Node definition in tetrahedral mesh
Node definition in tetrahedral meshPosted by Carlos Melendez at September 06. 2012
I want to mesh a solid with tetrahedrons and predefined the location of some internal nodes.
What I have done so far is first define vertices of the body, edges, then faces, afterwards a closed shell from the faces and finally the body. Then Salome meshes the body and therefore additional internal nodes are created. What I want is these nodes include certain nodes with certain coordinates that I want.
In the postprocessing I could move after meshing the nodes that are located next to my desired nodes, but this may cause problems if finite elements overlap.
Can anyone help me please??
Re: Node definition in tetrahedral meshPosted by Saint Michael at September 06. 2012
You need to create vertices (points) at needed locations, add them to your body using Partition( [body],[vertex1, vertex2...]) and compute the mesh using Tetrahedron(NETGEN) or Netgen 1D-2D-3D algorithms.
Re: Node definition in tetrahedral meshPosted by Carlos Melendez at September 06. 2012
Hello St. Michael,
Thanks a lot for your quick answer! I have tried to follow your instruccionts, but I don't make it work.
I have tried two things:
- Partition of the solid and additional vertices - Compute mesh of partition using Tetrahedron
- Partition of a closed shell and additional vertices - Generation of body from partition - Compute mesh of body
New nodes generated are not located in the needed coordinates in any of the cases.
Re: Node definition in tetrahedral meshPosted by Chrys Lides at September 06. 2012
It seems to be an issue with Netgen-1d-2d-3d. Try to use this combination instead:
- 3D: Netgen 3d
- 2D: Netgen 2D
- 1D: Wire discretisation, local length.
Re: Node definition in tetrahedral meshPosted by Carlos Melendez at September 07. 2012
Thank you for your answer. I tried your instructions but I don't make it work either. The program stops working.
The only way I have found to have the needed points in the mesh is to choose the algorithm NetGen 1D-2D-3D to mesh the partition. But then I get one error: NgException at Surface meshing: Problem in Surface mesh generation. I get this error for two faces.