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Mesh Transformation in CFX PRE

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Old   August 20, 2018, 04:12
Default Mesh Transformation in CFX PRE
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Hi

I am trying to do a rotor stator simulation, and in that I am meshing only a section of the rotor (36degree) and then rotating it in CFX PRE. For the ease of sweepable mesh, I did divide the geometry and then used the share topology. And named all the surfaces which are necessary for the naming. BUt in CFX Pre when I rotated the geometry to 360 degree, it created different 2D regions and with also each named selection was 10 times and then there was this Entire_Wall.. bla bla..I used this named selection with Entire.....
But those which were not selected was in the Rotor_default Boundary condition. But those surfaces where already selected as my boundary conditions using the entire. What should I use with this Default Boundaries and it is selected as walls.
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Old   August 20, 2018, 08:51
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An image would help. And please label the image. Make sure you ask a good question as that is the only way you will get a useful answer.
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Old   August 20, 2018, 23:04
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The rotor should have Entire “ inflow region”, Entire “outflow region” and then all the high side and low side symmetry interfaces, then the hub, shroud, and blades, will show up as Default and be a wall. If you named the blades, hub, and shroud region you can add them as wall boundary conditions separately so that post processing goes better.

Still not 100% sure what you’re asking.
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Old   August 22, 2018, 04:59
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Hi
Sorry for not clearly explaining.

So basically for the rotor part, there is 20 blades and I just used a small section of the entire rotor (36°) that means 2 rotor blades. This wedge section you can see in the image. I used shared topology etc in the Ansys DM and splitted the part into several bodies so that I can use sweep mesh method in Ansys meshing. And I did the meshing with Match control to the side faces etc. And now in the CFX Pre I transformed the mesh and used the option Rotation to rotate the mesh for 360 degree. And now what you see in the second image is basically the Default Boundary,which is selected a wall, al though its not. This was generated because of the rotation and those faces which are not connected. To avoid this only I used the Match control during the meshing so that the faces are one to one matched and hence no need of any GGI interfaces between each rotation body. But now it seems it created this walls exactly where my initial 36° had those faces on both sides which was connected during the rotation. Now I want to avoid this situation and have no walls there. or get rid of this walls.
Thanks in advance !!
I hope this time I made it clear.
Attached Images
File Type: jpg wALL.jpg (62.0 KB, 58 views)
File Type: jpg rOTOR.jpg (43.6 KB, 53 views)
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Old   August 22, 2018, 20:31
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Why is there a thin volume at the edge? The end faces are circled:

Blocks.png
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Old   August 23, 2018, 06:52
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This is basically the thickness of the interface. And the geometry is sliced in such a way that I can use sweep mesh on it. So the inner radius edge is the rotor diameter and then I created a volume above it and named the outer radius surface as the interface. I hope this is what you are asking about
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Old   August 23, 2018, 20:09
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Quote:
This is basically the thickness of the interface.
What interface? Interfaces don't have thickness, at least the GGI interfaces used in CFX don't.

That body should be sweepable with a single region. That is with the outer sliver merged with the inner region containing the blade. So I do not understand why you have separated them.
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