[ANSYS Meshing] Negative element quality but no negative elements

Shruti · July 2, 2015, 12:32

Hi everyone,

When I checked my pre-mesh quality today, it showed 1 negative value, -0.094, but no negative elements. I am unsure what to make of this, and how should I get rid of negative quality in such a case?
I also checked the quality for unstructured mesh, and I got the same quality histogram.

Kapi · July 2, 2015, 18:54

Hi Shruti,

Find out which part of your geometry has bad quality elements first, then use Sizing or any other way which suits your geometry and create a better mesh around that region.
This should solve your problem.

Cheers
KAPI

Shruti · July 3, 2015, 07:31

Actually, my geometry has about 3-4 sensitive regions which are problem areas. How would you suggest finding out which area has these negative values in such a case? When I had negative elements, I could simply click on them and find out.

Kapi · July 9, 2015, 01:27

Hi Shruti,

Since you know there are 3-4 sensitive areas then tackle those areas and try to get best mesh possible in those area.
Once you have mesh, check if you are still getting negative value.
Even if you were not getting negative value, I would have suggested you to have good mesh around sensitive area, it gives you more accurate result.

Cheers
KAPI

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
[blockMesh] Errors during blockMesh meshing	Madeleine P. Vincent	OpenFOAM Meshing & Mesh Conversion	51	May 30, 2016 10:51
[ICEM] Eliminating Negative Volume Elements	Josh	ANSYS Meshing & Geometry	16	July 9, 2014 13:01
[blockMesh] non-orthogonal faces and incorrect orientation?	nennbs	OpenFOAM Meshing & Mesh Conversion	7	April 17, 2013 05:42
[ICEM] Hex refinement negative quality afterwards	Anorky	ANSYS Meshing & Geometry	8	March 22, 2010 03:25
Negative quality elements in ICEM Grid	Kartik	CFX	2	June 17, 2005 04:45

July 2, 2015, 18:54		#2
Kapi Senior Member Join Date: Apr 2014 Location: Melbourne Posts: 584 Rep Power: 14	Hi Shruti, Find out which part of your geometry has bad quality elements first, then use Sizing or any other way which suits your geometry and create a better mesh around that region. This should solve your problem. Cheers KAPI

July 3, 2015, 07:31		#3
Shruti New Member Join Date: Apr 2015 Posts: 8 Rep Power: 10	Actually, my geometry has about 3-4 sensitive regions which are problem areas. How would you suggest finding out which area has these negative values in such a case? When I had negative elements, I could simply click on them and find out.

July 9, 2015, 01:27		#4
Kapi Senior Member Join Date: Apr 2014 Location: Melbourne Posts: 584 Rep Power: 14	Hi Shruti, Since you know there are 3-4 sensitive areas then tackle those areas and try to get best mesh possible in those area. Once you have mesh, check if you are still getting negative value. Even if you were not getting negative value, I would have suggested you to have good mesh around sensitive area, it gives you more accurate result. Cheers KAPI