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circular cylinder drag crisis, simpleFoam k-w SST model no expected results

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Old   March 20, 2019, 07:23
Default circular cylinder drag crisis, simpleFoam k-w SST model no expected results
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fur
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Francisco Urbano
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Hi,


I'm trying to reproduce the drag crisis for a circular cylinder 2D with simpleFoam. First I tried using spallartAllmaras model for turbulence but values didn't seem to work properly (later I read it is thought to study aerodinamic foils) so I changed to kOmegaSST.

I want to study my mesh sensitiveness with a laminar case before going deep into the transition to turbulent. I'm searching the solution for Reynolds number 1e5 (aproximately the last value before the crisis) so I set the velocity in 0.735 m/s.

However, when calculating the drag coefficient with libforces.so, it oscillates around 0.89 (average calculated value) when expected value is around 1.2 (as shown by Wieselsberger, 1921).
wieselsberger.PNG
cd_steady_oscillation.png

I don't really know what's wrong with my case:
could it be the solvers?
could it be the boundary conditions?
is there anything I'm not taking in account?

One more thing, and I know this is quite subjective, when openning the case in paraview, movement of the body wake looks too fast for me.

Thanks for the help.
Regards.
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Old   August 4, 2019, 09:30
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damu.cfdonline
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Hi, am working on a similar case. Why don't you try pisoFoam?
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