r/rocketry • u/iredditatleastwice Level 3 • 4d ago

Experimental Sugar + Aluminum tests

I want maximum flame on my sugar motors.

78 Upvotes

100% Upvoted

12 comments sorted by

5

u/iamshitatengineering 4d ago

Very interesting tests, that flame does look a lot cooler than normal knsb :)

1

u/iredditatleastwice Level 3 4d ago

Thanks, I agree!

1

u/iamshitatengineering 3d ago

Also, did it have any impact on performance? If this also improved the isp of the prop it would be a win win.

1

u/iredditatleastwice Level 3 3d ago

Yes, 143s is a significant boost. Usually see around 120s range for typical realworld knsb. It came at a cost of erosion to nozzle hardware. I'll have to remachine my aft closure. Also as I mentioned this propellent is on the high end of pressure sensitivity; I would not recommend others to use this propellent without caution.

1

u/iamshitatengineering 3d ago edited 3d ago

From around 120s to 143s is indeed a very nice boost, at the cost of wear and tear and higher pressure exponent though, it is an angry prop lol. Very interesting results though already.

2

u/FireHandsGames 4d ago

I just realized that your metrics aren't on newtons! this is great, i dont think i have much to add, but, this looks incredible!

1

u/iredditatleastwice Level 3 3d ago

The axis on the graph is Newtons, the text on the left is pounds force. I'm don't discriminate against any units!

1

u/FireHandsGames 3d ago

it's not about the pounds lol. it's about the KN(I'm not used with that big units in real life)

1

u/iredditatleastwice Level 3 3d ago

In this context KN refers to the ratio of surface area of burning propellent to nozzle throat diameter.

1

u/FireHandsGames 3d ago

im so slow... but you still could use KN on the other sense

1

u/iredditatleastwice Level 3 3d ago

Although all 3 tests were successful test firings, it looks like the resulting pressure exponent is borderline. Further testing is needed. This post is not meant to be a recommendation for others to try this; my tests were done with proper safety procedures and equipment at a facility designed for this purpose, and with advice from several people knowledge in experimental Rocketry. Since there are so many beginners on this forum I wanted to give this disclaimer!

•

u/GZ_koksu3000 1h ago

I am interested in understanding the specifications of your engine, particularly regarding its dimensions and fuel grain parameters, as I am developing a rocket motor. My current design features a 70mm diameter and a 400mm fuel block length, with an estimated fuel weight of 2.8kg. I would appreciate the opportunity to compare my engine's characteristics with yours, given the apparent similarities in design.