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c120613 April 12, 2010 08:21

domains for fan
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Dear all,

I was simulating a fan and 3 components have been included. these components from the inlet to the outlet of the fan compressor are (see the attached file):

- inlet part which is identified as rotor and includes the initial part of the nose from r=0;
- rotor part where is possible to identify the rotor blades of the fan;
- stator where is possible to look the stator blades.

However I'm not sure that this case can work because for only one stage we are using 3 domain instead of two (rotor and stator only).

Somebody knows if my solution is fine or not?

Kind regards


ghorrocks April 12, 2010 18:33

It should work fine. Why do you suspect it does not work?

Attesz April 14, 2010 07:19

why is your inlet part defined as rotor? isn't it a slice of the inlet pipe? it's not wrong using 3domains instead of two.

c120613 April 14, 2010 08:29

The reason why you have the first part as a rotor part is because in that domain at the hub level you have the part of the nose which has to achieve the radius 0. the nose has to have the same rotational speed as the rotor, for mechanical continuity reasons.

Kind regards

Domenico di Cugno

ghorrocks April 14, 2010 18:28

You use rotating frames of reference when the mesh needs to rotate. If the geometry is axially symmetry then you can either choose it to be a rotating frame of reference or a stationary frame of reference. If the wall in the axially symmetric body is not in the frame of reference you can then choose it to be a rotating wall (for a stationary frame of reference) or a counter rotating wall (for a rotating frame of reference).

I think that was a complicated explanation of a simple concept. Hopefully you get the idea.

You should try to minimise the number of GGIs. With the trick mentioned above you should eb able to eliminate one of your GGIs.

But I repeat my comment from my first post. What makes you think what you are doing is wrong? If you use 2 or 3 domains it should still give the same result.

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