I found out how to mesh the contact planes of the coins after seeing this tutorial (code below):
web.pdx.edu/~gjay/teaching/mth610_2015.2/TutorialNGSpy.html
How to I extend the mesh over the Cylindrical sides and backs of the coins to form 3D meshes?
from netgen.geom2d import SplineGeometry
def Circle(geom,r, bc, left, right, maxh):
disc_pnts = [ ( r, 0), ( r, r), ( 0, r), (-r, r), (-r, 0), (-r, -r), ( 0, -r), ( r, -r) ]
disc_pnums = [geom.AppendPoint(*p) for p in disc_pnts]
curves = [ (disc_pnums[0], disc_pnums[1], disc_pnums[2]),
(disc_pnums[2], disc_pnums[3], disc_pnums[4]),
(disc_pnums[4], disc_pnums[5], disc_pnums[6]),
(disc_pnums[6], disc_pnums[7], disc_pnums[0]) ]
for p0,p1,p2 in curves:
geom.Append( ["spline3", p0,p1,p2],
bc=bc, leftdomain=left, rightdomain=right, maxh=maxh)
return geom
geo = SplineGeometry()
geo = Circle(geo, 4.0, 1, 0, 1, 0.1)
geo = Circle(geo, 5.0, 2, 1, 0, 1.0)
ngmesh = geo.GenerateMesh()
ngmesh.Save("large_coin_face.vol")
geo2 = SplineGeometry()
geo2 = Circle(geo2, 4.0, 3, 1, 0, 0.1)
ngmesh = geo2.GenerateMesh()
ngmesh.Save("small_coin_face.vol")