382
382
Jul 11, 2010
07/10
by
PLATZ, R
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SOME EARLY ATTEMPTS TO CONSTRUCT SAIL PLANES ARE REPORTED. THE AUTHORS ARE EXAMINING SOME NEW DESIGNS AND NEW CONCEPTS FOR THE FLIGHT CONTROL OF SUCH CRAFT. THEY NOTE THAT THE PROSPECTS FOR THE CONSTRUCTION OF A LIGHT WEIGHT, DURABLE, EASILY DISASSEMBLED PLANE OF THIS TYPE ARE GOOD.
Topics: COMETS, NUCLEAR ELECTRIC PROPULSION, SPACE EXPLORATION, ION ENGINES, SPACECRAFT DESIGN
421
421
May 31, 2011
05/11
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Newquist, Charles W.; Verzemnieks, Juris; Keller, Peter C.; Rorabaugh, Michael; Shorey, Mar
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This program addresses the development of high temperature structural seals for control surfaces for a new generation of small reusable launch vehicles. Successful development will contribute significantly to the mission goal of reducing launch cost for small, 200 to 300 pound payloads. Development of high temperature seals is mission enabling. For instance, ineffective control surface seals can result in high temperature (3100 F) flows in the elevon area exceeding structural material limits....
Topics: THERMAL PLASMAS, ION INJECTION, PULSED PLASMA THRUSTERS, METALLIC PLASMAS, DESIGN ANALYSIS,...
293
293
Jun 21, 2010
06/10
by
NON
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eye 293
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Telemetry simulations, radar equipment and experiments, and related supporting research for Deep Space Network
Topics: NUCLEAR ELECTRIC PROPULSION, SPACECRAFT DESIGN, UNMANNED SPACECRAFT, COMPUTER PROGRAMMING, LAUNCH...
232
232
Jun 1, 2011
06/11
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Nixon, Mark W.; Langston, Chester W.; Singleton, Jeffrey D.; Piatak, David J.; Kvaternik, Raymond G.; Corso, Lawrence M.; Brown, Ros
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A new four-bladed, semi-articulated, soft-inplane rotor system, designed as a candidate for future heavy-lift rotorcraft, was tested at model scale on the Wing and Rotor Aeroelastic Testing System (WRATS), a 1/5-size aeroelastic wind-tunnel model based on the V-22. The experimental investigation included a hover test with the model in helicopter mode subject to ground resonance conditions, and a forward flight test with the model in airplane mode subject to whirl-flutter conditions. An active...
Topics: EARTH ORBITS, REUSABLE ROCKET ENGINES, REUSABLE SPACECRAFT, REUSABLE LAUNCH VEHICLES, CRYOGENIC...
256
256
Jul 11, 2010
07/10
by
LEBLANC, G
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eye 256
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DISTANCE PREDICTING METHODS FOR AIRCRAFT BRAKING PERFORMANCE IS DISCUSSED FOR THE CASE WHEN BRAKING IS NOT LIMITED BY THE BRAKES, BUT BY THE CHARACTERISTICS OF TIRE-RUNWAY CONTACT. RECENTLY DEVELOPED FIGHTER AND LARGE CAPACITY TRANSPORT AIRCRAFT REQUIRE THAT STOPPING DISTANCES AND RUNWAY LENGTHS BE ACCURATELY CORRELATED FOR DIFFERENT TOUCHDOWN VELOCITIES, WIND, AND RUNWAY CONDITIONS.
Topics: NUCLEAR ELECTRIC PROPULSION, SPACECRAFT CONFIGURATIONS, PAYLOADS, SPACECRAFT DESIGN, TEMPERATURE...
176
176
Jun 11, 2011
06/11
by
Oreopoulos, Lazaros; Cahalan, Robert F
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Two full months (July 2003 and January 2004) of MODIS Atmosphere Level-3 data from the Terra and Aqua satellites are analyzed in order to characterize the horizontal variability of cloud optical thickness and water path at global scales. Various options to derive cloud variability parameters are discussed. The climatology of cloud inhomogeneity is built by first calculating daily parameter values at spatial scales of l degree x 1 degree, and then at zonal and global scales, followed by...
