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Propulsion

Explore propulsion reports from NASA NTRS and DOE OSTI. Search rocket engines, electric propulsion and thrusters; verify designs and performance in the source documents.

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At least 937 records · Page 52

All sources NASA NTRS DOE OSTI

NASA NTRS1974

Measurements and calculations of detonation propulsion performance in helium

Previously obtained results are extended to helium ambient gas to help in the assessment of performance in the atmospheres of the major planets. Measurements confirm benefits derived form detonating propellant over conventional chemical rocket propulsion. Benefits however, are reduced at high pressures in low molecular weight gas. Numerical calculations by means of a monodimensional hydrodynamic code follow the different trends obtained experimentally for high and low molecular weight gas and also offer new insights on the time behavior of the process.

Kim, K.↗

NASA NTRS1975

Linear rocket engines for advanced space transportation systems

The linear rocket engine is shown to be a viable candidate propulsion system for post-Space Shuttle single-stage-to-orbit systems. The linear engine system has been developed and fired demonstrating high performance and long life with firing durations exceeding 500 seconds. The application of the split or dual combustor to the linear engine permits the uses of two different propellant combinations in a single engine system. The split combustor possesses the advantages of the two position extendible bell nozzle in a fixed nozzle configuration. Engine power cycles and applications to typical vehicles are discussed.

Sobin, A. J.↗

NASA NTRS1977

A candidate mission using the Shuttle and solar electric propulsion

It is suggested that an out-of-the-ecliptic solar electric propulsion (SEP) mission be performed. Data would be gathered pertaining to the three-dimensional structure of solar features at radio and X-ray wavelengths, the properties of the solar wind as a function of latitude and time, the configuration of the interplanetary field and its relation to solar fields, and the modulations of cosmic rays to determine the spectrum of interstellar cosmic rays. The mission would also, it is thought, demonstrate the capability of SEP for use in Shuttle missions. The SEP spacecraft and the ongoing development of related systems are examined. The weight of a SEP stage is contrasted with the weight of a chemical rocket stage.

Duxbury, J. H.↗

NASA NTRS1977

An evaluation of composite propulsion for single-stage-to-orbit vehicles designed for horizontal take-off

Composite propulsion was analyzed for single-stage-to-orbit vehicles designed for horizontal take-off. Trajectory, geometric, and mass analyses were performed to establish the orbital payload capability of six engines. The results indicated that none of the engines performed adequately to deliver payloads to orbit as analyzed. The single-stage turbine and oxidizer-rich gas generator resulted in a low engine specific impulse, and the performance increment of the ejector subsystem was less than that of a separate rocket system with a high combustion pressure. There was a benefit from incorporating a fan into the engine, and removal of the fan from the airstream during the ramjet mode increased the orbital payload capability.

Martin, J. A.↗

NASA NTRS1979

Propulsion-free separation and rendezvous of small shuttle free-flyers using controlled differential drag

A natural successor in the Shuttle era to many sounding rocket flights is the free-flyer mode of operation, in which the Shuttle Orbiter releases a subsatellite (with payloads), effects a desired separation, and approaches and retrieves the free-layer. The propulsive maneuvers required of the Orbiter by equivalent relative motions obtained through controlled differential drag (via changes in free-layer effective area and/or Orbiter attitude changes) are replaced. Simplified analytical techniques are developed and feasibility is verified.

King, J. C.↗

NASA NTRS1979

A detached experiment carrier aids adaptation of experiments from sounding rockets to Space Shuttle

The detached experiment carrier (DEC) system aids the adaptation of small, low-weight experiments to Space Shuttle missions. The carrier system consists of the detached experiment carrier (free-flyer), a command station at the Orbiter aft station, and a flight support station in the Orbiter payload bay. The carrier is a compact vehicle that is radio controlled by the Shuttle crew. It uses control television, command, and cold gas propulsion systems to deploy experiments from and later rendezvous with the Orbiter. The carrier propulsion system also maintains the attitude control required during experiment execution. Results of engineering investigation, analysis, component design and development, and testing indicate that the DEC system concept is practical. Results of preliminary engineering investigations, including maneuvering system handling qualities and television/telemetry display formats, indicate that the concept of flying the DEC 'out of' and 'into' the Orbiter payload bay is both safe and practical for small, compact free-flyer deployment and retrieval. This paper describes the carrier system, its operations, and potential applications.

