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pressure not uniform although velocity is uniform at the inlet

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Old   January 11, 2011, 05:25
Default pressure not uniform although velocity is uniform at the inlet
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Dear all,

I specify the inlet velocity for a multiphase system ( one liquid and two granular solids) but when I simulate I find that the pressure is not uniform across the cross-section of the inlet. Could anybody say why is it so.

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Old   March 6, 2016, 04:58
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I have the same problem
can anybody help?
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Old   March 6, 2016, 11:07
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If you have a viscous flow, pressure does not have to be uniform and in general is not uniform. If you have a uniform velocity inlet it is unlikely to be uniform.
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Old   March 7, 2016, 04:35
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I want to calculate CP on the airfoil
reference pressure in pressure at infinity
if its changed, CP changed too.
is this correct?
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Old   March 7, 2016, 08:50
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The reference pressure is part of the definition of Cp. Meaning it is defined as soon as you have chosen a particular definition for Cp.

But, the reference pressure is usually the dynamic pressure.
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Old   March 7, 2016, 09:46
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so, if i want to plot cp ,what will be the pressure (pa) in reference values ?
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Old   March 7, 2016, 13:57
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How do you define Cp? The reference pressure is there.

Are you asking what is the definition of Cp?
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Old   March 8, 2016, 01:19
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p-p(inf)/q(inf)
p(inf) is defined in reference pressure and is changed during the solution because of velocity inlet BC.
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