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initialize pressure gradient

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Old   June 30, 2011, 07:55
Default initialize pressure gradient
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Jie
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Dear Foamers

I am try to setup a Gaussian vortex case, which has a given velocity field and pressure gradient field. I am able to write a app to initialize the velocity across the flow domain by looping through each individual cells. However, I am having problem to initialize the pressure gradient as it requires more than one cell. Would anyone have some suggestions on how to implement this?

Thank you.
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Old   June 30, 2011, 09:25
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Nima Sam
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my suggestion :
1) add to createFields.H
volVectorField dpdx
(
IOobject
(
"dpdx",
runTime.timeName(),
mesh,
IOobject::MUST_READ,
IOobject::AUTO_WRITE
),
mesh
);

2) add file dpdx with dimension of (p/length) in folder 0

3) use funkySetFields from openFoam wiki to initialize the field
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Old   June 30, 2011, 09:36
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Hi nimasam

It requires more cell points to calculate the pressure gradient but not sure how to convert pressure gradient to pressure?

I came across the funkyFields but never used it before. Would you be able to elaborate a bit more on it?

Thanks for the reply.
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Old   June 30, 2011, 09:46
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i can't understand, whats ur mean ?
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Old   June 30, 2011, 09:49
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Quote:
Originally Posted by nimasam View Post
i can't understand, whats ur mean ?
Sorry for the confusion. What I mean is you need more than one cell to calculate the pressure gradient. Is it possible to calculate the pressure at each cell if I know the pressure gradient? This is because I need to initialize the pressure field but I only have the information of the pressure gradient.
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Old   June 30, 2011, 09:59
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im not sure! it would be compilicated but maybe you can look at streamFunction and use similar method!
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