Ritz, W. F.↗

NASA NTRS1979

Propulsion-free separation and rendezvous of small Shuttle free-flyers using controlled differential drag

A natural successor in the Shuttle era to many sounding rocket flights is the free-flyer mode of operation, in which the Shuttle Orbiter releases a subsatellite (with payload), effects a desired separation, and finally approaches and retrieves the free-flyer. This paper proposes replacing, to the maximum extent feasible, the propulsive maneuvers required for the Orbiter by equivalent relative motions obtained through controlled differential drag (via changes in free-flyer effective area and/or Orbiter attitude changes). Simplified analytical techniques are developed and feasibility is verified. Several illustrative examples are specified (e.g., a 3-km separation in 1 day, with 4-day return).

King, J. C.↗

NASA NTRS1980

Advanced oxygen-hydrocarbon rocket engine study

Preliminary identification and evaluation of promising liquid oxygen/ hydrocarbon (LO2/HC) rocket engine cycles is reported. A consistent and reliable data base for vehicle optimization and design studies, to demonstrate the significance of propulsion system improvements, and to select the critical technology areas necessary to realize such advances is presented.

Obrien, C. J.↗

NASA NTRS1980

LEO-to-GEO low thrust chemical propulsion

One approach being considered for transporting large space structures from low Earth orbit (LEO) to geosynchronous equatorial orbit (GEO) is the use of low thrust chemical propulsion systems. A variety of chemical rocket engine cycles evaluated for this application for oxygen/hydrogen and oxygen/hydrocarbon propellants (oxygen/methane and oxygen/RF-1) are discussed. These cycles include conventional propellant turbine drives, turboalternator/electric motor pump drive, and fuel cell/electric motor pump drive as well as pressure fed engines. Thrust chamber cooling analysis results are presented for regenerative/radiation and film/radiation cooling.

Shoji, J. M.↗

NASA NTRS1979

Status of Space Shuttle External Tank Solid Rocket Booster and Main Engine

The current status of three major propulsion elements for the Space Transportation System is reviewed: the Space Shuttle Main Engine, the External Tank, and the Solid Rocket Booster. Consideration is given to test and manufacturing experience in the last year, test and manufacturing plans for the coming year, and the current status of the hardware to support the first manned orbital flight.

Lindstrom, R. E.↗

NASA NTRS1981

Electric propulsion - characteristics, applications, and status

A comparative review of the principles of ion thruster and chemical rocket operations is presented. The 30cm mercury ion thruster development and the specifications imposed on it by the Solar Electric propulsion System program are discussed. The 30cm thruster operating range, efficiency, wear out lifetime, and interface requirements are described.

Maloy, J. E.↗

NASA NTRS1981

Advanced oxygen-hydrocarbon rocket engine study

This study identifies and evaluates promising LO2/HC rocket engine cycles, produces a consistent and reliable data base for vehicle optimization and design studies, demonstrates the significance of propulsion system improvements, and selects the critical technology areas necessary to realize an improved surface to orbit transportation system. Parametric LO2/HC engine data were generated over a range of thrust levels from 890 to 6672 kN (200K to 1.5M 1bF) and chamber pressures from 6890 to 34500 kN (1000 to 5000 psia). Engine coolants included RP-1, refined RP-1, LCH4, LC3H8, LO2, and LH2. LO2/RP-1 G.G. cycles were found to be not acceptable for advanced engines. The highest performing LO2/RP-1 staged combustion engine cycle utilizes LO2 as the coolant and incorporates an oxidizer rich preburner. The highest performing cycle for LO2/LCH4 and LO2/LC3H8 utilizes fuel cooling and incorporates both fuel and oxidizer rich preburners. LO2/HC engine cycles permitting the use of a third fluid LH2 coolant and an LH2 rich gas generator provide higher performance at significantly lower pump discharge pressures. The LO2/HC dual throat engine, because of its high altitude performance, delivers the highest payload for the vehicle configuration that was investigated.

