mesh
  radial
  numz 2
   zblock 1 10.0 first size 1 last size 2
   zblock 2 10.0 first size 2 last size 1
  numr 2 initial radius 1.
   rblock 1 10. first size 1. last size 2.
   rblock 2 10. first size 2. last size 1.
  numa 1
   ablock 1 120. interval 10
 end
end