Topics: NUCLEAR ELECTRIC PROPULSION, SPACECRAFT PROPULSION, SPACECRAFT DESIGN, DESIGN OPTIMIZATION, GENETIC...
176
176
May 31, 2011
05/11
by
Chen, James R.; Mathe, Nathalie; Wolfe, Shaw
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In this paper, we present DIAMS, a system of distributed, collaborative information agents which help users access, collect, organize, and exchange information on the World Wide Web. Personal agents provide their owners dynamic displays of well organized information collections, as well as friendly information management utilities. Personal agents exchange information with one another. They also work with other types of information agents such as matchmakers and knowledge experts to facilitate...
Topics: END-TO-END DATA SYSTEMS, COMPUTERIZED SIMULATION, ENGINE TESTS, NUCLEAR ELECTRIC PROPULSION,...
279
279
Jun 21, 2010
06/10
by
Feiler, C. E.; Heidmann, M. F
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eye 279
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Rocket combustion chamber stability by controlling transverse instability during propellant combustion
Topics: ELECTRONIC EQUIPMENT, INTERPLANETARY SPACECRAFT, RADIATION EFFECTS, DATA REDUCTION, LITERATURE,...
304
304
May 31, 2011
05/11
by
Tumer, Irem Y
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The purpose of health monitoring systems is to detect failures or defects for increased safety and performance and to provide on-condition maintenance with reduced costs. The problems associated with health monitoring systems include high rates of false alarms and missed failures, which make monitoring an unreliable and costly task. The reason for this is that unaccounted variations invalidate signal modeling assumptions. Our approach was to focus on vibration monitoring of rotating components....
Topics: BRAYTON CYCLE, NUCLEAR ELECTRIC POWER GENERATION, NUCLEAR ELECTRIC PROPULSION, ENERGY CONVERSION...
182
182
Sep 20, 2010
09/10
by
Workman, Gary L
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This report covers the activities performed in the Drop Tube Study which The University of Alabama in Huntsville designed, fabricated and performed various low gravity experiments in materials processing from November 1, 1991 through October 30, 1992. During the performance of this contract the utilization of these ground-based containerless processing facilities has been instrumental in providing the opportunity to determine the feasibility of performing a number of solidification experiments...
Topics: BRAYTON CYCLE, NUCLEAR ELECTRIC PROPULSION, NUCLEAR FUELS, REACTOR DESIGN, REACTOR TECHNOLOGY,...
289
289
Jun 2, 2011
06/11
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Ryan, H. M.; Solano, W.; Holland, R.; Saint Cyr, W.; Rahman, S
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Year 2000 has been an active one for rocket propulsion testing at the NASA John C. Stennis Space Center. This paper highlights several major test facilites for large-scale propulsion devices, and summarizes the varied nature of the recent test projects conducted at the Stennis Space Center (SSC) such as the X-33 Aerospike Engine, Ultra Low Cost Engine (ULCE) thrust chamber program, and the Hybrid Sounding Rocket (HYSR) program. Further, an overview of relevant engineering capabilities and...
Topics: NUCLEAR ELECTRIC PROPULSION, SPACECRAFT RADIATORS, HEAT TRANSFER, GANYMEDE, CONVERTERS, ELECTRIC...
387
387
Jun 1, 2011
06/11
by
Valerio, Matthew D.; Romanofsky, Robert R.; VanKeuls, Fred W
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eye 387
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We developed an automated measurement system using a PC running a LabView application, a Velmex BiSlide X-Y positioner, and a HP85l0C network analyzer. The system provides high positioning accuracy and requires no user supervision. After the user inputs the necessary parameters into the LabView application, LabView controls the motor positioning and performs the data acquisition. Current parameters and measured data are shown on the PC display in two 3-D graphs and updated after every data...
Topics: GAS COOLED REACTORS, NICKEL ALLOYS, THERMAL SIMULATION, SPACECRAFT PROPULSION, BRAYTON CYCLE, GAS...
224
224
Jun 13, 2011
06/11
by
NON
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This paper focuses on participation in the MidCiX field campaign, and post-field campaign data processing and archiving.
