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Old   March 17, 2010, 18:51
Question Negative Pressure?
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Michael Petrarca
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I have a post open in the meshing/geometry section of the boards. I've finished everything, ran a steady state simulation at 60 mph, k-e turbulence, etc. When I looked at the pressure contour on the surface of the model, at first I thought everything was fine, until I noticed that the legend showed some parts with a negative pressure.

Is this an error that I can fix without too much of a headache? I realized that I need to add inflation layers to my mesh, but without those would a negative pressure occur?

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Old   March 18, 2010, 07:55
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Glenn Horrocks
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The pressure is relative to your reference pressure. Assuming your reference pressure is 1 bar then you have pressure ranging from approx 99500Pa to 100500Pa absolute.
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Old   March 18, 2010, 15:49
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Michael Petrarca
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Quote:
Originally Posted by ghorrocks View Post
The pressure is relative to your reference pressure. Assuming your reference pressure is 1 bar then you have pressure ranging from approx 99500Pa to 100500Pa absolute.

Thank you for your reply. I thought that this was a representation of absolute pressure. Lesson learned .
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Old   March 18, 2010, 17:47
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The absolute pressure is also available as a different variable.
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Old   August 11, 2011, 23:28
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the absolute static pressure of your results will be positive.
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