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Good morning,

I'm setting up a model of a lagoon for my thesis project.

I have a problem when creating the conlim file.

For meshing the internal part of the lagoon, I:

-create the mesh for the channels first (see attached picture)
-create the first 'coastal strip' (see picture), using a closed line as SOFTLINE.
-then I create the final mesh using the T3 mesh and giving the meshes above as submeshes, in order to create the complete mesh of the southern part of the lagoon (see attached picture).

The problem occur when I create the conlim file, infact on the closed lines used as softline, it automatically generate a boundary line (see attached picture) that I can't delete.

Am I mistaking something in the mesh generation steps or is something else?

Is there a way to fix the problem without restarting?

Thanks in advance for the attention,

Andrea

Hi
In fact the problem occurs earlier, during the mesh generation but you see it only with the boundary condition...
It's hard to say where the problems comes from exactly in the different steps you follow to build the mesh.
Did you let the softline used for coastal strip in the final mesh generator?


Otherwise, maybe you could omit the step for the caostal strip and generate the global mesh directly in one step with only the channel mesh as submesh...


Regards

Hi Andrea,
It looks like for some reason the hole inside your coastal strip still appears as an island to the conlim generator. (Hence the internal conlim boundary segments) I don't recall for sure but I don't remember ever testing a situation where a submesh completely surrounded the mesh being generated.
You could try generating the internal mesh separately and then merging it with "Edit->T3Mesh->Merge Mesh...
Could you post your t3m file here so we can have a peek at it.
Cheers... Martin

Thanks for the attentio.

I tried three ways:

1) the way explained above
2) the way you suggest me
3) using the coastline as OUTLINE and the coastal strip line as softlines, giving the other mesh (including the coastal strip mesh) as submeshes.

With the first two ways I obtain the same results, with the third the mesher does not create the meshes over the coastal strip line (I expected that but it was for trying).

Any other ideas?

Regards

It does not allow me to attach the .t3m file neither the outline or the submeshes.

zip the files and attach...

Here are the files

Thanks for the reply,

About your question I consider the softline used for the coastal strip as the outline of the last mesher, but I also tried a different way but it does not change the results.

As you said, I omitted the step for the coastal strip and directly generated the final mesh, with the three channel as submeshes.
It works, even though the final results is a bit worst than the previous one.

Thanks a lot for the reply.

Regards,

Andrea

Hello again,

I'm facing the same issue and now I don't know how to overcome it.

I need to connect a river and the channel of the lagoon to the open sea
I explain all the steps used for creating the mesh:

1) I created the mesh for the channel(1) and for the river(2) (see fig1 attached)

2) then I created the first strip for connecting the channel to the river and the rest of the river (see fig2 attached).

3) then I created the mesh for connecting the sea to the river,channel ecc(see fig.3)

4)Lastly I merged all the meshes, and it seems to be ok (see fig.4)

5) when I create the conlim file (not because I nedd, but for check if there would be some problem), it makes a boundary line in the middle of the river (where the is the connession between the strip2, the strip1 and the river mesh) (see fig.5 and fig.6


Any ideas on how to overcome the issue??

Thanks again for the attention.

Regards,

Andrea

Hi Andrea,

It appears that somehow duplicate nodes and/or elements have been created.

Try carefully examining the node numbers and element numbers in detail in this area. (using Show Node/element labels) on the mesh properties page.
Then perhaps you can use the "Edit->T3Mesh->" menu commands to remove the offending bits.

Alternatively you could cut out a section of the mesh and then use the resulting "island" outline as a fixed outline to create yet another submesh to merge in.

My conclusion is that there appears to be a bug in the mesher or the merging functions and I apologize for that. Perhaps Alan Barton at the NRC can help with resolving that. Unfortunately I can't be much coding help as I retired 5 years ago and have no say or control over BlueKenue.

Alan?? Your thoughts??

Hope this helps... Martin