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big problem about "there is no reference pressure available" massege

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Old   August 25, 2012, 05:27
Default big problem about "there is no reference pressure available" massege
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Fariborz Mohammadi
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hi,
dear friends,
please help me give me a guide about the warning.
thanks,
how can I fix the warning?
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Old   August 27, 2012, 14:14
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The reference pressure warning means that there is no known pressure defined for all times during the simulation. This is problematic because the solver computes pressure differences, not absolute pressure, which means that the pressure differences may be correct but the absolute pressure may drift. Providing a location where the pressure is known for all times (the reference pressure; usually a pressure BC) gives the solver a location and a value to which it can anchor the pressure differences.

Allowing the pressures to drift is usually only a problem when something depends on the absolute pressure, like an equation of state or a force calculation on a partially modeled object.
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Old   March 24, 2013, 14:04
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Try to specify the reference pressure in the initialization tab in flow 3d (the tab indicates a symbol t=0 in the Geometry & Meshing tab)

For eg: Atmospheric pressure in many cases.
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