CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Pre-Processing

Converting SnappyHexMesh-Grids without Polyhedra

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 3, 2015, 07:44
Default Converting SnappyHexMesh-Grids without Polyhedra
  #1
Senior Member
 
BastiL
Join Date: Mar 2009
Posts: 530
Rep Power: 20
bastil is on a distinguished road
Hello all,

I am experimenting to use snappyHexMesh for some other applications. Therefore, I need to export a mesh without polyhedral cells. I tried the following with the motorbike tutorial:
Code:
foamToVTK -ascii
vtkUnstructuredToFoam
foamMeshToFluent
Step 1: convert snappyHexMesh-File to VTK to get rid of polyhedral cells (only application I am aware of that does polyhedral decomposition)
Step 2: Get back to OpenFoam
Step 3: Export for further usage, e.g. to Fluent

Step 3 tells me:
Code:
Writing Header
--> FOAM Warning : 
    From function void fluentFvMesh::writeFluentMesh() const
    in file fluentFvMesh.C at line 257
    foamMeshToFluent: cell shape for cell 1098 only supported by Fluent polyhedral meshes.
    Suppressing any further messages for polyhedral cells.
End
I don't expect this. And after checking the mesh there are really polyhedral cells left. However, some cells where definitely decomposed into Tet/Pyramid as I can see. Si I don't understand what's going on there. Any idea or some other way?

Last edited by bastil; November 3, 2015 at 11:24.
bastil is offline   Reply With Quote

Old   November 4, 2015, 07:09
Default
  #2
Senior Member
 
BastiL
Join Date: Mar 2009
Posts: 530
Rep Power: 20
bastil is on a distinguished road
I ran some checkMesh on it. For the snapped mesh it looks like this:

Code:
Overall number of cells of each type:
    hexahedra:     307005
    prisms:        7281
    wedges:        940
    pyramids:      6
    tet wedges:    1649
    tetrahedra:    58
    polyhedra:     35158
    Breakdown of polyhedra by number of faces:
        faces   number of cells
            4   3964
            5   6536
            6   5490
            7   2994
            8   1309
            9   10590
           10   15
           11   8
           12   2351
           13   2
           15   1621
           17   1
           18   275
           21   2
and after conversation:

Code:
Mesh stats
    points:           439799
    faces:            1848069
    internal faces:   1779521
    cells:            682986
    faces per cell:   5.31137
    boundary patches: 1
    point zones:      0
    face zones:       0
    cell zones:       0
Overall number of cells of each type:
    hexahedra:     307005
    prisms:        3715
    wedges:        940
    pyramids:      272475
    tet wedges:    1649
    tetrahedra:    93636
    polyhedra:     3566
    Breakdown of polyhedra by number of faces:
        faces   number of cells
            5   3566
Seems like a number of polyhedral cells is not decomposed by foamToVTK.
bastil is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Polyhedra and sliding mesh? rockewan FLUENT 5 December 1, 2018 19:07
[Other] plot3DToFoam: converting backstep grids from NASA's website samiam1000 OpenFOAM Meshing & Mesh Conversion 2 January 2, 2015 16:51
[snappyHexMesh] snappyHexMesh: How can be avoided polyhedra idrama OpenFOAM Meshing & Mesh Conversion 5 September 27, 2013 06:35
while reading mesh and converting to polyhedra... emreg ANSYS 1 February 10, 2012 17:18
Converting the domain to polyhedra problem? Skywalker FLUENT 2 September 9, 2011 10:00


All times are GMT -4. The time now is 07:14.