[Gmsh] conformal mulitregion meshing from commandline +step file import

[Anan Im]

27.10.2015, 13:10, "Zenker, Dr. Matthias" <Matthias.Zenker at erbe-med.com>:
> Hi,
>
> the mesh in the picture in the post http://forum.freecadweb.org/viewtopic.php?f=18&t=10846&sid=2d71e90e5bc6cb707fb96796681a84ca&start=10#p103981 looks conformal, but if I open it in gmsh, it looks loke a single body. In the picture in the post http://forum.freecadweb.org/viewtopic.php?f=18&t=10846&sid=2d71e90e5bc6cb707fb96796681a84ca&start=20#p103993 is not conformal at the interface.
> By "conformal" I mean that the triangles and nodes on both touching faces are the same. Only then you can have heat or current flow between bodies. 
>
> Matthias
Yes,  basically agree on your conception of "conformal". Thanks for that clarification. It was expected and helped. Others speak of "conforming"; "conformity" (like gmsh man) one reads. Guess I goes all down to the very same, does not it?
But then there is extra info such as region, or boundary by. There the question is: If there is a standardized format to be be qualified as "conformal"? This mean basically ready for solving. How would such a mesh preparation state be called? Not at all?
Well and then there was found a definition, where the claim to have a patent on 
http://www.sonnetsoftware.com/support/help-current-version/help_topics/what_is_conformal_mesh_.htm
conformal meshing: "Conformal meshing is a technique which can dramatically reduce the memory and time required for analysis"
Could you please help to sort those terms in? tia.


>If the OCC functions for connecting/sewing faces work only for flat faces as suggested in the thread you cite, they are next to useless since curved faces occur in 3D.
It is rumor...

It seems that at the moment only Salomé can sew such faces - but AFAIK Salomé uses OCC also, so there must be a way...

Would be a help, if some gmsh experts could drop a commentary on:
(As I see there are several ways of representing and  controlling multiregion (zones,bodies), thus importing and exporting signaling. 
-Given the cited command line where along do the ready-to-solve data flow? And what is the typical problem about it all, if there is?
>gmsh face_com_step.step -2 -format unv -o compound_of_faces.unv -optimize -string "Geometry.OCCSewFaces=1;" -string "Mesh.CharacteristicLengthFactor = 1.5;"
-What is about "Names" of such "Groups" for the (external) solver to identify? How are they introduced?
-And yes, what is about bespoken unflat interboundary faces, can gmsh handle it multiregionally or can it not?
Thanks in advance