Topics: NUCLEAR ELECTRIC PROPULSION, LOW EARTH ORBITS, THRUST AUGMENTATION, SPACE MISSIONS, NASA SPACE...
217
217
May 31, 2011
05/11
by
Martin, Lynne; Orasanu, Judith; Villeda, Eri
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One way to enhance the effectiveness of Special Purpose Operational Training' (SPOT) debriefing sessions may be for instructors to make explicit connections between the Crew Resource Management (CRM) concepts a carrier advocates and the behaviors displayed by the crew in question. A tool listing key behaviors from the scenario was devised, accompanied by an instructors' training session in which links were made between the behaviors and the underlying CRM processes they reflect. The aim of the...
Topics: NUCLEAR ELECTRIC PROPULSION, MOLTEN SALTS, REACTOR TECHNOLOGY, PLANETARY SURFACES, LIQUID METALS
213
213
Jun 2, 2011
06/11
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Wignarajah, Kanapathipillai; Pisharody, Suresh; Fisher, John W
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The elemental composition of food consumed by astronauts is well defined. The major elements carbon, hydrogen, oxygen, nitrogen and sulfur are taken up in large amounts and these are often associated with the organic fraction (carbohydrates, proteins, fats etc) of human tissue. On the other hand, a number of the elements are located in the extracellular fluids and can be accounted for in the liquid and solid waste fraction of humans. These elements fall into three major categories - cationic...
Topics: NUCLEAR ELECTRIC PROPULSION, ARCHITECTURE (COMPUTERS), FISSION, SPACECRAFT LAUNCHING, CERMETS,...
243
243
May 21, 2011
05/11
by
Blaisdell, G. A.; Zeman, O
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The dilatational dissipation rate within compressible homogeneous turbulent shear flow is studied using data from direct numerical simulations. It is found that the dilatational dissipation rate is mainly associated with large scale acoustic waves. Eddy shocklets are observed; however, they have little contribution to the average dissipation rate. A mechanism for the generation of eddy shocklets is shown to be the focusing of acoustic waves. Turbulence models for the dilatational dissipation...
Topics: MANNED MARS MISSIONS, NUCLEAR ELECTRIC PROPULSION, NUCLEAR FUELS, REACTOR DESIGN, MIRROR FUSION,...
362
362
Jun 12, 2011
06/11
by
Lawson, Anthony L.; Parthasarathy, Ramkumar N
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eye 362
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It has been observed in previous experimental studies that round helium jets injected into air display a repetitive structure for a long distance, somewhat similar to the buoyancy-induced flickering observed in diffusion flames. In order to investigate the influence of gravity on the near-injector development of the flow, a linear temporal stability analysis of a round helium jet injected into air was performed. The flow was assumed to be isothermal and locally parallel; viscous and diffusive...
Topics: ELECTRIC PROPULSION, NUCLEAR ELECTRIC PROPULSION, CHEMICAL PROPULSION, SOLAR GENERATORS, NUCLEAR...
277
277
May 31, 2011
05/11
by
Qian, Jian-Hua; Tao, Wei-Kuo; Lau, K.-M
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eye 277
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A case of torrential precipitation process in the Mei-yu front, an Asian monsoon system east to the Tibetan Plateau, is studied with the coupled Penn State University/NCAR MM5 and NASA/GSFC PLACE (Parameterization for Land - Atmosphere - Cloud Exchange) models. Remote and local impacts of water vapor on the location and intensity of Mei-yu precipitation are studied by numerical experiments. Results demonstrate that the water vapor source for this heavy precipitation case in Yangtze river basin...
Topics: REACTOR TECHNOLOGY, NUCLEAR ELECTRIC PROPULSION, MOLTEN SALTS, POWER REACTORS, LIQUID METALS, HEAT...
347
347
Jul 23, 2010
07/10
by
Simons, Rainee N.; Bhasin, Kul. B
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eye 347
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Direct current and also the microwave characteristics of optically illuminated AlGaAs/GaAs HEMT are experimentally measured for the first time and compared with that of GaAs MESFET. The results showed that the average increase in the gain is 2.89 dB under 1.7 nW/sq cm optical intensity at 0.83 microns. Further, the effect of illumination on S-parameters is more pronounced when the devices are biased close to pinch off. Novel applications of optically illuminated HEMT as a variable gain...
