Issues in troubleshooting erros while using PyMAPDL to import a CAD file in .igs format

[IshaanS1]

I am attempting to import a CAD file in .igs format and open it in MAPDL via Python. The following code is based on one of the example scripts provided by PyAnsys. While I am able to import basic geometries with an issue (cube, cuboid, sphere etc.), on attempting to import a more complex geometry (a sector of turbine blades), I run into the following erro, for which I was looking for some guidance to understand and then troubleshoot:

The code for the same is provided below:

from ansys.mapdl import core as pymapdl
from ansys.mapdl.core.plotting import MapdlTheme
from ansys.mapdl.core import launch_mapdl
import os

ch_cwd = os.chdir(r"insert directory")
cwd = os.getcwd()
print(cwd)

# Step 1: Launch MAPDL
mapdl = launch_mapdl()
mapdl.aux15()
mapdl.igesin(fname = 'geom1',ext = 'igs')


mapdl.prep7()
mapdl.et(1, "Solid186")
mapdl.esize(5.0)
mapdl.vmesh('ALL')
mapdl.finish()
mapdl.eplot()


mapdl.lplot(
    show_line_numbering=False,
    background="k",
    line_width=3,
    color="w",
    show_axes=False,
    show_bounds=True,
    title="",
    cpos="xz",
)

[germa89]

Hi @IshaanS1

It seems to me that the geometry is not meeting the MAPDL quality requirements. I guess the only real solution is go back to your geometry and edit it to remove these degenerated areas.

If you must work in MAPDL, I would start with importing smaller parts of the same geometry (If you have them separated) with the idea of identify what area is causing the trouble.
If nothing works, you could try to edit the geometry in other CAD software, or open it with a mesher and export the mesh.

[IshaanS1]

Regarding cleaning the geometry, the errors mention surface 13 and the inability to create an area due to trimming errors. How do I identify these locations in the model? Would I have to do that in MAPDL or within the CAD software itself?

[germa89]

I would say in the CAD software itself.

[mikerife]

Hi @IshaanS1 what is the native file format of the CAD program used to create the geometry?
Mike

[IshaanS1]

I have Siemens NX installed locally on my device along with MAPDL and PyMAPDL and tried using the UGIN command. While the MAPDL window opens up it doesn't seem to recognize the geometry as is pointed out my the messages in the first attached image. Facing similar issues with the PARAIN command as well.

[mikerife]

Hi @IshaanS1 are you a commercial customer? If so can you share the parasolid file publically? If not publically could you as part of a standard technical support case?

[IshaanS1]

model3.zip

Apologies for the delayed response. I was trying to obtain permission to share the the parasolid/IGES file in question, but cannot since it is proprietary information. I have attached another file here I am having issues with.

[mikerife]

Hi @IshaanS1 there is no problem with that geometry...it's just not map meshable (must be a 4,5, or 6 sided volume). Try to sweep mesh it or use area concantenation first, then map mesh. Mike

p.s. have you tried parasolid or native NX prt file import into MAPDL? IGES should be the option of last resort.