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Hi everyone,

I have an existing mesh wich i like to split in smaller parts.
Is it possible, on BlueKenue, to draw a line where I'd like to divide the mesh in half, and split the mesh along this line, defining this line as a new boundary?

Except the nodes near the line wich have to change, I'd like to keep the same nodes and elements inside the mesh

I didn't find such a possibility in BK manual or in another topic.

I draw a scheme in attached files of the result I'd like to obtain

Have a good day,

Antoine

Hi Antoine,

You can polygon off the area you want to keep in Bluekenue. Then use TOOLS - T3 MESH - EXTRACT SUBSET. Alternatively you can put a polygon over the area you want to delete an use EDIT - T3 MESH - DELETE ELEMENTS IN POLYGON.

If you want to make a nice straight boundary delete more than is required. Select the clipped mesh and use TOOLS - T3 MESH - EXTRACT EDGES (SHORELINES), this will create a polygon of the nodes around the outside of the clipped mesh. You'll have to edit the polygon (spilt polygon and just keep line on the boundary you want to extend), then make a line of the extra area. Resample the line to mesh resolution you require. Append the model land boundary and new extra area line, then close line to make a polygon. Create a new mesh of just this area (turn off resample outline). Then EDIT - T3 MESH - MERGE MESH

Hi greeve,

Thank you a lot for your answer, it helped me so much.
Now, I just have a problem creating the new mesh of the extra area. Despite fixing the border nodes of the original mesh (green on the picture) as hardpoints, the nodes of the new mesh (blue) are not created on the same points despite several tries with differents Edge Length.

Auto-adjust nodes after merging the two meshes doesn't solve the problem either.

Antoine.

The problem is on the mesh generation
If the nodes are fixed, they should be in the resulting mesh so you probably missed something (uncheck resample outline probably)

Regards

Hi c.coulet,

The option resample outline was the solution, thank you.

Antoine

Hello All,

I am trying to cut a piece of an old mesh and put a new, regridded part on there. I managed to extract subset from the older mesh. Later on, I extracted the edges of the new subset and used it as an outline for a new t3 mesh generator.

Oldmesh:



Desired mesh:



After doing that, I have deleted all elements from the old mesh inside of the new outline and merged the two meshes. However, some unwanted boundaries stays there even after merging, put as submesh and create a new mesh again.



What am I missing here?

Best regards,

Hi Jose,

Are you using the latest version?
I just performed this exact operation successfully with V3.12.26

And, did you use "Edit->T3 Mesh->Merge Mesh"
Then use "File->New->Boundary Conditions (Conlim)..."

Not sure if this would make a difference but try saving the Mesh with the hole cut out and the new submesh.
Then reload these files and try to create a new Boundary Conditions object...

Martin

Hi Martin. I was using the stable version, 3.3...Now I changed into the version you mentioned and worked beautifully.

Thank you so much for your help and congratulations on the great work with Blue Kenue.

with the best regards,

Hi Jose,

Glad it worked out for you.
Alan Barton is the one to thank for all the latest improvements.
I've been retired for 10 years and just very occasionally poke around here.

Cheers... Martin