Topics: CHEMICAL PROPULSION, ORBIT CALCULATION, EXHAUST VELOCITY, ION PROPULSION, MANNED SPACE FLIGHT,...
Space nuclear power systems are considered for use in those particular spacecraft applications for which nuclear power systems offer unique advantages over solar and/or chemical space power systems. Both isotopic and reactor heated space electrical power units are described in an attempt to illustrate their operating characteristics, spacecraft integration aspects, and factory-to-end of mission operational considerations. The status of technology developments in nuclear power systems is...
Topics: NASA Technical Reports Server (NTRS), NUCLEAR ELECTRIC POWER GENERATION, NUCLEAR ELECTRIC...
A nuclear thermionic reactor as the electric power source for an electric propulsion spacecraft introduces a nuclear radiation environment that affects the spacecraft configuration, the use and location of electrical insulators and the science experiments. The spacecraft is conceptually configured to minimize the nuclear shield weight by: (1) a large length to diameter spacecraft; (2) eliminating piping penetrations through the shield; and (3) using the mercury propellant as gamma shield. Since...
Topics: NASA Technical Reports Server (NTRS), ION ENGINES, NUCLEAR ELECTRIC PROPULSION, RADIATION...
Equations and charts are presented that permit rapid estimation of propulsion-system performance requirements for some typical deep-space missions. A number of advanced propulsion concepts for which performance estimates are available are compared with respect to their capability for flyby, rendezvous, and roundtrip planetary missions. Based on these estimates, the gas-core nuclear fission rocket and the pulsed fusion rocket yield the fastest trip times to the near planets. For round trips to...
Topics: NASA Technical Reports Server (NTRS), MISSION PLANNING, PROPULSION SYSTEM CONFIGURATIONS,...
Current analysis of advanced unmanned planetary missions in the 1980's and beyond indicate the need for propulsion systems with performance capabilities beyond those of current and near state-of-art. One propulsion system concept being considered to fill this need is nuclear electric low thrust propulsion (NEP). Two different NEP system power levels are considered for performance analysis: 100 kw and 250 kw. The 100 kw NEP system uses a Centaur(D-1T) chemical stage for injection to an...
Topics: NASA Technical Reports Server (NTRS), INTERPLANETARY SPACECRAFT, NUCLEAR ELECTRIC PROPULSION, OUTER...
A theoretical investigation was conducted to estimate the spectral properties of argon as a function of pressure, temperature, and wave number. The spectral characteristics of the argon buffer gas exert a strong influence on radiative energy transfer in the in-reactor test configuration of the nuclear light bulb engine. An existing computer program was modified and used to calculate the spectral absorption coefficients of argon at total pressures of 50, 100, 250, 500, 750 and 1000 atm in the...
Topics: NASA Technical Reports Server (NTRS), ABSORPTION SPECTRA, ALUMINUM, ARGON, SILICON, SPECTRAL...
The effects of trip time, propulsion time, and specific powerplant mass are studied for optimized unmanned probe spacecraft on missions to Uranus with nuclear-electric propulsion systems. Electric propulsion is confined to a single thrust period at the beginning of each mission. Mission profiles include both high-thrust and electric-propulsion Earth-departure modes for planet flyby and orbital capture. Effects of propulsion time and propulsion system parameters are evaluated, and typical design...
Topics: NASA Technical Reports Server (NTRS), NUCLEAR ELECTRIC PROPULSION, THRUST PROGRAMMING, UNMANNED...
The three advanced propulsion systems analyzed are an advanced chemical system, an improved solid-core nuclear rocket engine with a 25-kilowatt auxiliary powerplant, and a nuclear-electric system. The comparison of these systems is made on the basis of transportation cost divided by the expected value of the data returned to earth. The analysis shows that for the Mercury Orbiter mission and for missions to the outer planets with a high data requirement, the nuclear-electric system emerges as...
Topics: NASA Technical Reports Server (NTRS), CHEMICAL PROPULSION, COST EFFECTIVENESS, MISSION PLANNING,...
