    mesh, radial trisection
$      enforce periodicity
      trisection blocks, 1
      zmin 0.0
        numz 1
          zblock 1 0.001 interval 1
        numr 2
          rblock 1 0.002 first size 0.0005176380902 
	  rblock 2 0.003 first size 0.00103527618 last size 0.002588190451
	numa 1
	  ablock 1 90. interval 2
      end

      set assign
        nodeset, ilo, 1  $ center of the mesh
        sideset, ihi, 2  $ outer radius of mesh
        block sideset, ihi, 3, 1  $ outer radius of wire
      end
    end

