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Old   March 8, 2005, 13:52
Default Hi all, I am trying to use a
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Hi all,
I am trying to use a dynamic model for LES, but since the first iteration I got "nan" in all solvers...
Has anyone succeeded in using dyn models?
Do I need to do anything else, other than switch the name of the model in turbulenceProperties?
(I started with the "static" model, in my case 1Eq, and than after several timesteps, switched to dyn model)
Thanks,
Luiz
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Old   March 8, 2005, 13:56
Default Do you have a zero turbulence
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Do you have a zero turbulence initial condition? That would do it - have a look at the files in zero directory and make sure they make sense.

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Old   March 8, 2005, 13:59
Default Which dynamic model are you tr
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Which dynamic model are you trying? I have just tried dynSmagorinsky on the tutorial case and it ran fine.

There may be an issue with the dynamic models starting from a zero or even uniform U field. Try running with a non-dynamic model first and then restart with a dynamic model.
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Old   March 8, 2005, 14:03
Default I dont think you can yet switc
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Eugene de Villiers
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I dont think you can yet switch turbulence models in mid-calculation.
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Old   March 8, 2005, 14:04
Default You can restart with a differe
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You can restart with a different turbulence model, I do it frequently.
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Old   March 8, 2005, 14:07
Default Hi Henry, It ran fine with dy
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Hi Henry,
It ran fine with dynSmagorinski, but it blows with dynOneEq...
I did run first with a static (non-dyn) model.
Thanks a lot
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Old   March 8, 2005, 14:10
Default OK, I see what is going on. T
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OK, I see what is going on. The problem is the dynamic models do ynot currently have stabilisation in the terms average(LL && MM)/average(MM && MM) where MM may be locally (or even globally) zero. I will look at the dynOneEq... and tell you what you need to change.
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Old   March 8, 2005, 14:51
Default Try this http://www.cfd-on
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Try this

locDynOneEqEddy.C
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Old   March 8, 2005, 16:41
Default Hi Henry, I tried but it did
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Hi Henry,
I tried but it did not worked.
Did it work for you?
Thanks.
Luiz
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Old   March 8, 2005, 16:44
Default Hi Henry, I tried but it did
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Hi Henry,
I tried but it did not work.
Did it work for you?
Thanks.
Luiz
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Old   March 8, 2005, 16:44
Default Yes, it worked fine for me. P
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Yes, it worked fine for me. Put some print statements in it to check you are calling the new functions, the ones with the limiters in are at the top of the file.
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