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[GAMBIT] Elbow with internal formations

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Old   January 26, 2012, 17:07
Default Elbow with internal formations
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Hello,

I am trying to simulate water flow in an elbow with internal formations. In the corner of the elbow is attached a rod which is supported by 3 fins. I created the geometry with gambit 2.4.6. There are three main volumes, the two straight pipes (one empty inside and one with the internal formations) and the corner. I wanted to put Boundary Layer on the fin section so I started meshing from there and was ok. The problem is that the corner-volume (with the rod inside) can't be meshed using hex or hex wedge. The only way I could mesh it was using Hex core mesh with tet/hybrid elements ,which leads to a poor quality mesh and I can't use a boundary layer. Is there any way to mesh it with 'better' elements and BL? Maybe dividing the volumes somehow? Any suggestion would be helpfull.

Thank you in advance
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Old   January 27, 2012, 06:00
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Your BL (in white) is not proper defined.
You don't need to attach a BL on internal surfaces, but on outer surfaces (wall)
So in your case pipe-walls, on rod-walls
Regarding tet-hexcore, you can surely fix your poor element.
You can also spit your domain into 3:
-the lower pipe without rod >> meshed with hexa
-the upper pipe with rod >> meshed with hexa
-the elbow part >> with tet-hexcore
This should be quick meshed.
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Old   January 27, 2012, 18:37
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Hello and thank you for your reply. I probably did not make clear that I am interested in checking the effect of the fins and the rod in the flow so in order to have these results I need a boundary layer on the fins which basically are faces without volume and are solved as shadow-walls in fluent. Also the domain is split in three volumes, as I said in my original post, but because of the geometry of the corner it's not possible to use tet/hex and cooper. If the rod was not united to the corner the cooper would work (I tried it). I would like some ideas about making a HEX mesh in the corner volume and also to be able to have BL in the fins-rod-pipe walls. A mesh with Hexcore and tet/hybrid without BL is what I have now.

Thank you again and I apologize for the length of my answer.
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Old   January 30, 2012, 02:05
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ok then forget my BL point, but the other is still available.
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Originally Posted by vas84 View Post
Also the domain is split in three volumes, as I said in my original post, but because of the geometry of the corner it's not possible to use tet/hex and cooper.
Thank you again and I apologize for the length of my answer.
I would be surprised if you really have no chance to mesh your corner volume with tet-hexcore.
Could you please post a picture of the place where you cannot mesh it with tet-hexcore
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