Aksrockets
Now with 8% more aluminum
- Joined
- Apr 1, 2011
- Messages
- 3,505
- Reaction score
- 14
That should almost say it all.
A friend from UROC and I are in the process of designing an extremely high performance 54mm based around PR FWFG or FWCF tubing. This build thread will document our findings and process during construction.
Short intro:
Build rocket. Go fast. Much fun.
Long intro:
Motor design: The motor case / airframe tube will be either filament wound fiberglass or filament wound carbon fiber, depending on our burst tests and strength testing. Since the TG of PR tubing is much less then the softening point of aluminum, extra steps will be taken to ensure that the casing will not take much heat. The way we plan to do this is with a monolithic grain geometry with inhibited ends (ignore the drawing). This means that the burning surface area of the propellant will not reach the liner until the very end of the burn. We will also be using a propellant with a low metal content, which should remain relatively "cool" compared to other propellants. Of course these measures to insure case protection come with setbacks. A low metal content means a low ISP and less performance. A monolithic grain geometry means a low initial KN and a high max KN (although this depends on nozzle design). Overall, I think the tradeoffs are worth the extra protection.
Another important topic is burst pressure. Since we don't know the burst pressure with PR tubing, we'll be doing destructive tests to figure that out. Final motor design plans can't be made until we have that data.
Besides motor design, the rest is very simple. CF fins, a few layers of T2T. The deployment design will be similar if not identical to my "Peacemaker" build last year. I was pretty happy with how well that worked.
That's about all i've got for you guys right now. Fear not! Even though this is an EX build, I'll be careful not to talk formulas or specifics, though I may post a picture of propellant casting or two.
Bye.
Alex
P.s. This is for Aeronaut 2015
Last edited: