[zhangyan]

Originally Posted by davibarreira

The dictionary for makeAxilMesh is rotationDict not rotateDict. Can you post your blockMeshDict here so I can take a look?

oh,thanks!

[zhangyan]

Originally Posted by davibarreira

The dictionary for makeAxilMesh is rotationDict not rotateDict. Can you post your blockMeshDict here so I can take a look?

oh
you mean the command rotateMesh don't need any dictionary?

[davibarreira]

Ok, so I figured out how to use makeAxialMesh properly thanks to this old thread: http://www.cfd-online.com/Forums/ope...mmetric-6.html

Forget what I said before about using the option makeAxialOldMode 1.

Just put the rotationDict and collapseDict in your system folders (you can use the ones attached, they work on your case). After that, run blockMesh to generate your mesh, then makeAxialMesh. Finally, run collapseEdges -latestTime . Your directory will look something like this (the numbers of the folders may change a bit):

0/ 0.0025/ 0.005/ constant/ system/

Copy the polymesh folder inside the 0.005 directory and replace it with your polymesh inside the constant/ folder (remember to back it up, so you dont lose your original blockMeshDict). And that's it.

P.S: rotateMesh is not for creating axial meshes, so you dont need to use it.

[zhangyan]

thanks for your kindness!
I will try it.

[zhangyan]

Originally Posted by davibarreira

Ok, so I figured out how to use makeAxialMesh properly thanks to this old thread: http://www.cfd-online.com/Forums/ope...mmetric-6.html

Forget what I said before about using the option makeAxialOldMode 1.

Just put the rotationDict and collapseDict in your system folders (you can use the ones attached, they work on your case). After that, run blockMesh to generate your mesh, then makeAxialMesh. Finally, run collapseEdges -latestTime . Your directory will look something like this (the numbers of the folders may change a bit):

0/ 0.0025/ 0.005/ constant/ system/

Copy the polymesh folder inside the 0.005 directory and replace it with your polymesh inside the constant/ folder (remember to back it up, so you dont lose your original blockMeshDict). And that's it.

P.S: rotateMesh is not for creating axial meshes, so you dont need to use it.

maybe I can operate in another way:blockMesh...makeAxialMesh -overwrite...collapseEdges -overwrite?

[gschaider]

Originally Posted by zhangyan

maybe I can operate in another way:blockMesh...makeAxialMesh -overwrite...collapseEdges -overwrite?

Try it. (as some time passed you probably did it and it worked)

[dumas]

I have a problem to generate the axisymmetric mesh in my work, someone could help me, I am sending the files, would be grateful if anyone could help.


My openFoam 2.3

Thanks.

[zhangyan]

Originally Posted by dumas

I have a problem to generate the axisymmetric mesh in my work, someone could help me, I am sending the files, would be grateful if anyone could help.


My openFoam 2.3

Thanks.

Hi Santos,
1~~~At first,the makeAxialMesh tools should be compiled correctly.
2~~~In the file "blockMeshDict" , you should add a face named "center" which the mesh can rotate around it. Like this :

center
{
type symmetryPlane;
faces
(
(13 0 14 27)
);
}
3~~~And then,in the dictionary "system",two files "rotationDict" and "collapseDict" are needed. See the #183 floor.
4~~~At last,input these commands in order:
blockMesh
makeAxialMesh -overwrite
collapseEdges -overwrite
checkMesh
5~~~Good luck!
6~~~Forgive my poor English.

[dumas]

Thank zhangyan, I will try to perform these procedures. No problem, sorry my English.

[dumas]

Originally Posted by zhangyan

Hi Santos,
1~~~At first,the makeAxialMesh tools should be compiled correctly.
2~~~In the file "blockMeshDict" , you should add a face named "center" which the mesh can rotate around it. Like this :

center
{
type symmetryPlane;
faces
(
(13 0 14 27)
 
}
3~~~And then,in the dictionary "system",two files "rotationDict" and "collapseDict" are needed. See the #183 floor.
4~~~At last,input these commands in order:
blockMesh
makeAxialMesh -overwrite
collapseEdges -overwrite
checkMesh
5~~~Good luck!
6~~~Forgive my poor English.

hello zhangyan,

I tried to take the steps you suggested, but the mesh was the same as the initial mesh. Execultar got the makeAxialMesh program, was generated the 0005 file, but nothing has changed.

