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-   -   [ICEM] Cartesian for a simple channel, failure~~ (http://www.cfd-online.com/Forums/ansys-meshing/83910-cartesian-simple-channel-failure.html)

lotus_blue January 14, 2011 12:09

Cartesian for a simple channel, failure~~
 
1 Attachment(s)
:D hello

I am meshing a uniform square channel with ICEM.
The Cartesian method applied by the 'Femur' tutorial of ICEM CFD is used. Basically, I defined a Cartesian grid first and generated mesh based on this grid.
It looks straightforward...but I ended up with something like this~~~at the outlet of the channel...Attachment 6059
Anyone has any idea?:eek:

la7low January 14, 2011 20:05

Dud you use blocking method? It looks like an O-grid at the channel end...

PSYMN January 15, 2011 16:22

Don't use BFCart, just use Hexa Blocking...

In this case, it looks like a projection problem.

lotus_blue January 17, 2011 16:16

I managed to get it done in 3 ways:
(1) Blocking->Save Unstruct Mesh; then Mesh-> Load from Blocking.
(2) Pre-Mesh; then Convert to Unstruct Mesh.
(3) Pre-Mesh; then Mesh-> Load from Blocking.

They all seem to generate the same results. In the tutorial, every time a mesh is generated, I need to go to the Mesh Tab, and click "Compute". But in this case, a mesh can be done without going to Mesh Tab~~~Could anyone say something about this?
And what is the mechanism behind the 3 different ways?:confused:

~~~~~~~~~~~~
And Simon, could you tell me what exactly is the "projection problem"?


Thanks for all your replies.:D

PSYMN January 17, 2011 17:32

redundancy...
 
1) The first half creates a UNS file from the loaded and computed blocking file and saves that uns file. The second half extracts an unstructured mesh from the loaded and computed blocking file. I never do it this way... Actually these are two different things... If you did the first half, you don't need the second half, you could just load the uns mesh file.

2) This converts the loaded and computed blocking file into an unstructured mesh file, saves it as hex.uns and loads it into the mesh editor... This is what I usually do.

3) This works too, similar to 2). Consider it a redundancy...


By projection problem, I mean it looks like the mesh in your last picture is not projecting to the end of the box... Is there a surface where it projected to or did it just start there and not project, I can't tell from here. I can only see that there is a problem.

lotus_blue January 18, 2011 15:15

It is a square channel. All the curves are associated with the edges of the blocking. The mesh was supposed to project to the end of the box, but it didn't. Don't know why it didn't work...Any ideas?:D

la7low January 18, 2011 15:30

Project face to surface yourself. Maybe that helps...

lotus_blue January 18, 2011 15:44

Quote:

Originally Posted by la7low (Post 291008)
Project face to surface yourself. Maybe that helps...

:) thanks.:)


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