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Solar Thermal Propulsion IHPRPT Demonstration Program

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Spacecraft powered by solar thermal propulsion engines will be able to provide the velocity change required to economically maneuver large payloads from one orbit to another or to perform interplanetary missions. This innovative concept, when applied, will double the efficiency of currently used LH2-L02 chemical upper stages. Solar thermal propulsion uses the suns energy to heat a low molecular-weight working fluid such as hydrogen to very high temperatures 3,000 K. The stored thermal energy is then converted to kinetic energy as the working fluid exits a diverging nozzle. Under funding from the Integrated High Payoff Rocket Propulsion Technology IHPRPT program, the Air Force Research Laboratory AFRL at Edwards AFB, CA, has sponsored the team of Thiokol Propulsion and SRS Technologies to demonstrate the technological readiness and performance of an inflatable solar thermal propulsion system. This paper will address the current status of this program, which includes the following accomplishments 1 component trade studies completed for struts, torus, and lenticular 2 rapid prototyping and hardware-in-the-loop system installed and verified 3 inflation control system designed, fabricated, and tested in both ambient and space environments 4 integrated system fabricated and deployed in space environment 5 sun sensors for focus control system fabricated and tested 6 conceptual design and 3-D dynamic model made of focus control system and 7 modal testing of inflatable concentrator completed in ambient conditions. The program will culminate in a full-up integrated proof-of-concept ground test. This will demonstrate that the technology is ready for development of the flight hardware for the AFRL Solar Orbital Transfer Vehicle SOTV program.

Subject Categories:

  • Thermodynamics
  • Combustion and Ignition
  • Liquid Propellant Rocket Engines
  • Astronautics

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