Chosen as the center

(
(0 1 7 6) // Bot (0)
(1 12 14 7) // Bot (2)
);

Would have a question,

frontandback is the type empty?

If you could generate this mesh to me with the axis of symmetry equal to figure Site: https://openfoamwiki.net/index.php/C.../MakeAxialMesh

[ali.ghaemi]

Hi Foamers

I am encountering a strange problem creating axisymmetric meshes using MAM. The mesh looks pretty fine in paraview, before using collapseEdges. But when I use collapeEdges, it converts the axisymmetric mesh to the original 2D mesh.
I also tried using makeAxialMesh -overwrite. Thereafter, OF exits by (Floating point exception) error, when I use collapeEdges or checkMesh.
Does any body use MakeAxialMesh_2.x on OF-2.3.1? From what I have read in this thread, I guess it is a compatibility problem.

Thanks in advance


PS: please find attached the corresponding case.

[davibarreira]

You might want to try OF 2.4, they made some improvements to the makeAxialMesh.

Cheers

[Antony_P]

Hi,

While running makeAxialMesh i am getting this warnig quite often.


--> FOAM Warning :
From function wedgePolyPatch::calcGeometry(PstreamBuffers&)
in file meshes/polyMesh/polyPatches/constraint/wedge/wedgePolyPatch.C at line 72
Wedge patch 'wedge_neg' is not planar.
At local face at (1.5137 0.0402188 -0.000877755) the normal (8.01877e-18 -0.0218097 -0.999762) differs from the average normal (-3.78148e-22 -0.0218097 -0.999762) by 1.72515e-15

is there something i should check or can i ignore this?

Thanks

[schmidt_d]

Looking at the digits of the normal vectors, it appears that this small discrepancy is a consequence of round-off. My guess is that you can safely ignore this warning.

[Antony_P]

Thanks schmidt,

I have yet another problem. I am doing a external flow study on a axis symmetric body.

I am using blockMesh -> snappyHexMesh -> makeAxialMesh -> collapseEdges.

when i view the mesh it is all fine . but when i check the mesh with 'checkMesh' i am getting 7 errors.

I have attached the log file i received for checkMesh.

Is there anything that i have to do with rotationDict or collapseDict?

Checking topology...     Boundary definition OK.     Cell to face addressing OK.     Point usage OK.     Upper triangular ordering OK.     Face vertices OK.     Number of regions: 1 (OK).  Checking patch topology for multiply connected surfaces...                    Patch    Faces   Points                  Surface topology                    inlet      100      202  ok (non-closed singly connected)                   outlet      100      202  ok (non-closed singly connected)                upperWall     1200     2402  ok (non-closed singly connected)             frontAndBack        0        0                        ok (empty)                lowerWall     1532     2677  ok (non-closed singly connected)                      ua1    31770    32535  ok (non-closed singly connected)         frontAndBack_pos   142483   145823  ok (non-closed singly connected)         frontAndBack_neg   142375   145713  ok (non-closed singly connected)  Checking geometry...     Overall domain bounding box (-1.1 0 -0.0141658) (4.6 0.325 0.0141868)     Mesh (non-empty, non-wedge) directions (1 1 0)     Mesh (non-empty) directions (1 1 1)     Wedge frontAndBack_pos with angle 2.49754 degrees  ***Cannot find opposite wedge for wedge frontAndBack_pos     Boundary openness (-9.02861e-19 1.54122e-14 1.31133e-12) OK.  ***Open cells found, max cell openness: 0.0218662, number of open cells 152521   <<Writing 152521 non closed cells to set nonClosedCells   <<Writing 228809 cells with high aspect ratio to set highAspectRatioCells  ***Zero or negative face area detected.  Minimum area: 0   <<Writing 130 zero area faces to set zeroAreaFaces  ***Zero or negative cell volume detected.  Minimum negative volume: -7.9226e-17, Number of negative volume cells: 120358   <<Writing 120358 zero volume cells to set zeroVolumeCells     Mesh non-orthogonality Max: 175.974 average: 70.2632    *Number of severely non-orthogonal (> 70 degrees) faces: 330991.  ***Number of non-orthogonality errors: 306103.   <<Writing 637094 non-orthogonal faces to set nonOrthoFaces  ***Error in face pyramids: 1338 faces are incorrectly oriented.   <<Writing 1338 faces with incorrect orientation to set wrongOrientedFaces  ***Max skewness = 1.58762e+06, 118079 highly skew faces detected which may impair the quality of the results   <<Writing 118079 skew faces to set skewFaces     Coupled point location match (average 0) OK.  Failed 7 mesh checks.  End