A preliminary failure mode, failure effect, and criticality analysis of the major subsystems of nuclear electric propulsion is presented. Simplified reliability block diagrams are also given. A computer program was used to calculate the reliability of the heat rejection subsystem.
Topics: NASA Technical Reports Server (NTRS), NUCLEAR ELECTRIC PROPULSION, RELIABILITY ANALYSIS, COMPUTER...
A preliminary examination is reported of several special ways for space disposal of nuclear waste material which utilize the radioactive heat in the waste to assist in the propulsion for deep space trajectories. These include use of the wastes in a thermoelectric generator (RTG) which operates an electric propulsion device and a radioisotope - thermal thruster which uses hydrogen or ammonia as the propellant. These propulsive devices are compared to the space tug and the space tug/solar...
Topics: NASA Technical Reports Server (NTRS), EXTRATERRESTRIAL ENVIRONMENTS, RADIOACTIVE WASTES,...
The thermionic reactor control system design studies conducted over the past several years for a nuclear electric propulsion system are described and summarized. The relevant reactor control system studies are discussed in qualitative terms, pointing out the significant advantages and disadvantages including the impact that the various control systems would have on the nuclear electric propulsion system design. A recommendation for the reference control system is made, and a program for future...
Topics: NASA Technical Reports Server (NTRS), NUCLEAR ELECTRIC PROPULSION, NUCLEAR REACTOR CONTROL, SYSTEMS...
Conceptual designs of the nuclear propulsion programs are reported. Major areas of investigation were (1) design efforts on spacecraft configuration and heat rejection subsystem, (2) high-voltage thermionic reactor concepts, and (3) dual-mode spacecraft configuration study.
Topics: NASA Technical Reports Server (NTRS), NUCLEAR ELECTRIC PROPULSION, SPACECRAFT CONFIGURATIONS,...
The application of a nuclear electric propulsion (NEP) stage in the exploration of near-earth, cometary, and planetary space was discussed. The NEP stage is powered by a liquid-metal-cooled, fast spectrum thermionic reactor capable of providing 120 kWe for 20,000 hours. This power is used to drive a number of mercury ion bombardment thrusters with specific impulse in the range of 4000-5000 seconds. The NEP description, characteristics, and functional requirements are discussed. These...
Topics: NASA Technical Reports Server (NTRS), COMETS, NUCLEAR ELECTRIC PROPULSION, SPACE EXPLORATION, ION...
Economical unmanned earth orbit transportation for large payloads is evaluated. The high exhaust velocity achievable with electric propulsion is attractive because it minimizes the propellant that must be carried to low earth orbit. Propellant transport is a principal cost item. Electric propulsion subsystems utilizing advanced ion thrusters are compared to magnetoplasmadynamic (MPD) thrust subsystems. For very large payloads, a large lift vehicle is needed to low earth orbit, and argon...
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITS, NUCLEAR ELECTRIC PROPULSION, SOLAR ELECTRIC...
Basic guidelines are presented for a nuclear space power system which utilizes heat pipes to transport thermal power from a fast nuclear reactor to an out of core thermionic converter array. Design parameters are discussed for the nuclear reactor, heat pipes, thermionic converters, shields (neutron and gamma), waste heat rejection systems, and the electrical bus bar-cable system required to transport the high current/low voltage power to the processing equipment. Dimensions are compatible with...
Topics: NASA Technical Reports Server (NTRS), NUCLEAR ELECTRIC PROPULSION, SPACE POWER REACTORS, SPACECRAFT...
A nuclear electric propulsion concept using a thermionic reactor inductively coupled to a magnetoplasmadynamic accelerator (MPD arc jet) is described, and the results of preliminary analyses are presented. In this system, the MPD thruster operates intermittently at higher voltages and power levels than the thermionic generating unit. A typical thrust pulse from the MPD arc jet is characterized by power levels of 1 to 4 MWe, a duration of 1 msec, and a duty cycle of approximately 20%. The...
Topics: NASA Technical Reports Server (NTRS), ION ENGINES, MAGNETOHYDRODYNAMICS, NUCLEAR ELECTRIC...
