I’ve uploaded my mesh CAD file from fusion 360 and its working well, except for the fact that there are two faces that should be one single face. They are part of the same body (so the boolean feature does not work). This is preventing me from setting the two faces as a single seed in the internal tool. Is there a way that I can either merge the faces or use two separate faces as the seed boundary?
To see the problem: Hide the face of the long tube, the two inner faces of the tube need to be one single face in order to use the internal flow feature.
Hi @tmahoney, thanks for posting on the forum and welcome to the SimScale Community 
I’ll take a look at your project and get back to you in a few 
Best,
Igor
1 Like
Hi again @tmahoney,
I’ve just noticed that you’re importing your CAD as an STL file, is there a way to export it as STEP or Parasolid? This will probably solve your issue with the faces.
Best,
Igor
When I exported my mesh from Fusion as a STEP file and uploaded it to simscale I got this error: The file could not be imported as valid geometry based on the provided geometry format. Please try to export a different format or contact our support for assistance.
Error Code: 4bc6ee92
I don’t see an option to export as a parasolid file, however that may be a miss on my part.
Is the file originally an STL? We usually advise users to avoid that file format for simulation due to the facet splitting issue
Yes the original file is an STL mesh. We hired an outside company to develop the file. What format is best to have it in?
Usually either STEP or Parasolid. If you have an original STL and try to convert it to Parasolid/STEP, you’ll face these facet splitting issues unless your geometry is very clear-cut (like a box).
I made a new file with a STEP file and I’m still experiencing the same issue where the internal part of the pipe is in multiple different faces. Do you know another tool that I could use model the internal geometry for a simulation?
Hi @tmahoney,
I see that your CAD is now split in way less faces that seem better suited for simulation. Were you able to solve the issue? If not, could you send some screenshots of the specific faces you want to eliminate?
Internally, we use OnShape for CAD. Maybe trying to get some results over there is a good option!
Best,
Igor
Yes I was able to figure it out. For anyone who may be having the same issue, I realized that I was not using the internal flow tool right. Only one face that runs along where the flow will be needs to be selected as the seed and the boundary conditions are just the ends of the pipe. Much simpler than I thought!
1 Like
Yes, that’s correct! Sorry for missing that, boundary faces will be the ones in contact with the boundaries of the flow and the seed face is an internal face.