Anonymous - 2011-11-26

Hello,

first of all, thank you for providing such a gorgeous tool for meshing, Netgen really is great work!

I have a question regarding boundary conditions. I know, similar questions have already been asked, but I cannot figure out how to do my task.

I have the following file:
***********************************
algebraic3d
solid cube = plane (0, 0, 0; 0, 0, -1)
         and plane (0, 0, 0; 0, -1, 0)
         and plane (0, 0, 0; -1, 0, 0)
         and plane (9, 100, 140; 0, 0, 1)
         and plane (9, 100, 140; 0, 1, 0)
         and plane (9, 100, 140; 1, 0, 0) -bc=1;
solid cutplane1 = plane (4.5, 0, 0; -1, 0, 0) -bc=2;
solid cutplane2 = plane (9, 0, 0; -1, 0, 0) -bc=3;

solid cube1 = cube and not cutplane1 -maxh=2;
solid cube2 = cube and cutplane1 and not cutplane2 -maxh=2;

tlo cube1 -col=;
tlo cube2 -col=;
**************************************
In principal, it shall make two adjacent areas of cubes. I think, the cubes are ok.

But I would like to figure out, which nodes belong to the three big surfaces, i.e. the left outer surface, the "cutplane1"-surface and the right outermost surface.
Thus, I would like to assign unique boundary conditions to these surfaces so I can use the .neu-Output "surface elements" to determine, which nodes belong to these surfaces.

How can I do that?

Thank you so much for your help,
Patricia