[FLASH-USERS] Temperature undershooting problem

[Latif]

Hi
Dear all,
Wishing  a happy new year to you all!
I am doing cosmological simulations (including cosmology, hydro, 
gravity, particles, EOS, multi species, cooling) using FLASH3.2 (3.3 as 
well). I have a  problem  that i get undershoots in temperature for few 
zones.  I have tried some options by using different run time parameters 
for hydro module (like using HLLE solver, Godunov method, some other 
parameters as mentioned in run time parameters list) but they don't 
help.  I normally use splitting method, i tried unsplit method with 
latest FLASH version but it seems  it does not work for me.  I do get 
warnings during refinement like "WARNING after amr_prolong: min. 
unk(EINT_VAR)=53948129.70756026".  I have attached density-temperature 
phase diagram as an example. Has any body experienced same problem? What 
could be the possible cause of temperature undershooting? Any ideas how 
to avoid these undershoots ? Your response will be highly appreciated.
Cheers
Latif

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