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October 28, 2009, 05:52 |
pressure unit ? boundary condition
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#1 |
Senior Member
Jiang
Join Date: Oct 2009
Location: Japan
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Dear Foamers,
I am confused about pressure unit. in SI unit ,should use Pascals, that's kg/(m*s2). and so [1 -1 -2 0 0 0 0]. why openfoam use like this in many tutorials: dimensions [0 2 -2 0 0 0 0]; internalField uniform 0; for pressure boundary conditions ,we should use real pressure? for example: 101325 Pa. Thank you. |
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October 28, 2009, 06:43 |
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#2 |
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Maxime Perelli
Join Date: Mar 2009
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OpenFOAM uses the rho-normalized pressure p*=p/rho
[p*] = {kg/(m.s**2)} /(kg/m**3) = m**2/s**2 = [0 2 -2 0 0 0 0] in your BC you just have to divide your real pressure with your density
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October 28, 2009, 08:14 |
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#3 |
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Jiang
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December 29, 2013, 19:21 |
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#4 | |
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Quote:
Any normalization applied to those units Thanks |
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January 2, 2014, 05:43 |
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#5 |
Senior Member
Join Date: Aug 2013
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Hi Ke Wu,
Nope. Rest of the variables are generally not normalized by the density. As far as I know only p and p_rgh. If you want to double check, you can always see dimensions for every variable and check if it is the right unit or not. Regards, Antimony |
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October 21, 2018, 16:36 |
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#6 |
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merve
Join Date: Jul 2018
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Wall Shear Stress is the same in OpenFOAM.
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