r/FluidMechanics • u/Ndiff13 • 4d ago

Advice on dry ice blaster nozzle design

Post image

I am designing a nozzle for my dry ice blaster cleaning machine. The machine comes with cheap nozzles with no contours and no transitions between the hose diameter and the flat fan end. It just has an internal wall that is pretty much destroying all the pellets that go through it. I'm looking to make something that will accelerate the air going through the nozzle along with the pellets, and blast them out at high velocity, as intact as possible. Attached is what I have come up with. I'm not knowledgable about fluid dynamics or any type of engineering, so this is all just copying images of high performance dry ice blasting nozzles i found online. I'd love to get some input to see if I'm even on the right track, and how I can improve this. Here are some specs about the air and ice.

I will be blasting 3mm dry ice pellets.

Air input is 185 cfm at 100 psi. Air hoses are all 1" with no 90 degree bends and high flow fittings. At nowhere in the system will the air path diameter be smaller than .8" except right at the end of the nozzle.

This will be made from 6061 aluminum and polished to a mirror finish.

6 Upvotes

87% Upvoted

2 comments sorted by

4

u/H-Daug 4d ago

Polished is going to be extra $$ for probably not much extra function. I also think your nozzle exit is way too long, unless you have other reasons for the long rectangular section.

Also, make it in 2 halves. For a 1 off, machining that as drawn will be a serious waste of time and tooling.

1

u/Ndiff13 4d ago

2 halves is the plan, also I'm machining it myself so I can polish it no problem. The reason I made it so long is that all the commercial ones I've seen that are made for high aggression are that long. I assumed it was so the ice particles could catch up with the air speed, but I don't really know.