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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
All sourcesNASA NTRSDOE OSTI
NASA NTRS2001

Shielded Heavy-Ion Environment Linear Detector (SHIELD): an experiment for the Radiation and Technology Demonstration (RTD) Mission

Radiological assessment of the many cosmic ion species of widely distributed energies requires the use of theoretical transport models to accurately describe diverse physical processes related to nuclear reactions in spacecraft structures, planetary atmospheres and surfaces, and tissues. Heavy-ion transport models that were designed to characterize shielded radiation fields have been validated through comparison with data from thick-target irradiation experiments at particle accelerators. With the RTD Mission comes a unique opportunity to validate existing radiation transport models and guide the development of tools for shield design. For the first time, transport properties will be measured in free-space to characterize the shielding effectiveness of materials that are likely to be aboard interplanetary space missions. Target materials composed of aluminum, advanced composite spacecraft structure and other shielding materials, helium (a propellant) and tissue equivalent matrices will be evaluated. Large solid state detectors will provide kinetic energy and charge identification for incident heavy-ions and for secondary ions created in the target material. Transport calculations using the HZETRN model suggest that 8 g cm -2 thick targets would be adequate to evaluate the shielding effectiveness during solar minimum activity conditions for a period of 30 days or more.

NASA Center LaRC↗
NASA NTRS2010

Advanced Space Fission Propulsion Systems

Fission has been considered for in-space propulsion since the 1940s. Nuclear Thermal Propulsion (NTP) systems underwent extensive development from 1955-1973, completing 20 full power ground tests and achieving specific impulses nearly twice that of the best chemical propulsion systems. Space fission power systems (which may eventually enable Nuclear Electric Propulsion) have been flown in space by both the United States and the Former Soviet Union. Fission is the most developed and understood of the nuclear propulsion options (e.g. fission, fusion, antimatter, etc.), and fission has enjoyed tremendous terrestrial success for nearly 7 decades. Current space nuclear research and technology efforts are focused on devising and developing first generation systems that are safe, reliable and affordable. For propulsion, the focus is on nuclear thermal rockets that build on technologies and systems developed and tested under the Rover/NERVA and related programs from the Apollo era. NTP Affordability is achieved through use of previously developed fuels and materials, modern analytical techniques and test strategies, and development of a small engine for ground and flight technology demonstration. Initial NTP systems will be capable of achieving an Isp of ~900 s at a relatively high thrust-to-weight ratio. The development and use of first generation space fission power and propulsion systems will provide new, game changing capabilities for NASA. In addition, development and use of these systems will provide the foundation for developing extremely advanced power and propulsion systems capable of routinely and affordably accessing any point in the solar system. The energy density of fissile fuel (8 x 10(exp 13) Joules/kg) is more than adequate for enabling extensive exploration and utilization of the solar system. For space fission propulsion systems, the key is converting the virtually unlimited energy of fission into thrust at the desired specific impulse and thrust-to-weight ratio. This presentation will discuss potential space fission propulsion options ranging from first generation systems to highly advanced systems. Ongoing research that shows promise for enabling second generation NTP systems with Isp greater than 1000 s will be discussed, as will the potential for liquid, gas, or plasma core systems. Space fission propulsion systems could also be used in conjunction with simple (water-based) propellant depots to enable routine, affordable missions to various destinations (e.g. moon, Mars, asteroids) once in-space infrastructure is sufficiently developed. As fuel and material technologies advance, very high performance Nuclear Electric Propulsion (NEP) systems may also become viable. These systems could enable sophisticated science missions, highly efficient cargo delivery, and human missions to numerous destinations. Commonalities between NTP, fission power systems, and NEP will be discussed.

Houts, Michael G.↗
NASA NTRS1990

Space exploration and colonization - Towards a space faring society

Development trends of space exploration and colonization since 1957 are reviewed, and a five-phase evolutionary program planned for the long-term future is described. The International Geosphere-Biosphere program which is intended to provide the database on enviromental changes of the earth as a global system is considered. Evolution encompasses the anticipated advantages of such NASA observation projects as the Hubble Space Telescope, the Gamma Ray Observatory, the Advanced X-Ray Astrophysics Facility, and the Cosmic Background Explorer. Attention is given to requirements for space colonization, including development of artificial gravity and countermeasures to mitigate zero gravity problems; robotics and systems aimed to minimize human exposure to the space environment; the use of nuclear propulsion; and international collaboration on lunar-Mars projects. It is recommended that nuclear energy sources be developed for both propulsion and as extraterrestrial power plants.

Hammond, Walter E.↗
NASA NTRS1991

Gamma Ray Observatory (GRO) Prelaunch Mission Operations Report (MOR)

The NASA Astrophysics Program is an endeavor to understand the origin and fate of the universe, to understand the birth and evolution of the large variety of objects in the universe, from the most benign to the most violent, and to probe the fundamental laws of physics by examining their behavior under extreme physical conditions. These goals are pursued by means of observations across the entire electromagnetic spectrum, and through theoretical interpretation of radiations and fields associated with astrophysical systems. Astrophysics orbital flight programs are structured under one of two operational objectives: (1) the establishment of long duration Great Observatories for viewing the universe in four major wavelength regions of the electromagnetic spectrum (radio/infrared/submillimeter, visible/ultraviolet, X-ray, and gamma ray), and (2) obtaining crucial bridging and supporting measurements via missions with directed objectives of intermediate or small scope conducted within the Explorer and Spacelab programs. Under (1) in this context, the Gamma Ray Observatory (GRO) is one of NASA's four Great Observatories. The other three are the Hubble Space Telescope (HST) for the visible and ultraviolet portion of the spectrum, the Advanced X-ray Astrophysics Facility (AXAF) for the X-ray band, and the Space Infrared Telescope Facility (SIRTF) for infrared wavelengths. GRO's specific mission is to study the sources and astrophysical processes that produce the highest energy electromagnetic radiation from the cosmos. The fundamental physical processes that are known to produce gamma radiation in the universe include nuclear reactions, electron bremsstrahlung, matter-antimatter annihilation, elementary particle production and decay, Compton scattering, synchrotron radiation. GRO will address a variety of questions relevant to understanding the universe, such as: the formation of the elements; the structure and dynamics of the Galaxy; the nature of pulsars; the existence of black holes; the possible existence of large amounts of antimatter, energetic and explosive phenomena occurring in galactic nuclei; the origin of the cosmic diffuse background; particle acceleration in the Sun, stars and stellar systems; processes in supernovae; and the origin and evolution of the universe itself.

Source record↗
NASA NTRS2000

External Pulsed Plasma Propulsion (EPPP) Analysis Maturation

External Pulsed Plasma Propulsion (EPPP) systems are at the stage of engineering infancy with evolving paradigms for application. performance and general characteristics. Recent efforts have focused on an approach that employs existing technologies with near term EPPP development for usage in interplanetary exploration and asteroid/comet deflection. if mandated. The inherent advantages of EPPP are discussed and its application to a variety of propulsion concepts is explored. These include, but are not limited to, utilizing energy sources such as fission. fusion and antimatter, as well as, improved chemical explosives. A mars mission scenario is presented as a demonstration of its capability using existing technologies. A suggested alternate means to improve EPPP efficiencies could also lead to a heavy lift (non-nuclear) launch vehicle capability. Conceivably, true low-cost, access to space is possible using advanced explosive propellants and/or coupling the EPPP vehicle to a "beam propellant" concept. EPPP systems appear to offer an approach that can potentially cover ETO through interstellar transportation capability. A technology roadmap is presented that shows mutual benefits pertaining to a substantial number of existing space propulsion and research areas.

Bonometti, Joesph A.↗
NASA NTRSDate not supplied

Contamination, Transportation or Transmutation in LENR Material Analyses

LENR experiments using various loading and triggering mechanisms rely on a variety of elemental and isotopic assays to determine LENR effects. These assays include optical microscopy, Scanning Electron Microscopy with Energy Dispersive X-Ray Analysis (SEM/EDX), X-Ray Photoelectron Spectroscopy (XPS) and Transmission Electron Microscopy (TEM). All of these methods observe the surface of a material. By dissolving or vaporizing the sample, Inductively Coupled Plasma Optical Element Spectroscopy (ICP-OES) can determine elemental composition (ppb) or with mass spectroscopy, isotopes (ICP/MS). One can use a focused ion beam (FIB) to cut open a sample and observe the “cut” with either SEM/EDX, or Time-of-Flight Secondary Ion Mass Spectroscopy (TOF-SIMS). High Purity Gamma Ray Spectroscopy (HPGe) and alpha/ beta Liquid Scintillator spectroscopy can be used. We’ve employed these assay methods in our NASA GRC research under both the Advanced Energy Conversion and Lattice Confinement Fusion Projects. However, there are limitations associated with each of these methods ranging from handling contamination, instrumental limitations including sensitivity and field of view, and sample preparation.

Low Energy Nuclear Reactions↗
NASA NTRSDate not supplied

Refractory Carbides for Hydrogen Erosion Resistance in Carbon Tubes for Nuclear Thermal Propulsion

As crewed travel becomes more common to the Moon and beyond, space nuclear propulsion-based craft offer reduced travel times and double the specific impulse compared to conventional chemical rockets. The nuclear core and its integral hydrogen propellant channels will require advanced refractory carbide coatings over a carbon/carbon substrate for hydrogen resistance. Using ab initio and other computational techniques, we studied select (Zr/Ta/Nb)C mixed carbide systems for erosion resistance and hydrogen diffusion using realistic levels of carbon vacancies and experimentally obtainable stoichiometries. Various contributions to the formation and hydrogen erosion free energies were calculated, including configurational, electronic, and vibrational terms. Our calculations indicate that ZrC is less likely to lose carbon than NbC or TaC, providing an explanation for heritage NERVA data on ZrC and NbC mass loss performance. Additionally, binary mixtures show compositions that are more stable than their end-member counterparts. Hydrogen diffusion in stoichiometric ZrC was found to be slightly higher than previously theorized, with the caveat that hydrogen saturation of carbon vacancies will hinder further hydrogen diffusion through the bulk, while hydrogen diffusion in ZrNbC is slightly enhanced over ZrC. And finally, we show that as carbon is depleted, the deformation mechanism of ZrC changes from brittle to ductile. Though many questions still remain as to the bulk performance of these materials, these trends and results are important in terms of materials selection efforts for hydrogen-resistant coatings on carbon/carbon substrates.

William C Tucker↗
NASA NTRSDate not supplied

Refractory Carbides for Hydrogen Erosion Resistance in Carbon Tubes for Nuclear Thermal Propulsion

As crewed travel becomes more common to the Moon and beyond, space nuclear propulsion-based craft offer reduced travel times and double the specific impulse compared to conventional chemical rockets. The nuclear core and its integral hydrogen propellant channels will require advanced refractory carbide coatings over a carbon/carbon substrate for hydrogen resistance. Using ab initio and other computational techniques, we studied select (Zr/Ta/Nb)C mixed carbide systems for erosion resistance and hydrogen diffusion using realistic levels of carbon vacancies and experimentally obtainable stoichiometries. Various contributions to the formation and hydrogen erosion free energies were calculated, including configurational, electronic, and vibrational terms. Our calculations indicate that ZrC is less likely to lose carbon than NbC or TaC, providing an explanation for heritage NERVA data on ZrC and NbC mass loss performance. Additionally, binary mixtures show compositions that are more stable than their end-member counterparts. Hydrogen diffusion in stoichiometric ZrC was found to be slightly higher than previously theorized, with the caveat that hydrogen saturation of carbon vacancies will hinder further hydrogen diffusion through the bulk, while hydrogen diffusion in ZrNbC is slightly enhanced over ZrC. And finally, we show that as carbon is depleted, the deformation mechanism of ZrC changes from brittle to ductile. Though many questions still remain as to the bulk performance of these materials, these trends and results are important in terms of materials selection efforts for hydrogen-resistant coatings on carbon/carbon substrates.