The generation of a charge exchange plasma by a thruster, the transport of this plasma to the solar array, and the interaction of the solar array with the plasma after it arrives are all described. The generation of this plasma is described accurately from thruster geometry and operating conditions. The transport of the charge exchange plasma was studied experimentally with a 15 cm thruster. A model was developed for simple thruster array configurations. A variety of experiments were surveyed...
Topics: NASA Technical Reports Server (NTRS), CHARGE EXCHANGE, ION ENGINES, PLASMA PHYSICS, SOLAR ARRAYS,...
Theoretic converter outputs and efficiencies indicate the need to consider thermionic energy conversion (TEC) with greater power densities and higher temperatures within reasonable limits for space missions. Converter-output power density, voltage, and efficiency as functions of current density were determined for 1400-to-2000 K emitters with 725-to-1000 K collectors. The results encourage utilization of TEC with hotter-than-1650 K emitters and greater-than-6W sq cm outputs to attain better...
Topics: NASA Technical Reports Server (NTRS), AEROSPACE ENGINEERING, CURRENT DENSITY, HIGH TEMPERATURE...
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.
Topics: NASA Technical Reports Server (NTRS), ENERGY CONVERSION EFFICIENCY, NUCLEAR ELECTRIC PROPULSION,...
Major strategies for exploring the solar system focus on the return of information and the return of matter. Both the planetary exploration facility, and an orbiting automated space station, and the sample return and exploration facility have similar requirements. The single most essential need to enable intensive study of the outer solar system is nuclear propulsion and power capability. New initiatives in 1978 related to the reactor, data and sample acquisition and return, navigation, and...
Topics: NASA Technical Reports Server (NTRS), MISSION PLANNING, NASA PROGRAMS, SOLAR SYSTEM, SPACE...
Three output power coupling methods which can eliminate the high temperature insulator from the Nuclear Electric Propulsion (NEP) power system are described and estimates of their effects on the NEP system masses and cooling requirements are presented. Nominal 400 kWe power systems using push-pull and flux reset inductive output coupling are shown to have specific masses of 22.2 kg/kWe and 18.8 kg/kWe, respectively. Series connected heat pipe systems, which use the heat pipe-to-heat pipe...
Topics: NASA Technical Reports Server (NTRS), NUCLEAR ELECTRIC PROPULSION, POWER CONDITIONING, THERMIONIC...
Various aspects of achieving a low mass heat pipe radiator for the nuclear electric propulsion spacecraft were studied. Specific emphasis was placed on a concept applicable to a closed Brayton cycle power sub-system. Three aspects of inter-related problems were examined: (1) the armor for meteoroid protection, (2) emissivity of the radiator surface, and (3) the heat pipe itself. The study revealed several alternatives for the achievement of the stated goal, but a final recommendation for the...
Topics: NASA Technical Reports Server (NTRS), HEAT PIPES, METEOROID PROTECTION, SPACECRAFT RADIATORS,...
The development of electric propulsion systems is discussed and the benefits of these systems to various space mission requirements are outlined. The characteristics and development status of 8 and 30 cm mercury ion thrusters and solar electric propulsion systems are reported. In addition the advantages of an inert gas thruster for Earth orbital missions are examined and include its capability for operation at higher values of specific impulse, the ease at which it can be integrated with space...
Topics: NASA Technical Reports Server (NTRS), ELECTRIC PROPULSION, LARGE SPACE STRUCTURES, SPACECRAFT...
Efforts were made to develop a thermionic energy conversion TEC technology appropriate for nuclear electric propulsion missions. This space TEC effort was complementary to the terrestrial TEC studies sponsored by the Department of Energy which had the goal of topping fossil fuel power plants. Thermionic energy conversion was a primary conversion option for space reactors because of its: (1) high operating temperature; (2) lack of moving parts; (3) modularity; (4) established technology; and (5)...
Topics: NASA Technical Reports Server (NTRS), ENERGY CONVERSION EFFICIENCY, NUCLEAR ELECTRIC PROPULSION,...
The critical evaluation and subsequent redesign of the power conversion subsystem of the spacecraft are covered. As part of that evaluation and redesign, prototype heat pipe components for the heat rejection system were designed fabricated and tested. Based on the results of these tests in conjunction with changing mission requirements and changing energy conversion devices, new system designs were investigated. The initial evaluation and redesign was based on state-of-the-art fabrication and...
