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September 10, 2015, 06:11 
Regarding Laminar/Inviscid Flows

#1 
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If I want to simulate a very low turbulence problem, how should I know if I should select laminar or inviscid model in the fluid solver?
Thanks! 

September 10, 2015, 06:25 

#2  
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Filippo Maria Denaro
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Quote:
Your question seems strange ... if you want to set a laminar model that's only for simulating turbulence in a DNS formulation. On the other hand, if you set inviscid flow you should be aware that you cannot simulate confined turbulence and you cannot perform a DNS. So, explain in details what you want to simulate 

September 10, 2015, 07:10 

#3  
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Quote:
I want to compare RANS results with an analytical model (which does not include any turbulence dissipation). so if i want to have CFD results that can be compared with my analytical model (which does not account for turbulence), how should I set my CFD model? invisicd or laminar? thanks! 

September 10, 2015, 07:25 

#4 
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Filippo Maria Denaro
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Still not clear ...RANS provides a statistically averaged solution, what about the type of your analytical solution? I see you need for sure a viscous model


September 10, 2015, 08:17 

#5  
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Quote:
but i also want to check that when I select a invicid/laminar model in the fluid solver, the solution should equal or almost the same as the invisicid analytical model. making sense here? so my question is: whether i should choose a inviscid or laminar model in the fluid solver to compare to my inviscid analytical model. 

September 10, 2015, 08:30 

#6 
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Filippo Maria Denaro
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honestly, I don't see the sense in making comparison between RANS and an inviscid model.... But without more details I can't say much more...
I suppose you should compare an Euler simulation and your inviscid analytical solution 

September 10, 2015, 08:47 

#7  
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Quote:
forget about the RANS part. I am trying to comparing between inviscid model to that from a fluid solver. so the question is what flow physics should I specify for the fluid solver: invisicid or laminar? 

September 10, 2015, 08:58 

#8 
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Filippo Maria Denaro
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The Euler inviscid model


September 12, 2015, 00:46 

#9  
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Quote:
Correct me if I'm wrong. 

September 12, 2015, 16:42 

#10  
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Quote:
for my case, since I am trying to validate results between a inviscid analytical model to that from a fluid codesolver, i should be using prescribing a fluid with very low viscosity or in this case, the inviscid NS equations. thanks. 

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