[Antony_P]

sorry for the previous post.

the error is

Checking topology...
    Boundary definition OK.
    Cell to face addressing OK.
    Point usage OK.
    Upper triangular ordering OK.
    Face vertices OK.
    Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
                   Patch    Faces   Points                  Surface topology
                   inlet      100      202  ok (non-closed singly connected)
                  outlet      100      202  ok (non-closed singly connected)
               upperWall     1200     2402  ok (non-closed singly connected)
            frontAndBack        0        0                        ok (empty)
               lowerWall     1532     2677  ok (non-closed singly connected)
                     ua1    31770    32535  ok (non-closed singly connected)
        frontAndBack_pos   142483   145823  ok (non-closed singly connected)
        frontAndBack_neg   142375   145713  ok (non-closed singly connected)

Checking geometry...
    Overall domain bounding box (-1.1 0 -0.0141658) (4.6 0.325 0.0141868)
    Mesh (non-empty, non-wedge) directions (1 1 0)
    Mesh (non-empty) directions (1 1 1)
    Wedge frontAndBack_pos with angle 2.49754 degrees
 ***Cannot find opposite wedge for wedge frontAndBack_pos
    Boundary openness (-9.02861e-19 1.54122e-14 1.31133e-12) OK.
 ***Open cells found, max cell openness: 0.0218662, number of open cells 152521
  <<Writing 152521 non closed cells to set nonClosedCells
  <<Writing 228809 cells with high aspect ratio to set highAspectRatioCells
 ***Zero or negative face area detected.  Minimum area: 0
  <<Writing 130 zero area faces to set zeroAreaFaces
 ***Zero or negative cell volume detected.  Minimum negative volume: -7.9226e-17, Number of negative volume cells: 120358
  <<Writing 120358 zero volume cells to set zeroVolumeCells
    Mesh non-orthogonality Max: 175.974 average: 70.2632
   *Number of severely non-orthogonal (> 70 degrees) faces: 330991.
 ***Number of non-orthogonality errors: 306103.
  <<Writing 637094 non-orthogonal faces to set nonOrthoFaces
 ***Error in face pyramids: 1338 faces are incorrectly oriented.
  <<Writing 1338 faces with incorrect orientation to set wrongOrientedFaces
 ***Max skewness = 1.58762e+06, 118079 highly skew faces detected which may impair the quality of the results
  <<Writing 118079 skew faces to set skewFaces
    Coupled point location match (average 0) OK.

Failed 7 mesh checks.

End

[davibarreira]

Try to use extrudeMesh after snappyHexMesh

[Antony_P]

Thanks Davibarreira,

extrudeMesh did not help. But i don't see the use of extrudeMesh. Do i have to make any changes in extrudeMeshDict or in collapseMeshDict??

[Hisham]

Hallo Antony,

Have you defined frontAndBack_neg as wedge in your constant/polyMesh/boundary file?

Best regards
Hisham

[Antony_P]

@Hisham.
After running snappyHexMesh frontAndBack is patch.
After running makeAxialMesh frontAndBack is patch, frontAndBack_pos is wedge and frontAndBack_neg is wedge.