Advancements in Hybrid Rocket Design for Space Exploration

1. Project M.E.T.E.O.R. P07109: Flying Rocket Team Andrew Scarlata, Geoff Cassell, Zack Mott, Garett Pickett, Brian Whitbeck, Luke Cadin, David Hall

2. M.E.T.E.OS.R. Overview • Immediate goal is to prove ability to launch a hybrid rocket using Nitrous Oxide and HTPB carrying a small payload to the boundary of space. • Long-term goal is to launch payloads both into space and to land them on NEO’s. • Meteor rocket is carried to altitude by weather balloons, released, and propels itself into orbit.

3. Our Objectives • Responsible for integration of Steel Rocket and Guidance teams’ systems. • Optimized Fuel Grain, Combustion chamber, Nozzle and Injector designs. • Thrust Vectoring and guidance systems. • Research materials that satisfy the design requirements. • Design, Manufacture, Test and Launch Single Stage Rocket • Research shows that successful rockets adhere to a 1:10 structure to propellant ratio. The minimum requirement is 2:10.

4. Rocket Design Concepts Hot means Owwie! • Five designs • Classic • Chalice • Embedded Fuel Grain • Exterior Nitrous Oxide Tanks • Annular Nitrous Oxide Tank

5. Classic Concept • Constant radius dimensions determined by Fuel Grain • Advantages • Easy to manufacture • All subsystems can be contained within outer shell • Disadvantages • Extreme length requires excess weight • Guarantees custom Nitrous Tank

6. Micro IMU (Inertial Measurement Unit) Payload Electronics Helium Reservoir Composite Outer Shell (Possibly Aluminum Reinforced) Nitrous Oxide Tank Pre-Combustion Chamber HTPB Fuel Grain Post-Combustion Chamber Graphite Nozzle

7. Payload Pico-Satellite Micro IMU Provides serial digital outputs of tri-axial acceleration, rate of turn (gyro) and tri-axial magnetic field data. Electronics Avionics and Data Acquisition Helium Reservoir

8. Nitrous Oxide Tank (Liquid Fuel) Pre-Combustion Chamber Moldable Ceramic, acts also as an insulator for the composite shell HTPB Fuel Grain (Solid Fuel)

9. HTPB Fuel Grain (Solid Fuel) Post-Combustion Chamber Moldable Ceramic, acts also as an insulator for the composite shell Graphite Nozzle Currently replicates the steel rocket design

10. Chalice Concept • Dimensions determined by Nitrous Tank • Advantages • Reduced weight due to aspect ratio and variable radius • All subsystems contained within shell • Accommodates varied payload geometries • Potential for off the shelf Nitrous tank • Disadvantages • Complex geometries complicate production

11. Micro IMU (Inertial Measurement Unit) Payload Electronics Helium Reservoir Composite Outer Shell (Aluminum Inner Reinforced) Nitrous Oxide Tank Pre-Combustion Chamber HTPB Fuel Grain Post-Combustion Chamber Graphite Nozzle

12. Micro IMU Payload Pico-Satellite Electronics Avionics and Data Acquisition Helium Reservoir

13. Nitrous Oxide Tank (Liquid Fuel) Pre-Combustion Chamber Combustor HTPB Fuel Grain (Solid Fuel)

14. HTPB Fuel Grain (Solid Fuel) Post-Combustion Chamber Graphite Nozzle – Replicates the steel rocket design

15. Embedded Fuel Grain • Dimensions determined by nitrous tank • Advantages • Reduced Pressure Differential surrounding fuel grain • Single tank forms main body surrounding engine assembly on all but nozzle side • Disadvantages • Complex structural design

16. Micro IMU (Inertial Measurement Unit) Payload Helium Reservoir Vessel Electronics Nitrous Oxide Tank Pre-Combustion Chamber Composite Outer Shell (Aluminum Inner Liner) Siphon Tube HTPB Fuel Grain Post-Combustion Chamber Graphite Nozzle

17. Micro IMU Payload Pico-Satellite Electronics Avionics and Data Acquisition Helium Reservoir

18. Nitrous Oxide Tank (Liquid Fuel) Pre-Combustion Chamber HTPB Fuel Grain (Solid Fuel)

19. Siphon Tube HTPB Fuel Grain (Solid Fuel) Post-CombustionChamber Graphite Nozzle Steel rocket replica

20. Other Concepts • External Nitrous Tanks • Four External tanks mount outside of main body, providing more compact rocket, but added cost. • Annular Nitrous Tank • Single tank mounts around main body, providing more structural strength but added weight and cost.

22. Material Concepts • Researched metal, ceramic and fibrous and honeycomb composite possibilities • Metals and ceramics are cheap, easy to manufacture, however are too heavy for this application by themselves. • Composites may not hold up to heat, pressure and acceleration stresses. • Solution may be hybrid: composite overwound aluminum.

23. Nitrous Oxide: Self Pressurization • Rely on self pressurizing characteristics of Nitrous Oxide(N20) to drive liquid N20 flow • Vapor pressure a very strong function of temperature • Atmospheric temperatures during balloon ascent as low as -57 degrees Celsius, will cool N20 • Clear need to carefully regulate temperature pressure, likely target range between 20 and 30 Celsius (734 to 916 psi).

24. Self Pressurization • Furthermore, critical temperature of N20 is 36.42 Celsius; past the critical point, most thrust will be lost • Would need to develop accurate heat transfer model to insure tank would be kept at proper temperature • Insulation and heater will be required

25. Helium Gas Pressurization • Would use separate tank of Helium at high pressure (regulated to desired pressure) to pressurize N20 tank • Helium pressure will be much less temperature sensitive and will be able to supply pressure reliably that we need • Provide constant pressure (and hence thrust) throughout entire burn time • Will add weight to system, which is at a premium

26. Schedule for rest of SD1 Hot means Owwie! Week 6: Intense revision of concept for final selection, further material research/selection, further modeling of concept. Week 7: Start basic system design, begin risk and engineering analysis, continued modeling of design. Week 8: Continue FEA analysis, complete proof of concept, begin material purchasing, complete design modeling. Week 9: Completion of basic system design, prepare for Design Review, continue material purchasing. Week 10: Plan for SD2, continuation of system design, material purchasing.

27. Questions? Thank You