[tkeskita]

Hello world,

I've been working on a new Blender based 3D mesh editing tool for OpenFOAM (and later on VTK) users: Unstructured Grids (UG) is an add-on for Blender 2.8 for importing, editing and exporting of 3D volume meshes composed of arbitrary polyhedron cells (a.k.a 3D unstructured grids). Editing includes tasks like moving of selected vertices, and assigning selected boundary faces to named patches. The add-on Imports and Exports OpenFOAM PolyMesh format.

The add-on is now at proof-of-concept level, and it seems to be working OK, at least for small and medium size meshes. Please feel free to try it out and discuss on this thread, thanks!

Here is example of current functionality. Boundary face assignment:



And here mesh modification by moving vertices:


BR,
Tuomo

[fusij]

Hello, thank you for this addon.

Can you move individual vertices? For example, if you have a faulty cell, you could edit the positions of the vertices of that cell.

[tkeskita]

Hi,

yes, you can move any vertex selection (and that's the only thing you can do to geometry currently). So if you know which vertices are bad then you could try to move those by hand. But if there are many bad cells it might be a lot of work.

PS. Currently I'm working on adding cell zone and face zone support.

[tkeskita]

FYI: Now cell zones are fully supported (using Blender vertex groups). Face zones are read, shown and exported as such, but creation/modification is currently unsupported, since it requires flipMap (face direction) support in GUI.

I also added a GUI: "UG" tab is available in Sidebar of 3D Viewport for mesh objects.

[tkeskita]

Some improvements regarding cell editing:

- Deletion of selected cells is now supported
- New cells can be extruded from face selection. This is currently WIP and very slow, but it allows interesting body-fit mesh cases. Here is extrusion (followed by Blender mesh twist) example:

[tkeskita]

FYI I wrote manual for the Unstructured Grids Blender Add-on, please have a look at https://unstructured-grids.readthedocs.io/

Looks like the images in previous messages are not showing up any more, those can be found also in the docs.

BR,
Tuomo

[tkeskita]

FYI I've added an experimental Shell extrusion method to the add-on. It allows extrusion of thin flat cell layers starting from a surface mesh. I tested it on a mesh generated with SnappyHexMeshGUI, and was able to produce this thin shell of boundary layers on top of Snappy mesh.

Disclaimer: The method fails (creates intersecting faces) when mesh has convex shapes and target thickness is too large, so this method does have limitations. The area marked with red ellipse in the bottom figure below would fail if more layers were added.

shell_extrusion_1.jpg


shell_extrusion_2.jpg


shell_extrusion_3.jpg


shell_extrusion_4.jpg


BR,
Tuomo