Meshing & Cubit Not Responding

Coreform Cubit Meshing
#1

test.sat (3.9 MB)

Hi Cubit Team,

I have encountered two issues while trying to mesh .sat geometry:

  1. Cubit doesn’t seem to be able to mesh the attached geometry, while Abaqus has no problem meshing it.
  2. Once Cubit meshes at least a part of the geometry, it becomes unresponsive for about 15 to 30 minutes before I can work on the file again.

I understand that meshing might be a bit difficult, but the fact that Cubit becomes unresponsive after meshing makes it unusable. Can you please look into this? Maybe I’m doing something wrong?

Many thanks.
Ondrej

#2

Hi Ondrej,
there are some volumes that needs the scheme manually set to polyhedron. As they are not automatically hex meshable.

grafik
grafik1119×637 46 KB

So prior to meshing all volumes we will first set the polyhedron scheme for some volumes and mesh them before we can attempt to mesh the rest.

#!cubit
reset
import acis "test.sat"
imprint vol all
merge vol all
Volume 7, 8, 10, 12, 18, 22, 26, 28, 30, 33, 35, 43, 44, 46, 48, 51, 53, 58, 62, 64, 66, 68, 70, 76, 78, 80, 85, 86, 88, 94, 96, 98, 103, 104, 153, 154, 156, 169, 170, 214, 215, 228, 239, 240, 300, 301,318, 319, 1265 to 1288 scheme polyhedron
mesh vol 7, 8, 10, 12, 18, 22, 26, 28, 30, 33, 35, 43, 44, 46, 48, 51, 53, 58, 62, 64, 66, 68, 70, 76, 78, 80, 85, 86, 88, 94, 96, 98, 103, 104, 153, 154, 156, 169, 170, 214, 215, 228, 239, 240, 300, 301,318, 319, 1265 to 1288
mesh vol all

grafik
grafik1920×1023 234 KB

Does this already work for you?

How did you try to mesh it?

#3

Hi Norbert,

Thank you very much for your quick reply. I started with automatic meshing just to check if it would work, but I didn’t get the chance to improve the mesh because the file became unresponsive. Has this happened on your end as well? It repeatedly happens to me whenever I try to mesh after importing the file. Your approach clearly works, but I’m unsure how you determined which volumes needed to be set to the polyhedron scheme. Could you please explain that in more detail?

Thank you,
Ondrej

#4

Hi Ondrej,
which version of cubit are you using? I did use the current release (2024.8).

When i import the .sat and mesh all volumes it takes 1 minute until meshing is finished. If your machine is a bit slower the gui can be unresponsive during meshing but it should be responsive after meshing.

When i meshed every volume some failed. I just used the failed volume ids that cubit printed out and checked their geometry. The polyhedron scheme fits perfect for the geometry of the failed volumes.

grafik
grafik1564×1067 77.2 KB

#5

Thank you, Norbert, for the explanation — that makes sense. I’m also using the newest version of Cubit, and meshing takes only about one minute, but then Cubit becomes unresponsive (see picture below). There are enough resources on this workstation, so I don’t think that’s the problem. What about the “Working Directory”? In my case, it is set by default to a network drive. It is very fast, so it shouldn’t be an issue, but could it be?

image
image2153×1584 304 KB

#6

Hi Ondrej,

I’m seeing the same results as Norbert. It works for me. I tried running your problem in Linux inside the debugger, but there were no obvious slowdowns. I ran it in Windows and it worked there as well.

My one thought is that it might a graphics card issue. You can try turning off all the extra processing while you are running the process. Here are the changes to the journal file.

  1. Turn off informational and warning messages because I/O is always slow.
  2. Turn off the graphics rendering while running the process.
  3. Turn off undo because that is doing I/O again and trying to write to disk.
  4. Add a timer to see how long the whole process took

At the end of the process, I turned them on again. The total time on my Windows machine for a single run was ~6.8 seconds. The time will vary somewhat from run-to-run depending on the computer states at the moment.

reset
import acis "~/Downloads/test.sat"
timer start
graphics off
set info off
set warning off
undo off
imprint vol all
merge vol all
Volume 7, 8, 10, 12, 18, 22, 26, 28, 30, 33, 35, 43, 44, 46, 48, 51, 53, 58, 62, 64, 66, 68, 70, 76, 78, 80, 85, 86, 88, 94, 96, 98, 103, 104, 153, 154, 156, 169, 170, 214, 215, 228, 239, 240, 300, 301,318, 319, 1265 to 1288 scheme polyhedron
mesh vol 7, 8, 10, 12, 18, 22, 26, 28, 30, 33, 35, 43, 44, 46, 48, 51, 53, 58, 62, 64, 66, 68, 70, 76, 78, 80, 85, 86, 88, 94, 96, 98, 103, 104, 153, 154, 156, 169, 170, 214, 215, 228, 239, 240, 300, 301,318, 319, 1265 to 1288
mesh vol all
graphics on
set info on
set warning on
undo on
timer stop

Thanks,
Karl

#7

Thank you, Karl for looking into this - it helped. Now I can keep working with the file without needing to wait for 20 min after meshing.

Many thanks,
Ondrej