CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   ANSYS Meshing & Geometry (http://www.cfd-online.com/Forums/ansys-meshing/)
-   -   [ICEM] Check Mesh can't work ! (http://www.cfd-online.com/Forums/ansys-meshing/75276-check-mesh-cant-work.html)

peter.wang April 21, 2010 04:59

Check Mesh can't work !
 
1 Attachment(s)
I have been diagnosing some tetrahedral mesh with ICEM > Edit Mesh > Check Mesh. But I found some terms couldn't work, involving Delaunay-violation, Overlapping elements.
I have presented more detail about my problem in the attachments, including four mesh data file. Please give me a hand, I'm waiting online.

peter.wang April 23, 2010 00:03

Why not hand? I'm waiting online! :)

peter.wang April 23, 2010 00:04

Please help me!

PSYMN June 8, 2010 19:52

Still need help?
 
I missed this one, and now you have probably moved on. However, if you still need help with this, let me know.

Simon

peter.wang June 10, 2010 02:31

Thanks for your kindness
 
Quote:

Originally Posted by PSYMN (Post 262182)
I missed this one, and now you have probably moved on. However, if you still need help with this, let me know.

Simon

Absolutely need! Can you offer some suggestion? Free contact with me via Email sanshi.wang@gmail.com.

PSYMN June 10, 2010 13:09

Checks for Surface mesh...
 
Ok, I just took a quick of your attachment and see that this is just about quality metrics. I am curious about why you were doing this research...

I checked (on my own and fired off an email to development and doc) and see that the doc is correct. Your examples are not. Both of these checks are looking for surface elements (triangles), you have provided volume elements (Tetrahedrals).

So Overlapping elements is not usable because it only works on surface elements (TRI_3 and QUAD_4). It checks for all surface element edges if the any angle of the vector between the centroid of the surface element and the mid point of the element edge projected into the surface element plane and the vector between the centroid of a surface neighbor element and the mid point of the element edge projected into the surface neighbor element plane is less than 5 degrees. If so this will be marked as an overlap. These can cause a problem for delaunay because it is difficult to fit a decent tetra between the overlapping tris.

The Delaunay check is similar. it is meant to be run before delaunay, so it applies to tri elements only (which it says in the first few words of the doc.)

Just a side note; Most Delaunay meshers are now much more robust and failing the delaunay check is no longer a concern. I usually just skip it and focus more on the critical issues of single edges and overlapping elements....


All times are GMT -4. The time now is 09:37.