Effects of a subadiabatic layer on convection and dynamos in spherical wedge simulations. (arXiv:1803.05898v2 [astro-ph.SR] UPDATED)
<a href="http://arxiv.org/find/astro-ph/1/au:+Kapyla_P/0/1/0/all/0/1">Petri J. Käpylä</a> (1,2,3,4,5), <a href="http://arxiv.org/find/astro-ph/1/au:+Viviani_M/0/1/0/all/0/1">Mariangela Viviani</a> (4), <a href="http://arxiv.org/find/astro-ph/1/au:+Kapyla_M/0/1/0/all/0/1">Maarit J. Käpylä</a> (4,3), <a href="http://arxiv.org/find/astro-ph/1/au:+Brandenburg_A/0/1/0/all/0/1">Axel Brandenburg</a> (5,6,7,8), <a href="http://arxiv.org/find/astro-ph/1/au:+Spada_F/0/1/0/all/0/1">Federico Spada</a> (4) ((1) Göttingen University, (2) AIP, (3) ReSoLVE Center of Excellence, Aalto, (4) Max-Planck-Institut für Sonnensystemforschung, (5) NORDITA, (6) Stockholm University, (7) JILA, (8) LASP)
We consider the effect of a subadiabatic layer at the base of the convection
zone on convection itself and the associated large-scale dynamos in spherical
wedge geometry. We use a heat conduction prescription based on the Kramers
opacity law which allows the depth of the convection zone to dynamically adapt
to changes in the physical characteristics such as rotation rate and magnetic
fields. We find that the convective heat transport is strongly concentrated
toward the equatorial and polar regions in the cases without a substantial
radiative layer below the convection zone. The presence of a stable layer below
the convection zone significantly reduces the anisotropy of radial enthalpy
transport. Furthermore, the dynamo solutions are sensitive to subtle changes in
the convection zone structure. We find that the kinetic helicity changes sign
in the deeper parts of the convection zone at high latitudes in all runs. This
region expands progressively toward the equator in runs with a thicker stably
stratified layer.
We consider the effect of a subadiabatic layer at the base of the convection
zone on convection itself and the associated large-scale dynamos in spherical
wedge geometry. We use a heat conduction prescription based on the Kramers
opacity law which allows the depth of the convection zone to dynamically adapt
to changes in the physical characteristics such as rotation rate and magnetic
fields. We find that the convective heat transport is strongly concentrated
toward the equatorial and polar regions in the cases without a substantial
radiative layer below the convection zone. The presence of a stable layer below
the convection zone significantly reduces the anisotropy of radial enthalpy
transport. Furthermore, the dynamo solutions are sensitive to subtle changes in
the convection zone structure. We find that the kinetic helicity changes sign
in the deeper parts of the convection zone at high latitudes in all runs. This
region expands progressively toward the equator in runs with a thicker stably
stratified layer.
http://arxiv.org/icons/sfx.gif
