Problems creating volume mesh

willful · February 16, 2016, 22:53

I am basically trying to repeat the thermal comfort manikin tutorial but with my own internal car model however the volume mesh keeps failing. I get the error message "Mesh is self-intersecting" I have read a few forum posts on it but cannot seem to find a solution.

I think some of the issue may be when assigning parts to regions as when I do this the Output says "no interfaces were created". I've attached a screenshot of the model with the surface mesh. Any help would be appreciated!

ggulgulia · February 17, 2016, 00:33

Hi William,

I am sure you've missed surface repairing and this is quite a complicated geometry for me to explain you surface repairing.

It will be really helpful if you could refer to some tutorials on surface repair.

Surface repair opens up when you select the highlighted image above. Over there you need to select Import Representation. A new window will open up. Click manage thresholds. In this select the 1st from top and last 3 from bottom (Intersecting faces, free edges, manifold edges and manifold vertices).

You have to make sure that these parameters are zero before you remesh the surface.

willful · February 17, 2016, 07:35

I did some surface repair although not sure if I did it perfectly. The thresholds you described are all 0. Face quality and proximity aren't though.

ggulgulia · February 17, 2016, 21:54

Hi,

In that case, you should go to the mesh continua, select the mesh model and make sure per region meshing is activated (in case a mesh continua is assigned to multiple regions).
Secondly you have to take care that the smallest mesh size is smaller than the smallest significant size that occurs in your mesh.
Thirdly I would also suggest you to delete the feature curves just before you start to remesh and create new feature curves ( make sure you remark the existing feature curves when you do so)

Please let me know if this was helpful.

Schwob77 · February 18, 2016, 15:29

You have 6 Regions but no interfaces. So even if you are successful with meshing e.g. by per - region meshing as already indicated, there will be no reasonable solution in the end as the region's don't exchange any fluxes. So the minimum thing you have to do is to create the interfaces.
As you don't have contacts under Geometry ->Parts->Contacts already the parts are not connected well with each other. That's why no interfaces are created when you assign parts to regions. So the better choice is to fix the connections between the parts by merge/imprint in surface repair or by extract volume operation e.g. In that way you get the interfaces automatically.
Maybe you should first do one of the surface preparation tutorials to get an understanding of contacts and interfaces plus meshing.

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February 17, 2016, 00:33		#2
ggulgulia Senior Member Gajendra Gulgulia Join Date: Apr 2013 Location: Munich Posts: 144 Rep Power: 13	Hi William, I am sure you've missed surface repairing and this is quite a complicated geometry for me to explain you surface repairing. It will be really helpful if you could refer to some tutorials on surface repair. Surface repair opens up when you select the highlighted image above. Over there you need to select Import Representation. A new window will open up. Click manage thresholds. In this select the 1st from top and last 3 from bottom (Intersecting faces, free edges, manifold edges and manifold vertices). You have to make sure that these parameters are zero before you remesh the surface.

February 17, 2016, 07:35		#3
willful New Member William Fulwood Join Date: Feb 2016 Posts: 4 Rep Power: 10	I did some surface repair although not sure if I did it perfectly. The thresholds you described are all 0. Face quality and proximity aren't though.

February 17, 2016, 21:54		#4
ggulgulia Senior Member Gajendra Gulgulia Join Date: Apr 2013 Location: Munich Posts: 144 Rep Power: 13	Hi, In that case, you should go to the mesh continua, select the mesh model and make sure per region meshing is activated (in case a mesh continua is assigned to multiple regions). Secondly you have to take care that the smallest mesh size is smaller than the smallest significant size that occurs in your mesh. Thirdly I would also suggest you to delete the feature curves just before you start to remesh and create new feature curves ( make sure you remark the existing feature curves when you do so) Please let me know if this was helpful.

February 18, 2016, 15:29		#5
Schwob77 Member Join Date: Nov 2015 Posts: 38 Rep Power: 10	You have 6 Regions but no interfaces. So even if you are successful with meshing e.g. by per - region meshing as already indicated, there will be no reasonable solution in the end as the region's don't exchange any fluxes. So the minimum thing you have to do is to create the interfaces. As you don't have contacts under Geometry ->Parts->Contacts already the parts are not connected well with each other. That's why no interfaces are created when you assign parts to regions. So the better choice is to fix the connections between the parts by merge/imprint in surface repair or by extract volume operation e.g. In that way you get the interfaces automatically. Maybe you should first do one of the surface preparation tutorials to get an understanding of contacts and interfaces plus meshing.