William C Tucker↗
NASA NTRS1999

Instellar Exploration: Propulsion Options for Precursors and Beyond

NASA is considering a mission to explore near-interstellar space early in the next decade as the first step toward a vigorous interstellar exploration program. A key enabling technology for such an ambitious science and exploration effort is the development of propulsion systems capable of providing fast trip times; mission duration should not exceed the professional lifetime of the investigative team. Advanced propulsion technologies that might support an interstellar precursor mission early in the next century include some combination of solar sails, nuclear electric propulsion systems, and aerogravity assists. Follow-on missions to far beyond the heliopause will require the development of propulsion technologies that are only at the conceptual stage today. These include 1) matter-antimatter annihilation, 2) beamed-energy sails, and 3) fusion systems. For years, the scientific community has been interested in the development of solar sail technology to support exploration of the inner and outer planets. Progress in thin-film technology and the development of technologies that may enable the remote assembly of large sails in space are only now maturing to the point where ambitious interstellar precursor missions can be considered. Electric propulsion is now being demonstrated for planetary exploration by the Deep Space 1 mission. The primary issues for it's adaptation to interstellar precursor applications include the nuclear reactor that would be required and the engine lifetime. For further term interstellar missions, matter-antimatter annihilation propulsion system concepts have the highest energy density of any propulsion systems using onboard propellants. However, there are numerous challenges to production and storage of antimatter that must be overcome before it can be seriously considered for interstellar flight. Off-board energy systems (laser sails) are candidates for long-distance interstellar flight but development of component technologies and necessary infrastructure have not begun.. Fusion propulsion has been studied extensively. However, fusion technology is still considered immature, even after many decades of well-funded research. Furthermore, fusion alone does not offer high enough energy density to make it a viable candidate for interstellar propulsion unless propellant can be collected in situ, as was considered by R. Bussard for his interstellar ramjet concept. The current research in investigating these propulsion systems will be described, and the range of application of each technology will be explored.

Johnson, Charles Les↗
NASA NTRSDate not supplied

Refractory Carbides for Hydrogen Erosion Resistance in Carbon Tubes for Nuclear Thermal Propulsion

As crewed travel becomes more common to the Moon and beyond, space nuclear propulsion-based craft offer reduced travel times and double the specific impulse compared to conventional chemical rockets. The nuclear core and its integral hydrogen propellant channels will require advanced refractory carbide coatings over a carbon/carbon substrate for hydrogen resistance. Using \textit{ab initio} and other computational techniques, we studied select (Zr/Ta/Nb)C mixed carbide systems for erosion resistance and hydrogen diffusion using realistic levels of carbon vacancies and experimentally obtainable stoichiometries. Various contributions to the formation and hydrogen erosion free energies were calculated, including configurational, electronic, and vibrational terms. Our calculations indicate that ZrC is less likely to lose carbon than NbC or TaC, providing an explanation for heritage NERVA data on ZrC and NbC mass loss performance. Additionally, binary mixtures show compositions that are more stable than their end-member counterparts. Hydrogen diffusion in stoichiometric ZrC was found to be slightly higher than previously theorized, with the caveat that hydrogen saturation of carbon vacancies will hinder further hydrogen diffusion through the bulk, while hydrogen diffusion in ZrNbC is slightly enhanced over ZrC. And finally, we show that as carbon is depleted, the deformation mechanism of ZrC changes from brittle to ductile. Though many questions still remain as to the bulk performance of these materials, these trends and results are important in terms of materials selection efforts for hydrogen-resistant coatings on carbon/carbon substrates.

William C. Tucker↗
NASA NTRSDate not supplied

Moss Tolerance of Deep Space-Like Ionizing Radiation, Singular or Combined With Spaceflight Microgravity-Preparation for the BRIC-27 Experiment to the ISS

