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-   -   [ICEM] Geometry in ICEM CFD (http://www.cfd-online.com/Forums/ansys-meshing/85220-geometry-icem-cfd.html)

DaIN February 20, 2011 07:48

Geometry in ICEM CFD
 
1 Attachment(s)
Hi guys,

I am trying to create a mesh in ICEM 12.0 to be used as input file for KIVA-3V. I am experiencing some problems once KIVA reads in the mesh and I am checking out all the steps I followed to find the mistakes I made.
The mesh is a cylindrical mesh with a central circular region on the bottom surface that will be setup as inflow.
The problem I might have with the geometry is that once I apply "Build Diagnostic Topology" I don't get all the lines in red as may seen in the picture.

Do you guys think that when some parts of the geometry are in blue, it is because something went wrong and everything should be in red??

Thanks a lot,

PSYMN February 21, 2011 08:28

Multiple Edges.
 
Blue is a multiple edge... Along those edges you have 3 or more surfaces meeting. In your case the surface of the smaller inner cylinder meets with the two end surfaces (one inside and one out).

It may be fine if that was your design intent, but you should at least be aware of it. Did you intend to have two volumes separated by that inner cylinder surface?

Simon

DaIN February 21, 2011 09:49

Hi Simon, thank you very much for your quick replay :)

No, actually, the point of having the inner region (cylinder) is only in order to include a Boundary Condition at the bottom and top plane. I just need to have one volume to include the whole domain.
What I am thinking now is that perhaps I don't need that surface anymore and I can work without it. I thought that I needed that inner cylindrical surface to split the initial block by O-grid, but I have just found out the inner block of O-grid does not need to be assigned to any edge, O-grid only requires the outer edges to be assigned, am I right?

Thanks a lot

daniel

PSYMN February 21, 2011 10:23

Right... Ogrid doesn't need any geometry to hang on. It scares me to think how hard it would be to use if I also had to chop up all my geometry... (It would be like other meshers :eek: !)

You can delete that inner cylinder and proceed from there.

DaIN February 21, 2011 10:42

Ok that's brilliant, thank you :)

On the other hand, for the geometry I specified above I would like to use two O-grids, one for the annular region and one for the inner circular region.
As far as I understand, you don't need special treatment at the interface between blocks which conform the O-grid, but what about in such a case that you have two O-grids?
Do you know whether I will need any special consideration at the interface between the first and second O-grid??

Thanks a lot,

daniel

PSYMN February 21, 2011 11:47

Nested Ogrids.
 
It is not problem to nest ogrids (one inside the other or part of another or overlapping) without any special treatment.

DaIN February 21, 2011 11:49

that's great!

Thank you very much :)

daniel

mel021184 January 3, 2012 11:32

examples for kiva 3V or kiva 4.
 
Hi, I'm working with kiva 3V.

I need examples for kiva 3V or kiva 4.
non engine application.
someone who can help me?
someone who has worked with kiva 3v or kiva4?
I'm trying to simulate a spray impacting on a surface.


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