What is the function of the barrel of a Bunsen burner?

The barrel on a Bunsen burner is a metal tube that is screwed onto the burner's base, and has tiny holes known as air intake openings. The air intake openings are normally situated at the bottom of the barrel and are purposely put there to let in air.

I actually found the answer
It is to make sure the flame is at a suitable height. Thanks for trying though