The outer third of the Sun's radius is convectively
unstable. Very turbulent motions from this zone may penetrate into
stable layers below, mixing temperature, momentum and chemicals
significantly there. In an attempt to understand such processes,
researchers at Colorado University created a simple model of this
situation.
Shown here is a visualization of enstrophy (vorticity squared)
from such a simulation of penetrative turbulent convection in a
compressible ideal gas (PTCC). The physical domain is divided into
two halves, where the upper is unstably stratified and the lower
is stably stratified, enforced by an imposed thermal conductivity
profile. Intense enstrophy structures (bright yellow, opaque) can
be seen in the convection, including strong, coherent, downflowing
plumes, which can penetrate into the lower stable half of the box.
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