Im trying to build a mesh for flow over a really small cylinder in the centre of a large cylinder. Im confused about the best way to create a mesh around the cylinder in GAMBIT. Some of the tutorials for an airfoil talk about creating an ellipse around the airfoil, distributing same number of nodes on the airfoil edge and the ellipse edge and proceeding from there. How would this work for a 3-d cylinder? Say I create a cylinder volume over my inner cylinder and create equal number of meshing nodes on both the cylinders. Where do I go from here>

How small is the small cylinder? I had to create closely spaced 3D cylinders of 350 micron diameter and had difficulty meshing them. I changed the geometry to an octagon and it worked really great even when I used unstructured meshing.