to differential rotation profiles with pole to equator contrasts of about 30% in angular velocity $\Omega$ and some constancy along radial line at mid latitudes, thereby making good contact with deductions from helioseismology. When a magnetic field is introduced, a dynamo regime can be found that does not destroy the strong differential rotation achieved in pure hydrodynamics cases. The magnetic fields are found to concentrate around the downflowing networks and to have significant north-south asymmetry and helicity.
Brun Allan Sacha
Toomre Juri
No associations
LandOfFree
Solar Turbulence and Magnetism Studied Within a Rotating Convective Spherical Shell does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Solar Turbulence and Magnetism Studied Within a Rotating Convective Spherical Shell, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Solar Turbulence and Magnetism Studied Within a Rotating Convective Spherical Shell will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-643388