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Old   September 4, 2012, 21:58
Question CFX Duct in Atmospheric Pressure
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Leonardo Martinho
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Hi, I started to use the CFX for my work in my university, and I am facing some problems with him.

I will explain my model first. Imagine a duct, with a nozzle of diameter 352 mm in entrance and an outlet diameter of 100 mm, under atmospheric pressure (1 atm) it will have an inlet velocity of 5 m.s-1. In my model I already put the symmetry.

In boundary conditions i put inlet with 5ms-1, outlet of static pressure 0, free slip in walls, openings of 0 entrainment pressure.

Always an error occur, if I put in modelling boolean the operation to substract and no to preserve tool bodies, I get the flow around the duct. If i yes to preserve tool bodies, when I go to solver occur errors like: "The ASNSYS CFX solver exited wit return code 1" in the beggining of the solver.

Attached is my model, meshing and flow. Please, what I am doind wrong? I also tried to use and already opened duct and did not work too.
Attached Images
File Type: jpg Fluid Flow CFX.jpg (35.4 KB, 20 views)
File Type: jpg mesh.jpg (49.5 KB, 21 views)
File Type: png model.png (88.4 KB, 19 views)
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Old   September 5, 2012, 06:09
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Glenn Horrocks
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What are you trying to model? Why are you doing this analysis?
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Old   September 5, 2012, 11:06
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Are you interested in the flow INSIDE the shape on your pictures or AROUND it?
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Old   September 5, 2012, 13:24
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Felipe Gobbi
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Fundamental question Lotus!

Seems like a simple analysis.
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Old   September 5, 2012, 22:33
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It looks like you have no interfaces, so the two volumes would act like 2 separate bodies if they were two different domains, but it looks as if you have them both in the same domain. The inner body has two openings for some reason but they are not connected to anything.

Get rid of the openings. Since these bodies are both the same domain flow will go through your "openings" from your duct

Insert wall interface where there is a wall between the two bodies, or else it would act as if there was nothing inside at all since it would all be a fluid everywhere.

I don't know what you are trying to model, so this is just my best guess.

Last edited by evcelica; September 6, 2012 at 08:50.
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duct, flow

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