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Why is the pressure larger than the total pressure

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Old   November 9, 2012, 03:41
Default Why is the pressure larger than the total pressure
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I am simulating a gas flow through a rotating multi-channels with CFX, both the inlet and outlet are the Opening boundary condition. While the inlet has a reletive pressure of 4atm, and the outlet of 2atm, rotation speed is 10000r/min. When I look the result of my computation, at the inlet plane, the pressure is larger than the total pressure, how could this happened?
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Old   November 9, 2012, 04:30
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Can you show some images of what you are seeing?
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Old   November 9, 2012, 05:07
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[IMG]
These are the inlets, the range of the contour is local, from the picture we can see that the pressure is larger than the total pressure in the inlets plane, I don't know why.

Last edited by greatwall; November 9, 2012 at 05:12. Reason: the pictures didnot show well
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Old   November 9, 2012, 05:09
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Sorry, I do not download files from other websites. Please post them as attachments to this post (using "Go Advanced").
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Old   November 9, 2012, 05:12
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[IMG]http://b323.photo.store.qq.com/psb?/V13rxVKa3rhjqK/dwmy9NgB8guQ2FZrPtVmGUFOOzoOhbMyE*ps3QsggBA!/b/dGl*isCnAAAA&bo=hAOAAQAAAAADACM![/IMG]
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Old   November 9, 2012, 05:24
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1.jpg

2.jpg
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Old   November 9, 2012, 05:36
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We will need to see a bit more of the geometry to make any sense of it. Can you post an image which shows what the flow is actually doing?

Also, is this boundary on a rotating frame of reference? Multiphase? Does it have reverse flow?
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Old   November 9, 2012, 05:51
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This boundary is on a rotating frame of reference, no multiphase. The geometry is a turbine blade internal cooling channel, in the computation, the trailing edges did have reverse flow.
3.jpg
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Old   November 9, 2012, 15:22
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Where is the axis of rotation for the domain?
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Old   November 9, 2012, 20:36
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The axis of the rotation is on the negative y direction
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Old   November 11, 2012, 05:10
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I see. I cannot explain what you are seeing.

What does the total pressure in the stationary frame of reference look like?
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Old   November 12, 2012, 20:49
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The problem has been solved. Thank you! When I put the total pressure in the stationary frame of reference, the result is correct.
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