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Hi all,
After generating the mesh in BK I tried to set up a new case file with Fudaa. While preprocessing the geometry file Fudaa returns this error:

"SEVERE: Erreur lors de la génération de la frontière. L'indice 1523 n'a pas de voisin"

I attach an image of mesh with node 1523 highlighted. Does anyone know how can I avoid this error message?

Kind regards
Marcin Kawka

Hello,

What is BK (Blue Kenue ?). It seems that you have a mismatch in the mesh connectivity, and this mismatch is seen by Fudaa. So probably this has something to see with your way of generating the mesh with BK ?

Jean-Michel Hervouet

Hello,
Yes, this mesh was generated with BlueKenue, using T3Mesh generator, with Edge growth ratio 1.2, def. Edge Length 0.2, without resampling. I used hard points, density points and outline with varying point density. Should I use soft and hard lines instead points? Is there any other guide/manual about mesh generation in BlueKenue except standard Reference Manual?

regards,
Marcin Kawka

Hi Marcin,

Please post your t3m file here and I'll have a look at it.

Cheers... Martin

Here it is.

Please send the (t3m) file.
I need the Mesher parameter file to diagnose the mesh

Martin

Sorry, I included the wrong file previously

Hi Marcin,

A couple of observations...

1. The density points that you supplied all have a value of 0.0 so the node placement algorithm ignores the density.
2. You supplied hard points over the entire domain, again with values of 0.0
3. The default edge length you supplied is so very small (0.2).

This all over-constrains the node placement algorithm.
If you remove your hard points and density points and set the default edge length to around 2000 you will generate a better mesh.

Now on to your original problem...
Here is your original mesh showing the element IDs.


You can see here that the blue triangle is not actually defined as an element (It's a triangular island). I suspect that this is what FUDAA is complaining about. The old Blue Kenue version you are using (3.1.3) has a bug that allows this to occur.

One solution is to define a higher density at the head of your penninsula. Set the edge length to something less than the overland distance from coast to coast.

Martin

Hi Martin,

I have the same problem with my mesh when I merge my original mesh (which works normally) with another mesh into my island. I used the same resampled line to define my hard line to create the contour and as outline for my litte mesh I wanted to put into the island.

Moreover, how do you do to show the element IDs in BlueKenue ?

Thank you,

To show the element IDs in BlueKenue:
Select the mesh item -> right click Properties -> under the Display tab -> check Show Element Labels.
Cheers, Julien