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hyperleo September 4, 2012 21:58

CFX Duct in Atmospheric Pressure
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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.

ghorrocks September 5, 2012 06:09

What are you trying to model? Why are you doing this analysis?

flotus1 September 5, 2012 11:06

Are you interested in the flow INSIDE the shape on your pictures or AROUND it?

Felggv September 5, 2012 13:24

Fundamental question Lotus!

Seems like a simple analysis.

evcelica September 5, 2012 22:33

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.

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