Understanding how terrestrial life perceives and tolerates deep space environments is essential to advancing human space exploration missions and searching for life beyond our solar system. Throughout evolution moss adapted to living in extreme environments from the edge of habitability. Moss inhabits areas with high UVB/UVC photon levels such as polar regions subject to ozone holes, high elevation mountain environments, and sites with elevated ionizing particle levels such as those found at nuclear plant accident sites, atomic bomb test sites or radioactive element-rich regions. We investigate if moss tolerance of ionizing radiation encounter terrestrially extends to resistance to deep space ionizing radiation. We exposed moss to high energy ion beams simulating Galactic Cosmic Ray (GCRSim) and Solar Particle Event (SPESim) (NSRL, BNL) that permeate deep space, and moss was unharmed. We also exposed moss to high doses of gamma rays as released in astrophysical events, and moss survived absorption of extremely high doses. Next, we ask if moss tolerance of deep space-like ionizing radiation observed terrestrially differs from that in other deep space environments. In the upcoming BRIC-27 spaceflight experiment we will sequentially expose Antarctic moss C.purpureus to GCRSim and SPESim followed by exposure to spaceflight microgravity and compare gene expression profiles in deep space-like ionizing radiation, singular or combined with spaceflight microgravity. Additionally, we will compare gene expression profiles in spaceflight microgravity, singular or combined with deep space-like ionizing radiation. Hence, BRIC-27 will advance our understanding of the combined effects of both deep space ionizing radiation and microgravity, which may have different and more profound effects on plant physiology and performance than each condition separately.

Agata Klaudia Zupanska↗
NASA NTRS1977

Earth-to-orbit transportation for advanced space facilities

Stages in the development of lift vehicles and related facilities for near-earth space transportation, starting with the Space Shuttle, are reviewed. Data and expected missions for the Lunar Lander, Heavy Lift Vehicle, Orbital Transport Vehicle, Lunar Transport Vehicle, Shuttle plus Intermediate Upper Stage or Shuttle plus FCT are tabulated. Objectives and summary data are tabulated for some programs (low earth orbit space stations, geosynchronous operations, lunar surface sorties, planetary exploration, nuclear waste disposal, satellite energy systems).

Davis, H. P.↗
NASA NTRS1976

Space and energy

Potential contributions of space to energy-related activities are discussed. Advanced concepts presented include worldwide energy distribution to substation-sized users using low-altitude space reflectors; powering large numbers of large aircraft worldwide using laser beams reflected from space mirror complexes; providing night illumination via sunlight-reflecting space mirrors; fine-scale power programming and monitoring in transmission networks by monitoring millions of network points from space; prevention of undetected hijacking of nuclear reactor fuels by space tracking of signals from tagging transmitters on all such materials; and disposal of nuclear power plant radioactive wastes in space.

Bekey, I.↗
NASA NTRS1988

Refractory metal alloys and composites for space nuclear power systems

Space power requirements for future NASA and other U.S. missions will range from a few kilowatts to megawatts of electricity. Maximum efficiency is a key goal of any power system in order to minimize weight and size so that the Space Shuttle may be used a minimum number of times to put the power supply into orbit. Nuclear power has been identified as the primary power source to meet these high levels of electrical demand. One method to achieve maximum efficiency is to operate the power supply, energy conservation system, and related components at relatively high temperatures. For systems now in the planning stages, design temperatures range from 1300 K for the immediate future to as high as 1700 K for the advanced systems. NASA Lewis Research Center has undertaken a research program on advanced technology of refractory metal alloys and composites that will provide baseline information for space power systems in the 1900's and the 21st century. Special emphasis is focused on the refractory metal alloys of niobium and on the refractory metal composites which utilize tungsten alloy wires for reinforcement. Basic research on the creep and creep-rupture properties of wires, matrices, and composites are discussed.

Titran, Robert H.↗
NASA NTRS1986

Power system technologies for the manned Mars mission

The high impulse of electric propulsion makes it an attractive option for manned interplanetary missions such as a manned mission to Mars. This option is, however, dependent on the availability of high energy sources for propulsive power in addition to that required for the manned interplanetary transit vehicle. Two power system technologies are presented: nuclear and solar. The ion thruster technology for the interplanetary transit vehicle is described for a typical mission. The power management and distribution system components required for such a mission must be further developed beyond today's technology status. High voltage-high current technology advancements must be achieved. These advancements are described. In addition, large amounts of waste heat must be rejected to the space environment by the thermal management system. Advanced concepts such as the liquid droplet radiator are discussed as possible candidates for the manned Mars mission. These thermal management technologies have great potential for significant weight reductions over the more conventional systems.

