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Boundary conditions for potentialFoam

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Old   May 7, 2011, 02:59
Default Boundary conditions for potentialFoam
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How can I specify boundary conditions for potentialFoam in terms of velocity potential? Or how can a dirichlet boundary condition for velocity potential be implemented in potentialfoam?
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Old   May 8, 2011, 04:05
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is in the dirichlet boundary condition the value of velocity fixed or zero at boundary conditions? so use

{
type fixedValue;

value uniform (0 , 0 , 0);
}
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Old   May 8, 2011, 04:33
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I want to specify phi=constant boundary condition. Is there any way to specify boundary condition for phi? As per my understanding, it writes the phi values after convergence. We can only input U and P values.
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Old   May 8, 2011, 09:44
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as i know phi = U & mesh.Sf() so when U is fixed at the boundary phi should be fixed too
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Old   May 8, 2011, 14:26
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Thank you. What does "U & mesh.Sf()" exactly mean mathematically? I am not aware of the syntax used in source code of openfoam. d(phi)/dn = Un, so does U & mesh.Sf() integrate U to get phi?

Also How do I then calculate U so that I get desired value of phi ? Do I have to go for trial and error?
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Old   May 8, 2011, 15:13
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phi = U & mesh.Sf()
U= velocity vector
& = inner product
mesh.Sf() = normal surface vector

i guess you just need to divide ur desired phi into ur boundary area cross section,so you have desired U
then evaluate U in dict!
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Old   May 16, 2011, 22:14
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Basic confusion:

is phi flux or velocity potential?
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Old   May 17, 2011, 04:11
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its flux
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