[FLASH-USERS] Asymmetric diffusion in 3T MGD

[Julian Bouffard]

Hello,

New FLASH user here, version 4.8.  I have a simple problem that I adapted from the 2D LaserSlab problem, although it has nothing to do with lasers, simply because it had 3T, MDG, and species implemented.

My setup command was:
./setup -auto LaserSlab -2d +cartesian -nxb=16 -nyb=16 +hdf5typeio species=cham,targ +mtmmmt +uhd3t +mgd mgd_meshgroups=6 -parfile=example.par -objdir testProblem

I shut off the laser, and placed a hot circle of aluminum in the center of the grid ( I set temperature of radiation, ion, and electron all to 1000 K, with the background He at 290 ).  The subsequent diffusion of ion, electron, and radiation energies are asymmetric.  I've attached two screen captures at t=0 and t=7e-12.  Is there a simple explanation for this?

Thanks for any insight!

[cid:image001.png at 01DBF7DE.37995E40][cid:image002.png at 01DBF7DE.37995E40]
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