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Hi everyone,
I'm a new user for Blukenue. When I generate a mesh file by using T3 mesh generator, there appears many over constrained and overstretched triangular elements near the long and narrow island. How can I make them more uniform and remove the over constrained element.
Here attached are the sketch images and .t3m files.
Many thanks!
Lin

Hi,

I haven't checked your zip file.
But have you tried to resample the line?

Try resampling it and uncheck the option "Resample Outline" before you run the T3Mesh Generator

And also, what is that long red line on the lower right side of the inner island?

Hi,
Thank you for your reply and it works.
The long red line on the lower right side of the inner island is actually a narrow long island.
However, there are still a lot of over constrained elements in the mesh. How can I fix them? Removing them one by one using the 'delete selected element' in T3mesh tool bar?

Best regards,
Lin

Change the local criteria...

Please upgrade to at least BK 3.12.25 - beta and you will now see that the meshing was not complete. In fact, the estimated number of MAXIMUM nodes needs to be increased from the default estimated count of 140,950 up to something around 500,000 nodes.

After increasing the estimated maximum node count to 500,000 the meshing will complete. However, you will then discover some missing triangles along your long narrow island.

This is a zoomed portion of the result I get via BK 3.12.25 - beta using the t3m file you shared:



Kindly... Alan

PS In the future I may investigate further to understand why some triangles are missing. Stay tuned...

Hi Lin,

As Christophe suggested...
I suggest you change the local density along the narrow spit.
The easiest way would be to reseample that island's line to something close to half the width of the spit and provide it to the mesher as a hard line.

NOTE:
In general it is advised that if you wish to generate a mesh with areas of widely differing detail that you build it up in stages. Create a mesh of each detailed area separately. Then include them as submeshes to the final.

Alan: It appears that the estimated node count by the new calculation method is a bit over restrictive.

Hope this helps... Martin

Hello again,

There is always more than 1 way to skin a cat but here is an example of how you can utilize Blue Kenue efficiently to create a quality mesh.

Of course without knowing the exact processes you are trying to capture in your model I can only guess at what your optimal mesh would look like.

I've attached 2 t3m files.

The first one, "IslandOutlineResampler.t3m" creates a new IslandOutline that "reasonably" captures the geometry of the island in your domain. NOTE: this does not create a mesh. It simply uses tools built into the mesher to resample the island outline.

The second "FinalMesh.t3m incorporates the new IslandOutline as a "HardLine" and also provides a pointset from which the spatial variability of the final mesh density is interpolated.

Hope this helps... Martin

And here is the resulting mesh generated with BlueKenue V3.12.25



It seems that this forum will not allow attachments greater than 2 MB
so I had to rewrite the final mesh file with an older version of BK that
doesn't retain so many trailing 0's for the coordinates.
But rest assured this mesh was actually created with the absolutely latest
version of BK.