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I want to observe karman vortex by pimplefoam

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Old   January 29, 2013, 07:31
Default I want to observe karman vortex by pimplefoam
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Baek, Donghae
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Hi everyone.
first of all, I am sorry that I am not good in english.

I am a newbie in Openfoam and CFD.
I want to observe vortex created by pimplefoam around circular cylinder
and compare with RASmodel and LESmodel
actually I have alreay tried creating the case created by LESmodel and observed vortex successfully.

but result of RASmodel is not good.
there is no vortex in RASmodel and I seems like laminar flow.
I don't know why vortex don't appear in RASmodel.

i think the problem is in k or epsilon.

please somebody help me.
it take for 2week to find what problem is.

my case file is attached.

https://docs.google.com/file/d/0B1jB...FGUnRpS1U/edit
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Last edited by wes1204; January 29, 2013 at 08:51.
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Old   January 29, 2013, 07:42
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inlet velocity is 1m/s.
channel width is 4.5m
channel length is 17.5m
cylinder D=0.5m

k in 0 is 0.000375 by (3/2)*(U*I)^2 (I = 0.005)
epsilron in 0 is 0.0000026 by (Cu^0.75)(k^1.5 / l) (Cu=0.09 , I = 20% of channel width)
nu is 1e-06.

plese help me
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Old   April 9, 2013, 11:54
Default mesh problem.
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Baek, Donghae
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Although this thread is written by me, I reply myself for other foamer who encounter to same problem.

Problem is Mesh.

I remake mesh more finer. Approximatly 2times.

Then vortex appeared.

Other condition is same.
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