This project was inspired by many things. Large commercially made vortex cannons are used (theoretically) to disrupt hail formation and prevent damage to farmland. German scientists during WWII also constructed a large vortex cannon designed as an anti air gun. The plan was to use a powdered fuel that would mix and ignite within the vortex ring, allowing it to increase in strength as it was fired into the clouds. The purpose in that case was to create an impact with allied aircraft powerful enough to snap the wings off. It never did see use. In a future video I may try integrating a fuel into the vortex rings just to see if the idea really had merit.
In any case this project was an interesting one, and a great first project to film with my new high speed camera. Leave my some feedback in the comments!
The chamber I used to fuel this vortex cannon is approximately 18 inches long, 4" diameter pressure rated PVC pipe. I used a 4" x 2" reducer, and then another 2" x 1.5" reducer to bring the diameter down to match the size of the coupling mounted to the vortex cone.
I've found that antistatic spray works quite well as propellant, and doesn't leave the sticky/stinky residue of spray deodorant. Metered propane would be a vast improvement on the design, that may be a future modification.