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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 127 records · Page 7

Multi-mission nuclear electric propulsion stage design.

Results of a mission engineering analysis of nuclear-thermionic electric propulsion spacecraft for unmanned interplanetary and geocentric missions. Critical technologies assessed are associated with the development of nuclear electric propulsion (NEP), and the impact of its availability on future space programs. Specific areas of investigation include outer planet and comet rendezvous mission analysis, NEP stage design for geocentric and interplanetary missions, and technology requirements for NEP stage development. A multimission NEP stage can be developed to perform both multiple geocentric and interplanetary missions for a 1983 launch. Identified pacing NEP technology requirements are the development of 20,000 full power hour ion thrustors and thermionic reactor and the development of related power conditioning. The resulting NEP stage design provides both inherent reliability and high payload mass capability.

Prickett, W. Z.↗

A review of nuclear electric propulsion spacecraft system concepts

The last 25-30 years of system concepts and design philosophies for spacecraft employing nuclear-electric propulsion (NEP) are reviewed. NEP spacecraft-system design constraints and criteria are identified, including radiation exposure of humans and electronics, thermal control requirements, effluent contamination of spacecraft surfaces, surface erosion, launch-vehicle integration, operations and safety requirements, attitude control, EM interference, and power control and distribution. The impact on spacecraft design philosophy of these constraints and criteria is explored. Several NEP spacecraft are characterized and discussed with respect to the propulsion system used. The electric propulsion system catagories are electrothermal (arcjet), EM (magnetoplasmadynamic and pulsed-inductive thruster) and electrostatic (ion engine). A brief summary of the mission, nuclear power source, electric propulsion system, and spacecraft configuration are provided for each NEP spacecraft concept.

Deininger, W. D.↗

Multimission nuclear electric propulsion system for outer planet exploration missions

The conceptual design configuration of a nuclear electric propulsion system (NEP) with a multimission capability for both earth orbital and electric propulsion missions is discussed. Two basic types of space reactor power system concepts are analyzed emphasizing conduction coupled and radiation coupled systems, and a radiation coupled thermoelectric panel concept is schematically represented and described in detail. A nuclear-powered 100-kWe surveillance spacecraft concept is presented and the developmental phases are given including cost estimates. In addition, a system is described that seems to have the capability to perform all the outer planet missions.

Mondt, J. F.↗

Design and performance of an arcjet nuclear electric propulsion system for a mid-1990's reference mission

The design and performance of an arcjet nuclear-electric-propulsion spacecraft, suitable for use in the Space Nuclear Power System (SNPS) reference mission, are outlined. The vehicle design was based on a 30-kW ammonia arcjet system operating at an Isp of 1050 s and an efficiency of 45 percent. The arcjet/gimbal system, power-processing unit, and propellant-feed system are described. A 100-kWe SNPS was assumed, and the spacecraft mass was baselined at 5250 kg (excluding the propellant-feed system). A radiation/arcjet efflux diagnostics package was included in the performance analysis. This spacecraft, assuming a Shuttle launch from KSC, can perform a 50-deg inclination change and reach a final orbit of 35,860 km with a 120-d trip time providing a 4-mo active load for the SNPS. Alternatively, a Titan IV launch would provide a mass margin of 120 kg to a 10,000-km, 58-deg final orbit in 74 d. This spacecraft meets the reference-mission constraint of low developmental risk, and is scalable to power levels projected for future space platforms.

Deininger, William D.↗

Optimize out-of-core thermionic energy conversion for nuclear electric propulsion

Current designs for out of core thermionic energy conversion (TEC) to power nuclear electric propulsion (NEP) were evaluated. Approaches to improve out of core TEC are emphasized and probabilities for success are indicated. TEC gains are available with higher emitter temperatures and greater power densities. Good potentialities for accommodating external high temperature, high power density TEC with heat pipe cooled reactors exist.

Morris, J. F.↗

Multi-reactor power system configurations for multimegawatt nuclear electric propulsion

A modular, multi-reactor power system and vehicle configuration for piloted nuclear electric propulsion (NEP) missions to Mars is presented. Such a design could provide enhanced system and mission reliability, allowing a comfortable safety margin for early manned flights, and would allow a range of piloted and cargo missions to be performed with a single power system design. Early use of common power modules for cargo missions would also provide progressive flight experience and validation of standardized systems for use in later piloted applications. System and mission analysis are presented to compare single and multi-reactor configurations for piloted Mars missions. A conceptual design for the Hydra modular multi-reactor NEP vehicle is presented.

