mesh
  radial trisection
  trisection blocks, 4
  zmin -0.00075
  numz 1
   zblock 1 4. interval 4
  numr 3 
   rblock 1 2.0 interval 4
   rblock 2 3.0 interval 4
   rblock 3 5.0 interval 4
  numa 1
   ablock 1 360. interval 32
 end
end
