Meshing of a cylinder containing a small hole on one face
 

Hello people,

I am new to ICEM and I am facing the following problem: I have to mesh a cylinder with a small opening at one face in order to simulate a bubble column
within an air-lifting reactor. In order to do that, I created a big cylinder and small circle near one of the two faces. Afterwards, I projected the circle on one of the faces of the cylinder, then I trimmed the big face with the projected circle, and finally I created two surfaces.
I did all the tutorials of the tutorial manual but I have still no idea how to do that :(. I would like to create a structured mesh if it is possible. The dimensions of the big cylinder are: Height 50 cm, Diameter 5 cm. The diameter of the small circle is 1 mm. I do not think that it is difficult, but I don't know how to do that.
Can anybody help me?

if you have solved this problem can you explain