Topics: NASA Technical Reports Server (NTRS), FABRICATION, HEAT PIPES, HEAT RADIATORS, NUCLEAR ELECTRIC...
The feasibility of using Brayton power systems for nuclear electric spacecraft was investigated. The primary performance parameters of systems mass and radiator area were determined for systems from 100 to 1000 kW sub e. Mathematical models of all system components were used to determine masses and volumes. Two completely independent systems provide propulsion power so that no single-point failure can jeopardize a mission. The waste heat radiators utilize armored heat pipes to limit meteorite...
Topics: NASA Technical Reports Server (NTRS), BRAYTON CYCLE, ELECTRIC ROCKET ENGINES, HEAT PIPES, HEAT...
Automated interstellar space exploration is reviewed. The Titan demonstration mission is discussed. Remote sensing and automated modeling are considered. Nuclear electric propulsion, main orbiting spacecraft, lander/rover, subsatellites, atmospheric probes, powered air vehicles, and a surface science network comprise mission component concepts. Machine, intelligence in space exploration is discussed.
Topics: NASA Technical Reports Server (NTRS), ARTIFICIAL INTELLIGENCE, INTERSTELLAR TRAVEL, REMOTE SENSING,...
Two different heat pipe radiator elements, one intended for use with the power conversion subsystem of the NASA funded nuclear electric propulsion (NEP) spacecraft, and one intended for use with the DOE funded space power advanced reactor (SPAR) system were tested and evaluated. The NEP stainless steel/sodium heat pipe was 4.42 meters long and had a 1 cm diameter. Thermal performance testing at 920 K showed a non-limited power level of 3560 watts, well in excess of the design power of 2600...
Topics: NASA Technical Reports Server (NTRS), HEAT PIPES, NUCLEAR ELECTRIC PROPULSION, SPACECRAFT...
A nuclear space power system the SP-100 is being developed for future missions where large amounts of electrical power will be required. Although it is primarily intended for unmanned spacecraft, it can be adapted to a manned space platform by tethering it above the station through an electrical transmission line which isolates the reactor far away from the inhabited platform and conveys its power back to where it is needed. The transmission line, used in conjunction with an instrument rate...
Topics: NASA Technical Reports Server (NTRS), MISSION PLANNING, NUCLEAR ELECTRIC PROPULSION, SPACE...
Conceptual designs for O2/H2 chemical and resistojet propulsion systems for the space station was developed and evaluated. The evolution of propulsion requirements was considered as the space station configuration and its utilization as a space transportation node change over the first decade of operation. The characteristics of candidate O2/H2 auxiliary propulsion systems are determined, and opportunities for integration with the OTV tank farm and the space station life support, power and...
Topics: NASA Technical Reports Server (NTRS), HYDROGEN OXYGEN ENGINES, NUCLEAR ELECTRIC PROPULSION,...
The feasibility is investigated of using nuclear electric propulsion (NEP) for slow freighter ships traveling from a 500 km low Earth orbit (LEO) to the Moon's orbit about the Earth, and on to Mars. NEP is also shown to be feasible for transporting people to Mars on long conjunction-class missions lasting about nine months one way, and on short sprint missions lasting four months one way. Generally, it was not attempted to optimize ion exhaust velocities, but rather suitable parameters to...
Topics: NASA Technical Reports Server (NTRS), CHEMICAL PROPULSION, EXHAUST VELOCITY, ION PROPULSION, MANNED...
A propulsion system (PEGASUS) consisting of an electric thruster driven by a multimegawatt nuclear power system is proposed for a manned Mars mission. Magnetoplasmadynamic and mercury-ion thrusters are considered, based on a mission profile containing a 510-day burn time (for a mission time of approximately 1000 days). Both thrusters are capable of meeting the mission parameters. Electric propulsion systems have significant advantages over chemical systems, because of high specific impulse,...
Topics: NASA Technical Reports Server (NTRS), LONG DURATION SPACE FLIGHT, MANNED SPACE FLIGHT, MARS...
