This may be a simple question about meshing in Gambit. I have a volume which is basically a rectangular prism with a frustrum subracted from it, where the void is connected to the side and flares inwards. I try to mesh the volume automatically using gambit where it trys to apply a Hex\wedge grid. It seems I've done something wrong when creating the geometry so I get this error:

ERROR: Dual enclosed loop projections not implemented yet. Volume volume.1 could not be meshed. Try connecting interior holes in source faces to the exterior and mesh again.

But what is the interior hole and what are the source faces?

Do not know where to start here.

Any help would be appreciated.

cheers,

Matt.

Gambit tries to apply the Coopertool here. Check the manual how the Coopertool works: it needs to have a subvolume that resembles a barrel with two endcaps. These caps are the source faces. If you select a volume to be coopered Gambit will show you what it thinks are the sourcefaces (click the 'sources' button).

One restriction in the coopertool is that you can't have different 'holes' in both the source and the target face because than you wouldn't be able to construct the logical barrel that the coopertool needs. The easiest way to look at it is that it should be possible somehow to project the source face onto the target face. If you can't do that, Gambit will report the "Dual Enclosed Loop Projections error".

You're welcome Matthew. I think a lot of confusion could be avoided if the Gambit error messages weren't as cryptic as they usually are.

You were getting a 'Dual enclosed loop projection implementation' (???) error, which actually means source face can't be projected onto the target face.

Another good one is 'Splitting of existing meshes on source faces is not implemented yet'. This really means that you have to have an empty target face when using multiple source faces during Coopering.

In another error message, users are told to "Turn mesh_flags_incremental_display default on." (???) because of an "Impossible edge mesh/face scheme combination." Here there is usually a mixup between face vertex types and the meshing scheme.

After so many hours with Gambit I have learned to recongize the real problem I have from the type of error message I get, but much time could have been saved if the error messages would have been clear and would have included possible solution strategies.

[ritwik]

Hi Erwin,
Could you elaborate on the error : Splitting of existing mesh on a source face is not implement.
The reason you said is "There has to be an empty target face". Does that mean one target face shouldn't be meshed?
I meshed all my faces and then tried to mesh using Cooper for the volume. But it gives me the error (wrt a source face).
Please do suggest!
Thank you!

[Mohsin]

hello

I get the same error:

error : Splitting of existing mesh on a source face is not implement.

Could you explain the reason?

Thanks