How to build a structured mesh?

General Discussion
1

Hi everyone!
Can you suggest to me a way for having a structured mesh for my geometry?
The system’s geometry is a honeycomb-like shape.
Initilly i tried with just one hexagon: I have made a first mesh with the command “buildmesh” with just one element for border and I have obtained a good structured mesh (as you can see, there are 6 triangles inside one singular hexagon) then, in order the increase the number of elements while still hold this kind of structure, I have used the comand “trunc”.
Unfortunally, if I try to use the same procedure for a more-complex geometry, the first mesh generation (the one that should have only 6 triangles elements inside a singular hexagon) have this weird behaviour (see linked immagine). Some hexagones have a wrong element distribution, with a bigger center triangle.

Screenshot_20221208_154454
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Screenshot_20221208_154632
Screenshot_20221208_154632874×705 226 KB

Can you help me, please?
Thank you in advance!

2

I recognize that this doesn’t answer your question, but why is it that you want a structured mesh?

In an effort to provide a more constructive answer, might I suggest you try using the adaptmesh function to control the tolerated aspect ratios / vertex angles…

3

In few words, i should reproduce a result generated by another softwar that use this kind of structured mesh.

Thank you for your answer! I arleady have tried to modify “manually” the mesh parameters, unfortunally this is the best result reached.

Screenshot_20221208_185806
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Even if hmin is fixed, some elements has smaller lenght sides, same problem even when “thetamax” is defined!

4

But shouldn’t your results be mesh-independent?

I generally use GMSH to generate meshes and import them into FreeFEM. GMSH may offer more precise control of angles/aspect ratios

5

Yes it should be grid-idependet, that’s why once the coarse mesh is created correctly, I would increase the elements number by usign “trunc” comand!

Thank you for your Answer! I will try GMSH!

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