Responsible Engineers: Ellie, Abraheim, Trevor, Jorian, Tamara, Berkin, Elizabeth
3/4 Assignments
Trevor - stealing ellie's stuff
Ellie - plasticizer and bonding agents and other liquids (how to get more burn out of it), look into GAP
Abraheim - nail down breakdown of solids packing ratio for aluminum and AP, find suppliers for all types of AP, do solids packing calcs
Tamara - look into combustion simulation
Jorian - nail down percentages of aluminum boride, find suppliers
Berkin - look into ADN and GAP, look into burn rate suppressants
Lee - magnesium boride
Simulation update:
- NASA Software requires higher level access, self verification with social security number. (Thoughts?)
- Emailed Zolti for suggestions, no response yet
- Flow 3D could be viable, has free academic license but needs to be installed department wide- possibly negotiable over email though.
- Propep (used before)
- There are combustion temperature equations that we could theoretically code but that's a lot of work.
Improvements We Want from Angry Goat
- higher isp (Angry goat had 200-210 isp)
- increased efficiency
- burn closer to surface of propellant
Erosive burning
- higher throat entrance to throat area ratio
Solids packing
- 4-6-1
- 400, 90 micron AP, 3 micron Al
- Most use aggregate of aluminum sizes ranging between 3 micron and 40 micron
Things to look into:
- energetic plasticizer
- different combinations of binders, curative and plasticizer
- combined HTPB and Tepanol https://www.rocketmotorparts.com/Hydroxyl-terminated_Polybutadiene_Resin_wCAO-5_Antioxidant___HX-752_Bonding_Agent_1_Gallon/p1577809_20282764.aspx
- RPA for simulating propellant properties
Notes on fuel and additives to fix slag issues
- Lithium (hella toxic and expensive) and boron have the best combustion temperatures (gravimetrically)
- Boron has high efficiency but it requires high heat of combustion and it is easily oxidized so a boron oxide film forms around the boron atoms and prevents diffusion of oxygen during combustion. (would probably need more oxidizer and decrease the amount of aluminum and boron/magnesium)
- Most articles talk specifically about boron and just say it suppresses the burning of the aluminum, need to look into more literature about aluminum diborate https://arc.aiaa.org/doi/pdf/10.2514/3.26212
- Instead use metal borides
- Aluminum Diborate (around 1-6 microns)
- 121.5 J/cc (volumetric)
- 37.5 kJ/g
- Decreases ignition delay by a factor of 1.5-2
- Described on page 8 ENERGETICMATERIALSANDMETALBORIDESFORSOLIDPROPELLANTROCKETENGINES819441-1374197.pdf
- longer burn time than aluminum-boron mixture (what we are looking for), longer ignition delay (need stronger hei) (source: https://www.sciencedirect.com/science/article/pii/S1270963818322673)
- Magnesium diborate
- https://collections.lib.utah.edu/details?id=195697 - thermodynamic comparisons of a number of metal borides including magnesium and aluminum diboride
- Aluminum Diborate (around 1-6 microns)
- Large boron particles increase linear burn rate (makes the combustion occur closer to the surface of the propellant) https://link.springer.com/article/10.1134/S0010508222050136(make someone read this because it has a lot of formulas about sims so maybe make someone make a sim)
- Also increases temperature
- Boron has high efficiency but it requires high heat of combustion and it is easily oxidized so a boron oxide film forms around the boron atoms and prevents diffusion of oxygen during combustion. (would probably need more oxidizer and decrease the amount of aluminum and boron/magnesium)
- Magnesium
- Increases heat of combustion but is much more toxic
- And much more reactive (apparently can react just with water and explode. Not good)