I have two volumes that are nor getting meshed. Cubit exports the following errors listed below and the mesh appears to be distorted and mixing elements of both volumes (see screenshot). The text file with the history to get to the point where the errors are produced is attached.
ERROR: (-9008441): Cannot insert required edge (14518, 54129)
ERROR: (-9008423): Cannot insert required triangle (13969, 1804, 1805)
The errors are printed for several edges and triangles.
test_mesh.txt (157.6 KB)
Hi,
i did run your journal file. I just uncommented a few lines which throws some input errors and the imprint before assignment of the meshing parameters.
forum.jou (157.3 KB)
On my side this meshes without errors. Altough the quality of the tets gets really bad in the sharp tangency.
You could also try to first mesh the surfaces at z = 0 with mesh surface with z_coord=0 before meshing the volumes.
Have you tried to mesh with bigger mesh sizes? Which version of cubit are you running?
I was able to run it with your journal file, meshing the surfaces first did it. I also meshed it with bigger mesh sizes. I am running Cubit 2023.8.0 (see additional features of the version in the screenshot).
Do you have recommendations for improving the quality of the tets in the sharp tangency? thank you
i don’t know how important the sharp tangency is, but an easy way would be to make a webcut near the edge.
forum.jou (157.6 KB)
I tried running your journal file but it crashes during the volume meshing
As in, Cubit crashes
i’ve run the journal file on 3 different coreform cubit versions without failures. it seems that this is probably an issue with the sandia version of cubit
Do you have recommendations for dealing with that challenge? Or alternative ways to improve the quality of the tets in the sharp tangency that won’t cause the Sandia version to crash?
Hi, i am sorry to say, but we don’t support sandia cubit. So i can’t recommend alternatives that will not crash.
One thing that should always work is moving the nodes manually. You could put the nodes you want to move in nodesets and then run a short python loop over them to get them to your desired location.
node_ids=cubit.get_nodeset_nodes_inclusive(1)
cubit.cmd("set node constraint off")
for id in node_ids:
cubit.cmd(f"node {id} move x 100 y 0 z 0")
Can you help me code that for the nodes that you moved when cutting the hard edge in the journal file you shared?
I am sorry to say but we don’t support sandia cubit.
It’s best you ask them for support.
Support email: cubit-help@sandia.gov
Hi Norbert,
I just confirmed with your sales and IT team that I am using the correct software (Coreform Cubit), so the issue must be something else. Can we keep looking into this?
Can you send an image of the entire About box from the GUI? It is found under Help/About. You will have to expand the box to get all libraries to display. This will allow us to determine the exact version you are using so we can try to replicate your issue.
Thanks,
Karl
Hi Karl and Norbert,
Did you get a sense of what the issue was after seeing the exact version?
Cheers
Hi @p89on – I’ve not been able to replicate your issue. We just released Coreform Cubit 2023.11 last week, would you be able to install this latest version and verify whether you’re still having issues?
Download from: Coreform Product Downloads
I downloaded it and run the journal file in the new version. See the license details attached as well as the exact journal file. I have run the file line by line and it is the meshing step (last line) where it crashes
Thanks for verifying, I’ll take a look
One comment: I find that often when working with “mega-spline” CAD models that autohealing with the rebuild option:
The command is:
healer autoheal volume all rebuild
That will change entity ids (since it creates new geometry) so you’ll need to reassign mesh sizes, but that does at least fix the issue you’re seeing with the crazy mesh in your first post. Use that command after you’ve finished creating geometry & before you start meshing, assigning mesh sizes, imprinting/merging for meshing, etc.
It might also fix things so that you don’t crash when trying @Norbert_Hofbauer’s solution.
When I use that command, the meshing step does not crash, through several of the volumes are not meshed (error message is ‘Cannot insert required triangle’). A few of the errors copy pasted below, the journal file is attached
Begin tri meshing 6 surfaces 95
WARNING: MeshGems has problem meshing surface 95
WARNING: The CAD face with id 95 cannot be meshed (error -1)
WARNING: The CAD face with id 95 cannot be meshed (error -5)
WARNING: The CAD face with id 95 cannot be meshed (error -5)
Completed trimeshing surface 95
WARNING: MeshGems has problem meshing surface 95
WARNING: The CAD face with id 95 cannot be meshed (error -1)
WARNING: The CAD face with id 95 cannot be meshed (error -5)
WARNING: The CAD face with id 95 cannot be meshed (error -5)
ERROR: No 3d elements.
ERROR: Mesh of Volume 17 is invalid.
Deleting invalid mesh.
To retain the invalid mesh next time, set keep invalid mesh on.
Completed meshing volume 18 with 327330 tets
Begin tri meshing 7 surfaces 95
WARNING: MeshGems has problem meshing surface 95
WARNING: The CAD face with id 95 cannot be meshed (error -1)
WARNING: The CAD face with id 95 cannot be meshed (error -5)
WARNING: The CAD face with id 95 cannot be meshed (error -5)
Completed trimeshing surface 95
WARNING: MeshGems has problem meshing surface 95
WARNING: The CAD face with id 95 cannot be meshed (error -1)
WARNING: The CAD face with id 95 cannot be meshed (error -5)
WARNING: The CAD face with id 95 cannot be meshed (error -5)
ERROR: No 3d elements.
ERROR: Mesh of Volume 19 is invalid.
Deleting invalid mesh.
To retain the invalid mesh next time, set keep invalid mesh on.
Begin tri meshing 10 surfaces 117
WARNING: MeshGems has problem meshing surface 117
WARNING: The CAD face with id 117 cannot be meshed (error -1)
WARNING: The CAD face with id 117 cannot be meshed (error -5)
WARNING: The CAD face with id 117 cannot be meshed (error -5)
Completed trimeshing surface 117
WARNING: MeshGems has problem meshing surface 117
WARNING: The CAD face with id 117 cannot be meshed (error -1)
WARNING: The CAD face with id 117 cannot be meshed (error -5)
WARNING: The CAD face with id 117 cannot be meshed (error -5)
ERROR: No 3d elements.
ERROR: Mesh of Volume 20 is invalid.
Deleting invalid mesh.
To retain the invalid mesh next time, set keep invalid mesh on.
ERROR: unable to generate mesh with hpc tetra
Volumes 15, 18 meshing completed using scheme: tetmesh
Generated 564905 tets
ERROR: Volumes 16, 17, 19 to 21 meshing unsuccessful using scheme: tetmesh
Meshing time: 126.736102
ERROR: 5 volumes did not mesh : Volume 16, 17, 19 to 21
geometry_only copy.txt (154.5 KB)
Comment out the mesh surf with z_coord=0 command — just mesh all the volumes “freely”.