Bents, Dave↗
NASA NTRS1992

US Department of Energy's Efforts in Intelligent Processing Equipment

The Department of Energy (DOE) uses intelligent processing equipment (IPE) technologies to conduct research and development and manufacturing for energy and nuclear weapons programs. This paper highlights several significant IPE efforts underway in DOE. IPE technologies are essential to the accomplishment of DOE's missions, because of the need for small lot production, precision, and accuracy in manufacturing, hazardous waste management, and protection of the environment and the safety and health of the workforce and public. Applications of IPE technologies include environmental remediation and waste handling, advanced manufacturing, and automation of tasks carried out in hazardous areas. DOE laboratories have several key programs that integrate robotics, sensor, and control technologies. These programs embody a considerable technical capability that also may be used to enhance U.S. industrial competitiveness. DOE encourages closer cooperation with U.S. industrial partners based on mutual benefits. This paper briefly describes technology transfer mechanisms available for industrial involvement.

Peavy, Richard D.↗
NASA NTRS2014

Mission Design and Analysis for Suborbital Intercept and Fragmentation of an Asteroid with Very Short Warning Time

Small near-Earth objects (NEOs) approximately 50-150 m in size are far more numerous (hundreds of thousands to millions yet to be discovered) than larger NEOs. Small NEOs, which are mostly asteroids rather than comets, are very faint in the night sky due to their small sizes, and are, therefore, difficult to discover far in advance of Earth impact. Furthermore, even small NEOs are capable of creating explosions with energies on the order of tens or hundreds of megatons (Mt). We are, therefore, motivated to prepare to respond effectively to short warning time, small NEO impact scenarios. In this paper we explore the lower bound on actionable warning time by investigating the performance of notional upgraded Intercontinental Ballistic Missiles (ICBMs) to carry Nuclear Explosive Device (NED) payloads to intercept and disrupt a hypothetical incoming NEO at high altitudes (generally at least 2500 km above Earth). We conduct this investigation by developing optimal NEO intercept trajectories for a range of cases and comparing their performances. Our results show that suborbital NEO intercepts using Minuteman III or SM-3 IIA launch vehicles could achieve NEO intercept a few minutes prior to when the NEO would strike Earth. We also find that more powerful versions of the launch vehicles (e.g., total delta V of approximately 9.5-11 km/s) could intercept incoming NEOs several hours prior to when the NEO would strike Earth, if launched at least several days prior to the time of intercept. Finally, we discuss a number of limiting factors and practicalities that affect whether the notional systems we describe could become feasible.

near- Earth object↗
NASA NTRS2015

Suborbital Intercept and Fragmentation of an Asteroid with Very Short Warning Time Scenario

Small near-Earth objects (NEOs) is approx. 50-150 m in size are far more numerous (hundreds of thousands to millions yet to be discovered) than larger NEOs. Small NEOs, which are mostly asteroids rather than comets, are very faint in the night sky due to their small sizes, and are, therefore, difficult to discover far in advance of Earth impact. Furthermore, even small NEOs are capable of creating explosions with energies on the order of tens or hundreds of megatons (Mt). We are, therefore, motivated to prepare to respond effectively to short warning time, small NEO impact scenarios. In this paper we explore the lower bound on actionable warning time by investigating the performance of notional upgraded Intercontinental Ballistic Missiles (ICBMs) to carry Nuclear Explosive Device (NED) payloads to intercept and disrupt a hypothetical incoming NEO at high altitudes (generally at least 2500 km above Earth). We conduct this investigation by developing optimal NEO intercept trajectories for a range of cases and comparing their performances. Our results show that suborbital NEO intercepts using Minuteman III or SM-3 IIA launch vehicles could achieve NEO intercept a few minutes prior to when the NEO would strike Earth. We also find that more powerful versions of the launch vehicles (e.g., total deltaV is approx. 9.5-11 km/s) could intercept incoming NEOs several hours prior to when the NEO would strike Earth, if launched at least several days prior to the time of intercept. Finally, we discuss a number of limiting factors and practicalities that affect whether the notional systems we describe could become feasible.

Asteroid↗