Just figures and animations from
recent simulations of convection in a box.
Last modified Tuesday, 26-Jun-2018 10:30:13 CDT
Here is a brief look at the formation of
"dust devils" in idealized thermal convection
between free-slip parallel plates.
(This investigation was inspired by the
research of Dr. Katharine Kanak).
The dimensionless diffusivity is 0.01.
The Rayleigh number is 4096
times the critical Rayleigh number of 240.
The layer is heated only from below.
A model with dimensions 4x4x1 and gridpoints 128x128x32 was
run from t=0 to t=32.
There is no vertical vorticity initially,
and all vertical vorticity arises from the tilting
of baroclinically-generated horizontal vorticity.
In the animations of the experiment where only the bottom is heated,
a strong cyclonic "dust devil" forms near the south boundary at t=24.
The above is a vis5d rendering showing a green cone of low pressure
(isosurface -1.63) yellow temperature (isosurface 6.59) and purple
vertical velocity (isosurface 1.3). There is at least the appearance
of the updraft partially wrapping the low pressure. This is expected
to occur as the vortex reaches the thermodynamic speed limit, and the
core becomes hydrostatically balanced.
