Evaluation of an Ejector Ramjet Based Propulsion System for Air-Breathing Hypersonic Flight

Scott R Thomas; H Douglas Perkins; Charles J Trefny

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NASA NTRS · 19980018678

Evaluation of an Ejector Ramjet Based Propulsion System for Air-Breathing Hypersonic Flight

Scott R Thomas·H Douglas Perkins·Charles J Trefny

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Abstract

A Rocket Based Combined Cycle (RBCC) engine system is designed to combine the high thrust to weight ratio of a rocket along with the high specific impulse of a ramjet in a single, integrated propulsion system. This integrated, combined cycle propulsion system is designed to provide higher vehicle performance than that achievable with a separate rocket and ramjet. The RBCC engine system studied in the current program is the Aerojet strutjet engine concept, which is being developed jointly by a government-industry team as part of the Air Force HyTech program pre-PRDA activity. The strutjet is an ejector-ramjet engine in which small rocket chambers are embedded into the trailing edges of the inlet compression struts. The engine operates as an ejector-ramjet from takeoff to slightly above Mach 3. Above Mach 3 the engine operates as a ramjet and transitions to a scramjet at high Mach numbers. For space launch applications the rockets would be re-ignited at a Mach number or altitude beyond which air-breathing propulsion alone becomes impractical. The focus of the present study is to develop and demonstrate a strutjet flowpath using hydrocarbon fuel at up to Mach 7 conditions.

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Scott R Thomas, H Douglas Perkins, Charles J Trefny. 1997-12-01. Evaluation of an Ejector Ramjet Based Propulsion System for Air-Breathing Hypersonic Flight. https://ntrs.nasa.gov/citations/19980018678

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