Unstructured meshes along the border of refineMesh.

Katt · September 1, 2017, 08:03

Hi,

I came across the refineMesh utility of Openfoam to refine specific portions of the domain.

I can partially get what I want (i.e. I can refine the region where I want to refine) but along the border of finer and coarser meshes, I see unstructured meshes which I preferably do not want. [Attached Figure].

Reason being, I need to run few additional nonOrthogonalCorrectors just for these few unstructured cells.

Any idea on how to get over this issue,
K

sati · September 1, 2017, 11:13

Hi,
Those cells aren't really like that, it is only the way paraview displays them.
You can see how your mesh really is by ticking the "use VTKPolyhedron" option in paraview.

Katt · September 1, 2017, 12:10

Thanks,

I am using Paraview version-5.x and can you guide where can i find that option?

I came across the following page:
https://openfoamwiki.net/index.php/FAQ/Postprocessing

Neither of the two mentioned steps in the web-page, worked for me.

That is,
1. Extract cells by region: for my 2D case when I apply this filter along the 3rd dimension, I see nothing. Is this filter applicable for 3D cases only?

2. Use VTK Polyhedron: I cannot find this option. I tried in paraviews search engine as well but hasn't shown anything.

sati · September 4, 2017, 03:42

The option is called "VTK Polyhedra" in paraview 5.4.0 and "use VTKPolyhedron" in paraview 5.0.1

It both versions, it is next to the "Update GUI" of the case properties.

Tobi · September 13, 2017, 05:30

Just as an hint. If one used the paraview command and not paraFoam it is named decompose polyhedra. Actually, the line does not exist but the cell (including this line) is not a hexaeder anymore -> it become a polyhedra (FVM).

September 1, 2017, 11:13		#2
sati New Member Join Date: Mar 2015 Posts: 16 Rep Power: 11	Hi, Those cells aren't really like that, it is only the way paraview displays them. You can see how your mesh really is by ticking the "use VTKPolyhedron" option in paraview. guin likes this.

September 13, 2017, 05:30		#5
Tobi Super Moderator Tobias Holzmann Join Date: Oct 2010 Location: Tussenhausen Posts: 2,708 Blog Entries: 6 Rep Power: 51	Just as an hint. If one used the paraview command and not paraFoam it is named decompose polyhedra. Actually, the line does not exist but the cell (including this line) is not a hexaeder anymore -> it become a polyhedra (FVM). oumnion, Teosim and jandierickx1 like this. __________________ Keep foaming, Tobias Holzmann

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September 1, 2017, 12:10		#3
Katt Member Katt Join Date: May 2017 Posts: 30 Rep Power: 8	Thanks, I am using Paraview version-5.x and can you guide where can i find that option? I came across the following page: https://openfoamwiki.net/index.php/FAQ/Postprocessing Neither of the two mentioned steps in the web-page, worked for me. That is, 1. Extract cells by region: for my 2D case when I apply this filter along the 3rd dimension, I see nothing. Is this filter applicable for 3D cases only? 2. Use VTK Polyhedron: I cannot find this option. I tried in paraviews search engine as well but hasn't shown anything.

September 4, 2017, 03:42		#4
sati New Member Join Date: Mar 2015 Posts: 16 Rep Power: 11	The option is called "VTK Polyhedra" in paraview 5.4.0 and "use VTKPolyhedron" in paraview 5.0.1 It both versions, it is next to the "Update GUI" of the case properties.