Margin considerations in SSTO O_2/H_2 engines

摘要

The recent NASA Access to Space Study examined future Earth-to-Orbit (ETO) transportation needs and fleet alternatives out to 2030. The baseline in the Option 3 assessment was a Single-Stage-to-Orbit (SSTO) vehicle. A study was conducted to assess the use of new, advanced, O_2/H_2 engines for the SSTO application. The study defined baseline configurations and ground rules and defined six engine cycles to explore engine performance. The performance in the SSTO mission was then modeled using the resulting engine weights and specific impulse performance and the Access to Space Option 3 vehicle. The effects of turbine operating temperatures and of increased design margins were examined to provide superior life margin and reduction of associated development and operational issues. The results showed that new O_2/H_2 engines are viable and competitive candidates for the SSTO application using chamber pressures of 4,000 psi and turbine operating temperatures well below current engines.