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Old   August 16, 2011, 16:27
Default bounding velocity
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Farshad
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Hi,
I want to bound my velocity by the following commands:
volScalarField ux=U.component(0);
volScalarField uy=U.component(1);
volScalarField uz=U.component(2);
ux.max(5);
uy.max(10);
uz.max(0);

but when i monitor min/max of my velocity i see:
(18.58 27.6014 2.57e-15)

please tell me why openfoam does not obey my codes!

Kind Regards,
Farshad
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Old   August 16, 2011, 21:39
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Nima Sam
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forAll (U,celli){
U[celli].x()=max( U[celli].x() ,5);
...
}
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Old   August 17, 2011, 05:48
Default problem remains
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Farshad
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Hi,

Thanks for the code but velocity is still too high at some points inside domain and my problem still remains.

Thanks,

Farshad
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Old   August 17, 2011, 14:46
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dear farshad
where do u add this code in your solver?
maybe U rewrite again! so change the position of code for example put in pEqn.H
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Old   August 27, 2011, 08:54
Default bounding problem
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Farshad
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Dear Nima,

I put the code in many places to see if it works but the maximum velocity is still 18 that shoud be 9m/s .
If i dont extend the bounded region i would have the continuity problem and it does not converge.
The interesting thing is if i solve energy equation coupled with momentum equation i get less continuity problems.(maybe because of huge grad(p) in momentum equation)

Thanks,

Farshad
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Old   August 29, 2011, 17:01
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Nima Sam
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hi dear farshad
its some how sensible! when you bound the velocity!!! you will encounter continuity problem!!! if you want to reduce maximum velocity maybe you need change ur boundary condition, ur initial condition, even ur mesh size and ur mesh type!
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