Hybrid Gas Generator Applied Research Associates (ARA)

Team: Jaron Dowdy, Ryan Erickson, Noah Mandleco, Chase Newton and Madalyn Pullins

Project Description

  • The Department of Defense and Missile Defense Agency are pursuing a class of vehicles capable of sustained hypersonic atmospheric flight
  • The purpose of this project is to design, build, and test a hybrid gas generator system as a low-cost option for high enthalpy testing
  • The system must simulate high enthalpy, pressure, and temperature conditions of hypersonic flight in the stratosphere (above 80,000 ft)
Parameter Target Threshold Actual
Mach Number 10 3 8.3*
Stagnation Pressure (psi) 50 20 17.5
Stagnation Temperature (K) 2500 1450 1800
Plume Geometry 2D, uniform 2D, nonuniform 2D, uniform

Design Description

Design Description. Labels (top to bottom). Injector Assembly, Fuel Grain Assembly, Motor Casing, Threaded Rod, Seal Ring, Copper Nozzle, Heat Exchanger Assembly
Design Description. Diagram 2

Performance Review

Under-Expanded Plume

Under-Expanded Plume

Perfectly Expanded Plume

Perfectly Expanded Plume

  • Initial tests featured a bifurcated, under-expanded plume
  • Computational fluid dynamics (CFD) and additional analysis was done to diagnose the flow issue and update the design
  • Subsequent tests featured a perfectly expanded, uniform, 2D plume
Test Stand. Wedge Shaped Test Article, Flow Direction, Pressur Transducer and Fiber Optical Cable Ports
  • The test article was introduced and used to measure stagnation pressure and temperature at the leading edge
  • This data is used to confirm the 2D uniformity of the plume, ensure that the system meets client requirements, and define the system’s operating range
Pressure diameters diagram

Conclusion

Conclusion graph 1
Conclusion graph 2
  • Though reaching temperature and enthalpy equivalent Mach number, this facility currently does not reproduce hypersonic flow at the test article
  • However, the facility does produce a 2D, uniform plume and may provide a useful partial analog

Future Work

  • The team learned the importance of material science knowledge, safety consideration and hazard mitigation, and thorough test planning when working with novel technologies
  • Moving forward, the team will hand the project over to the PRL
  • The PRL will continue developing the project, introducing:
    • Different materials for the test article leading edge
    • Additional instrumentation on the test article for supplemental data collection
    • Nitrogen injection to tailor the properties of the plume

Acknowledgements

  • The team would like to thank Stephen Whitmore, Dave Granica, and students at the Propulsion Research Laboratory for their support and investment in this project :)