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-   -   GmshToFoam undefined faces (http://www.cfd-online.com/Forums/openfoam-meshing-open/61896-gmshtofoam-undefined-faces.html)

derath May 8, 2006 02:05

Hi to all my name is Giusepp
 
Hi to all
my name is Giuseppe and I'm new user of OF and gmsh.
I've a problem with my simple case a cube, so when I use gmshToFoam utility it report this warning:

Exec : gmshToFoam
/home/giuseppe/OpenFOAM/giuseppe-1.3/run/tutorials/simpleFoam prova cubef.msh
Date : May 08 2006
Time : 08:00:30
Host : linux
PID : 7819
Root : /home/giuseppe/OpenFOAM/giuseppe-1.3/run/tutorials/simpleFoam
Case : prova
Nprocs : 1
Create time

Read nVerts:865

Read nElems:4928

Mapping region 6 to Foam patch 0
Mapping region 15 to Foam patch 1
Mapping region 19 to Foam patch 2
Mapping region 23 to Foam patch 3
Mapping region 27 to Foam patch 4
Mapping region 28 to Foam patch 5
Mapping region 1 to Foam cellZone 0
Cells:
total:4016
hex :0
prism:0
pyr :0
tet :4016

Patches:
Patch Size
0 228
1 94
2 94
3 94
4 86
5 228

CellZones:
Zone Size
0 4016

--> FOAM Warning :
From function polyMesh::polyMesh(... construct from shapes...)
in file meshes/polyMesh/polyMeshFromShapeMesh.C at line 573
Found 824 undefined faces in mesh; adding to default patch.
Finding faces of patch 0
Finding faces of patch 1
Finding faces of patch 2
Finding faces of patch 3
Finding faces of patch 4
Finding faces of patch 5

FaceZones:
Zone Size

Writing zone 0 to cellZone cellZone_0 and cellSet
End

where is my error?
someone can help me?
Thanks to all.
Giuseppe

mattijs May 15, 2006 04:39

It means you do not have defin
 
It means you do not have defined gmsh surfaces on all boundary faces. You obviously have some:

Patch Size
0 228
1 94
2 94
3 94
4 86
5 228

but there are still 824 boundary faces that are not covered by gmsh surfaces.

derath May 19, 2006 06:35

Hi Mattijs exactly which is t
 
Hi Mattijs
exactly which is the right procedure?
This is my simple geo file:
Point(1) = {0,0,0,0.1};
Point(2) = {0.5,0,0,0.1};
Point(3) = {0.0,0.5,0,0.1};
Point(4) = {0.5,0.5,0,0.1};
Line(1) = {1,2};
Line(2) = {2,4};
Line(3) = {4,3};
Line(4) = {3,1};
Line Loop(5) = {2,3,4,1};
Plane Surface(6) = {5};
Extrude {0,0,0.5} {
Surface{6};
}
Physical Surface(101) = {15,6,23,28,19,27};
Physical Volume(100)= {1};
I've seen that 824 faces is the number of prism which gmsh produce, beside tetrahedra is right?
Thanks in advantage
Giuseppe

derath May 19, 2006 12:58

Sorry not prism but triangles.
 
Sorry not prism but triangles....

newbee May 19, 2006 13:38

Hi, maybe its a bug and can be
 
Hi, maybe its a bug and can be solved by running the newest gmsh version (v1.65) at: http://geuz.org/gmsh/src/
If you are to use the mesh you might want to use the extra recombine posibillity in the extruded direction. see the totorial 3 for this.

hsieh May 20, 2006 07:53

Hi, Giuseppe, I ran your si
 
Hi, Giuseppe,

I ran your simple geo file. I got 336 triangles and the rests are Tets. I used gmsh 1.65. Your geo file looked fine to me.

Recombine Surface will give you hex and/or prism elements, which are better than tet elements.

Pei

derath May 21, 2006 01:47

Hi,Pei I've put Recombine Sur
 
Hi,Pei
I've put Recombine Surface im my geo file but i've 96 Triangles 120 Quads 0 Tet 0 Hex and 0 prism
..............
Plane Surface(6) = {5};
Extrude {0,0,0.5} {
Surface{6};
}

Recombine Surface{15,6,23,28,19,27};
..............................

moreover when I use gmshToFoam for import mesh I've FOAM FATAL ERROR : faces deallocated
Where is my mistake?
Thanks Giuseppe

mattijs May 22, 2006 04:54

I don't know much about gmsh b
 
I don't know much about gmsh but an error like

FOAM FATAL ERROR : faces deallocated

probably means that there are no volume elements (tets, hexes etc.) in the file you are trying to read. Just look at the file with an editor. 2nd number is the element type acc. to the gmsh documentation.


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