.STL file supermesh and meshing

Hello,  I'm new in FEFLOW modeling. :D

The thing is that I have to model a  tunnel in the rock mass, and I'm starting with very simple geometry first.

I have a perfect meshed .stl file, i.e, without self intersections, and so on. So when it's time to mesh it in FEFLOW, It doesn't give error of self intersections, and I get a mesh.

The problem is that I need to separate zones, to set different properties for the tunnel, for certain geological lithologies, and so on. My .stl supermesh that I import already is 'separated', but when I import it on FEFLOW it only shows me that I have only one polygon, and therefore only one zone.

I've seen already that when you import a supermesh from a geological model (GOCAD for example), it already has information about polygons and so on, so it's easy to set properties to the different volumetric or surface zones, as shown in this video:

https://www.youtube.com/watch?v=Vz7T04dc7xI  min: 14:20

The question finally is, how can I separate the volume, surfaces and so on to set the properties for these entities later on? What do I have to do to my .stl supermesh to separate it into several polygons?

Is there a way for .stl files, right?

Thanks in advance. :)

If the volumes are already perfectly separated, just import at least one point per zone as a point in the supermesh and declare it a 'Region Marker'. With this, TetGen will sort the resulting tets into groups for each zone.

Peter, thanks so much.

Finally I could generate different zones. I will be asking more questions in this forum as my research progresses.

Thanks again and have a nice weekend. :)

Thanks for the positive feedback, and have a great weekend, too!

Dear Peter. Hello again. :D

As I've told you, I solved the problem with volumetric regions thanks to you, but I'm still struggling on how to generate surface zones, like interface tunnel-rock for example, or other contacts, or perhaps also the boundaries of the model.

Do you have to put a point in the interface you want, and declare it as a region marker too? I must apologize beforehand if so, because I haven't tried this option yet.

Thanks so much in advance.  :)

I've just tried by adding some points in the interface, and declare these points as 'Points-add-ins' and then grouping by name.

This is quite cool solution, but I would have to import hundreds of points per interface, according chosen Super-mesh.

Is there a different way, dear Peter?

Thanks!

As you get the zones as volumetric zones, you can use FEFLOW to convert selections in between elements, nodes and faces. By intersecting the selections for different zones you can then get the interfaces for the geometry type you need.

Thanks Peter!

Now I'm completely clear on this,

Best regards and have a nice weekend!