[Previous] | [Session 5] | [Next]
N.E. Hurlburt (Lockheed Martin Solar and Astrophysics Laboratory), N.O. Weiss (University of Cambridge)
In the bulk of the solar convection zone we expect convection to be efficient and therefore maintain an adiabatic temperature gradient. In most numerical simulations of solar convection the total energy flux within this region is due to the conduction down this gradient (which is small) and the various contributions due to the convective motions. What has often been neglected is the contribution that is transported by radiation.
The contribution of this flux decreases across the layer and thereby deposits a significant amount of thermal energy in the midst of the convection zone. This is in contrast to most simulations of the convection where the input of energy is supplied exclusively by conduction from the boundaries. Mixing length models predict that approximately half of the total energy input to the solar convection zone is deposited, more-or-less uniformly over the convection zone, with the remaining half being conducted from the lower boundary. Thus the study of the behavior of internally-heated compressible convection is warranted.
Previous studies of internally heated compressible convection have been inconclusive due to the shearing instabilities that arise in simple, periodic domains. Here we suppress these instabilities by considering flows in axisymmetric geometries. We conduct surveys of the structure and dynamics of the resulting flows and present possible applications to observed solar and stellar phenomena.
The author(s) of this abstract have provided an email address for comments about the abstract: hurlburt@lmsal.com