Obrien, C. J.↗

NASA NTRS1981

Propulsion system ignition overpressure for the Space Shuttle

Liquid and solid rocket motor propulsion systems create an overpressure wave during ignition, caused by the accelerating gas particles pushing against or displacing the air contained in the launch pad or launch facility and by the afterburning of the fuel-rich gases. This wave behaves as a blast or shock wave characterized by a positive triangular-shaped first pulse and a negative half-sine wave second pulse. The pulse travels up the space vehicle and has the potential of either overloading individual elements or exciting overall vehicle dynamics. The latter effect results from the phasing difference of the wave from one side of the vehicle to the other. This overpressure phasing, or delta P environment, because of its frequency content as well as amplitude, becomes a design driver for certain panels (e.g., thermal shields) and payloads for the Space Shuttle. The history of overpressure effects on the Space Shuttle, the basic overpressure phenomenon, Space Shuttle overpressure environment, scale model overpressure testing, and techniques for suppressing the overpressure environments are considered.

Ryan, R. S.↗

NASA NTRS1983

Radiation energy receiver for laser and solar propulsion systems

The concept of remotely heating a rocket propellant with a high intensity radiant energy flux is especially attractive due to its high specific impulse and large payload mass capabilities. In this paper, a radiation receiver-thruster which is especially suited to the particular thermodynamic and spectral characteristics of highly concentrated solar energy is proposed. In this receiver, radiant energy is volumetrically absorbed within a hydrogen gas seeded with alkali metal vapors. The alkali atoms and molecules absorb the radiant flux and, subsequently, transfer their internal excitation to hydrogen molecules through collisional quenching. It is shown that such a radiation receiver would outperform a blackbody cavity type receiver in both efficiency and maximum operating temperatures. A solar rocket equipped with such a receiver-thruster would deliver thrusts of several hundred newtons at a specific impulse of 1000 seconds.

Rault, D. F. G.↗

NASA NTRS1985

Composite Loads Spectra for Select Space Propulsion Structural Components

Rocket engine technology continues to demand higher performance with lighter weight components that have man-rated reliability requirements. These requirements have yielded higher operating pressures, temperatures, and transient effects as well as markedly increased mechanical vibration and flow-related loads. The difficulty in installation, cost, and potential for destroying an engine severely limited the required instrumentation and measurements to adequately define loads of key components such as turbine blades. Also, accurate analytical methodologies for defining internal flow-related loads are just emerging for problems typically found in rocket engines. The difficulty of obtained measured data and verified analysis methodologies has led to the probabilistic load definition approach.

Newell, J. F.↗

NASA NTRS1984

Lox/hydrocarbon propellants for space propulsion systems

The significant results of technology efforts directed by the NASA Lyndon B. Johnson Space Center investigating liquid oxygen/hydrocarbon (lox/HC) propellant combination are presented. These efforts are intended to identify viable propellant combinations and system designs to replace nitrogen tetroxide and monomethylhydrazine for future spacecraft orbital maneuvering and attitude control systems, and to date have been focused primarily on the various technology areas of lox/HC combustion - injector element design effects, performance, combustion chamber heat transfer, coking, and ignition. In addition, a study was performed to compare candidate lox/HC propulsion system concepts and to evaluate major system/component design options. The data generated provide quantitative substantiation of trends previously experienced with hypergolic propellants and with a lox and rocket propellant combination. More importantly, however, the data provide a sound footing for the technology data base that must be built to support future systems development.

Boyd, W. C.↗

NASA NTRS1986

Structural integrity and durability for Space Shuttle main engine and future reusable space propulsion systems

NASA is conducting a program which will establish a technology base for the orderly evolution of reusable space propulsion systems. As part of that program, NASA initiated a Structural Integrity and Durability effort for advanced high-pressure oxygen-hydrogen rocket engine technology. That effort focuses on the development of: (1) accurate analytical models to describe flow fields; aerothermodynamic loads; structural responses; and fatigue/fracture, from which life prediction codes can be evolved; and (2) advanced instrumentation with capabilities to verify the codes in an SSME-like environment as well as the potential for future use as diagnostic sensors for real-time condition monitoring of critical engine components.

Marsik, S. J.↗

NASA NTRS1986

Heat transfer in space power and propulsion systems

NASA's planned Space Station has projected power requirements in the 75-300 kW range; attention is presently given to the range of power system configurations thus far proposed. These are a silicon solar cell system incorporating regenerative fuel cell or battery storage, with a 10-year lifetime, a solar-dynamic power system with phase-change or regenerative fuel cell energy storage, and a combination of these two alternatives. A development status evaluation is also given for the propulsion systems that may be used by next-generation boosters. These include such novel airbreathing systems as turboramjets, air liquefaction cycle rockets, airturboramjet/rockets, and supersonic combustion ramjets.

Hendricks, R. C.↗