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Old   June 25, 2010, 04:29
Default Setting up a porous media
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Nicholas
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Hi all,

I've been having some trouble setting up a porous media flow in Star-CD v4 through a porous baffle. I know the force ({F_p}) and hence the pressure drop across the baffle and I need to calculate {\alpha} and {\beta}:

{\Delta p = - \rho ( \alpha \upsilon + \beta ) \upsilon}

where {\upsilon} is superficial velocity and {\rho} is fluid density (I assume).

I seem to have too many unknowns, since I do not know the superficial velocity... any ideas would be greatly appreciated.
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Old   June 25, 2010, 08:15
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Oliver Lauer
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But you know pressure drop for a given mass flow. And you now the area of your porous baffle, and the density. So you can calculate a mean velocity. Better would be to have pressure drops for more than one mass flow because you have two unknowns
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Old   June 25, 2010, 10:32
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Pauli
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You have one equation with two unknowns. You need the force/pressure drop at two or more flow rates. Then you can curve fit the equation to the data.
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Old   June 25, 2010, 10:42
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I have one force value, but I don't have an associated flow rate for that force. How can I calculate the flow rate in the porous media?
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