George, Jeffrey A.↗

Planetary mission opportunities with nuclear electric propulsion

An assessment is made of the applicability, benefits, and requirements of nuclear-electric propulsion (NEP) for solar system-exploration missions, within the framework of SP-100 reactor-based power technologies and 30-cm ring-cusp thruster technology. An initial launch date of 2005 is projected from a program-inception date of 2000. The missions in question encompass orbitings and flybys of Pluto, accomplishing in 10-13 years which would ballistically require a transfer time of 40 years; a Neptune orbiting; a Jupiter grand tour which will orbit each of the moons in turn; a Uranus orbiting; and a multiple mainbelt asteroid rendezvous orbiting six selected asteroids.

Kelley, James H.↗

Power Conditioning System Modelling for Nuclear Electric Propulsion

NASA LeRC is currently developing a Fortran based model of a complete nuclear electric propulsion (NEP) vehicle that would be used for piloted and cargo missions to the Moon or Mars. The proposed vehicle design will use either a Brayton or K-Rankine power conversion cycle to drive a turbine coupled with a rotary alternator. Two thruster types are also being studied, ion and magnetoplasmadynamic (MPD). In support of this NEP model, Rocketdyne developed a power management and distribution (PMAD) subroutine that provides parametric outputs for selected alternator operating voltages and frequencies, thruster types, system power levels, and electronics coldplate temperatures. The end-to-end PMAD model described is based on the direct use of the alternator voltage and frequency for transmitting power to either ion or MPD thrusters. This low frequency transmission approach was compared with dc and high frequency ac designs, and determined to have the lowest mass, highest efficiency, highest reliability and lowest development costs. While its power quality is not as good as that provided by a high frequency system, it was considered adequate for both ion and MPD engine applications. The low frequency architecture will be used as the reference in future NEP PMAD studies.

Metcalf, Kenneth J.↗

Scoping Calculations of Power Sources for Nuclear Electric Propulsion

This technical memorandum describes models and calculational procedures to fully characterize the nuclear island of power sources for nuclear electric propulsion. Two computer codes were written: one for the gas-cooled NERVA derivative reactor and the other for liquid metal-cooled fuel pin reactors. These codes are going to be interfaced by NASA with the balance of plant in order to make scoping calculations for mission analysis.

Difilippo, F. C.↗

Blazing the trailway: Nuclear electric propulsion and its technology program plans

An overview is given of the plans for a program in nuclear electric propulsion (NEP) technology for space applications being considered by NASA, DOE, and DOD. Possible missions using NEP are examined, and NEP technology plans are addressed regarding concept development, systems engineering, nuclear fuels, power conversion, thermal management, power management and distribution, electric thrusters, facilities, and issues related to safety and environment. The programmatic characteristics are considered.

Doherty, Michael P.↗

Blazing the trailway - Nuclear electric propulsion and its technology program plans

An overview is given of the plans for a program in nuclear electric propulsion (NEP) technology for outer space applications being considered by NASA, DOE, and DOD. Possible missions using NEP are examined, and NEP technology plans are addressed regarding concept development, systems engineering, nuclear fuels, power conversion, thermal management, power management and distribution, electric thrusters, facilities, and issues related to safety and environment. The programmatic characteristics are considered.

Doherty, Michael P.↗

Nuclear Electric Propulsion Technology Panel findings and recommendations

Summarized are the findings and recommendations of a triagency (NASA/DOE/DOD) panel on Nuclear Electric Propulsion (NEP) Technology. NEP has been identified as a candidate nuclear propulsion technology for exploration of the Moon and Mars as part of the Space Exploration Initiative (SEI). The findings are stated in areas of system and subsystem considerations, technology readiness, and ground test facilities. Recommendations made by the panel are summarized concerning: (1) existing space nuclear power and propulsion programs, and (2) the proposed multiagency NEP technology development program.

Doherty, Michael P.↗

Nuclear electric propulsion systems overview

The topics are presented in viewgraph form and include the following: nuclear propulsion background; schedule for the nuclear electric propulsion (NEP) project; NEP for the Space Exploration Initiative; NEP on-going systems tasks; 20KWe mission/system study; and agenda.

Doherty, Michael P.↗