How does a fan gun work, and what is needed for it to work.

Yes I would like to know also because im starting a fan gun project soon ,possibly.

I see that you have the same avatar as me. Got it from Google images.

There are three main components to a fan gun:

Nucleation nozzle(s)
Bulk nozzle(s)
Fan

The nuc nozzle(s) uses compressed air and a little water to create a stream of frozen mist for the bulk water to freeze onto.

The Bulk water nozzle(s) spray out a fine mist of water droplets.

The fan mixes up the two types of streams (nuc and bulk water), and gives it a nice big throw, to give it some nice hang time (more time to freeze before hitting the ground).

It is the same basic concept as a regular combo-gun, but typically uses more nozzles, less water pressure, and (of course) a fan.

Thanks for the info Goofy.