This project took place in spring 2019 as part of OSU’s first rocket propulsion course. 2 teams worked on developing potassium nitrate-sorbitol (KNSB) solid propellant rocket motors and a 3D-printed, water-cooled rocket nozzle for said KNSB motors. I managed both teams throughout the semester making sure we stuck to deadlines and weren’t relying on one team or the other for progress. We wrote papers for both projects and presented them at AIAA SciTech 2020.
The presentation slides I gave at SciTech are linked here for download, and I made a blog post about the conference here. This is the link to the paper itself but requires payment to read. I discuss the following in the presentation:
1. Motivation behind this project (aimed at small satellite-scale thrust chambers to reduce cost from expensive refractory metal alloys)
2. Our nozzle design considerations due to 3D printing, such as overhang angle and support material,
3. The motor test bed and test stand to simulate high-pressure, high-temperature environments
4. Final nozzle design
5. Nozzle ablation data and results (plastic is not a good 3D printing material, shocking, I know)
6. Hotfire data
7. Preliminary CFD that validated some of the cold-flow water testing of the nozzles.
The presentation contains GIFs of the hotfire videos if that’s of interest.
This project as a whole was super progressive for making research motors at OSU. I learned to use a late to make closures, we 3D printed a bunch of nozzles, safely mixed and cast solid propellant grains, and I got a bunch of experience making KNSB propellant the summer following the project, even launching OSU’s first research motors in summer 2019.