Solve on face of 3D stp file

Netgen
,
1

I have this special geometry I want to solve on, as to import it I created a slab version of the step file (see attached) and selected the face for meshing
2DICRHSlab.step (52.9 KB):

if stp:
    #what we want to do: https://forum.ngsolve.org/t/selective-mesh-on-step-file/2230
    from netgen.occ import *
    geo = OCCGeometry('../../../../data/TOMAS_data/2DICRHSlab.step')
    logging.info('Extracting face 16')
    shape2 = geo.shape

    shape2.faces[15].name = "TheOne"

    rt = Glue (shape2.faces["TheOne"])
    geo = OCCGeometry(rt)
    logging.info('Generating the mesh')
    with TaskManager():
        mesh = Mesh(geo.GenerateMesh (maxh=MAXH))
    mesh.ngmesh.Scale(1/1000)
else:
    import netgen.geom2d as geom2d
    from netgen.geom2d import CSG2d, Circle, Rectangle

    geo = CSG2d()
    VesselWall = Circle( center=(0+0.78,0), radius=0.26, mat="Plasma", bc="wall" )
    CircleWithAntennaRadius = Circle( center=(0+0.78,0), radius=0.215, mat="copper", bc="Antenna" )
    AntennaCut1 = Rectangle( pmin=(-3+0.78,-1), pmax=(0+0.78,1), mat="copper", bc="cut" )
    AntennaCut2 = Rectangle( pmin=(-4+0.78,0.21*np.sin(np.deg2rad(40))), pmax=(1,1 + 0.21*np.sin(np.deg2rad(40))), mat="copper", bc="cut")
    AntennaCut3 = Rectangle( pmin=(-2+0.78,-1 + 0.21*np.sin(np.deg2rad(-40))), pmax=(1,0.21*np.sin(np.deg2rad(-40))), mat="copper", bc="cut" )
    CircleWithLessthanAntennaRadius = Circle( center=(0+0.78,0), radius=0.210, mat="copper", bc="Antenna" )

    Antenna = CircleWithAntennaRadius - CircleWithLessthanAntennaRadius - AntennaCut1 - AntennaCut2 - AntennaCut3
    System = VesselWall-Antenna
    geo.Add(System)
    logging.info('Generating the mesh')
    with TaskManager():
        mesh = Mesh(geo.GenerateMesh (maxh=MAXH))

Draw (mesh)

Even though these two meshes look like the same kind of construction, when creating a HCurl and Hdiv,
the test functions of the first (with stp) are 3D instead of 2D. How can I make the face ā€œ2Dā€? Or is there an easier method of importing 2D structures?

2 
OCCGeometry(rt, dim=2)

should do the trick

also Iā€™d already scale the geometry, then you can also curve the mesh toward the geometry:

from netgen.occ import *
from ngsolve import *
geo = OCCGeometry('2DICRHSlab.step')
shape2 = geo.shape

shape2.faces[15].name = "TheOne"

rt = Glue (shape2.faces["TheOne"])
rt = rt.Scale((0,0,0), 1/1000)
geo = OCCGeometry(rt, dim=2)
mesh = Mesh(geo.GenerateMesh ())
mesh.Curve(4)
Draw(mesh)

best,
Christopher

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