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Diverging Eulerian Multiphase

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Old   March 7, 2012, 06:23
Default Diverging Eulerian Multiphase
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siamak rahimi ardkapan
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I am simulating particles in the air.
The geometry is a room and a candle inside.
When I try steady state, it shows from the beginning floating point.
When I use Unsteady with low relaxation factors, it works to some extent, but whenever I change it to steady state, again it starts to diverge.
Any advice is highly appreciated.
Thanks
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Old   March 7, 2012, 18:51
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Looks like an Eulerian multiphase simulation, right?
In that case, run it laminar, it's very unstable when running it turbulent.
Another try is to reduce under-relaxation factors to very very very low numbers.
Or even better: Try both at the same time!

I understand that's not satisfying, but unfortunately the Eulerian approach is very unstable under turbulent conditions. There are too much equations affecting each other.
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Old   March 8, 2012, 02:59
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Thanks abdul099, it is so nice of you
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Old   January 2, 2014, 13:12
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Hi,
Did you get the solution with steady state?
I have the same problem.
can you help me!
thanks in advance
best!
Kanarya
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