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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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Department of Energy: Office of Scientific and Technical Information

The international acquisitions functions and activities of the Office of Scientific and Technical Information (OSTI) are described. There are four mechanisms for obtaining foreign information related to energy and nuclear science: The Energy Technology Data Exchange consisting of 14 member countries and 2 associate members; the International Nuclear Information System consisting of 86 countries and 17 international organizations; the Nuclear Energy Agency's 19 member countries provide reports for departmental scientists' use; bilateral agreements with countries such as Germany, the Nordic Consortium, and Australia result in records of foreign research in progress.

Grissom, Catherine↗

A hydrogen energy carrier. Volume 1: Summary

The production, technology, transportation, and implementation of hydrogen into the energy system are discussed along with the fossil fuel cycle, hydrogen fuel cycle, and the demands for energy. The cost of hydrogen production by coal gasification; electrolysis by nuclear energy, and solar energy are presented. The legal aspects of a hydrogen economy are also discussed.

Savage, R. L.↗

Evidence for supermassive stars in three Seyfert galaxy nuclei from IUE spectra

The variability in the ultraviolet continua and the C IV 1550 A emission profiles in the three Seyfert 1 galaxies NGC 4151, NGC 5548, and Fairall 9 are consistent with origin in supermassive stars undergoing explosive mass loss. Blackbody fits to continua of each imply a single thermal source whose area either remains constant or increases moderately as its temperature decreases, with the surface area consistent with stars having masses from 10 to the 6th to 10 to the 8th solar mass. Line emission profiles of C IV 1550 A in the same spectra are individually consistent with uniform expansion of shells of emitting gas expelled from the stars at radial velocities from 10,000 to 16,000 km/s. The kinetic energy removed by repetitive production of such massive shells approximately balances the nuclear energy production expected from supermassive stars of the indicated size. Finally, the observed nature and time scale of the variability of NGC 4151 is consistent with the relatively sudden appearance, and subsequent cooling, of the underlying superstellar surface as one such shell becomes transparent during its expansion.

Stoner, R.↗

Low Level Neutron Spectroscopy

Although the most sought-after hot plasma fusion reactions use deuterium-tritium due to its higher fusion cross-section, the deuteron-deuteron fusion reaction is also used and is suspected in Low Energy Nuclear Reactions (LENR). Although LENR reactions are largely aneutronic, the D(d,n)3He reaction produces a 2.45 MeV kinetic energy neutron. In the course of fusion experiments at NASA, ranging from bremsstrahlung photoneutron-initiated fusion to Pd/D co-deposition, we’ve made use of liquid and solid neutron scintillator spectrometers, bubble detectors and Solid State Nuclear Track Detectors (CR-39). We have observed the unfolded neutron energy spectrum from primary fusion and boosted fusion or stripped neutrons from photoneutron induced fusion. Despite an average deuteron energy of 64 keV, the peak unfolded neutron flux was only a few neutrons/minute. The major problem was the 10e14vgamma ray/neutrons/second flux ratio.

Neutron spectroscopy↗

CFD Multiphysics Tool

The recent bold initiatives to expand the human presence in space require innovative approaches to the design of propulsion systems whose underlying technology is not yet mature. The space propulsion community has identified a number of candidate concepts. A short list includes solar sails, high-energy-density chemical propellants, electric and electromagnetic accelerators, solar-thermal and nuclear-thermal expanders. For each of these, the underlying physics are relatively well understood. One could easily cite authoritative texts, addressing both the governing equations, and practical solution methods for, e.g. electromagnetic fields, heat transfer, radiation, thermophysics, structural dynamics, particulate kinematics, nuclear energy, power conversion, and fluid dynamics. One could also easily cite scholarly works in which complete equation sets for any one of these physical processes have been accurately solved relative to complex engineered systems. The Advanced Concepts and Analysis Office (ACAO), Space Transportation Directorate, NASA Marshall Space Flight Center, has recently released the first alpha version of a set of computer utilities for performing the applicable physical analyses relative to candidate deep-space propulsion systems such as those listed above. PARSEC, Preliminary Analysis of Revolutionary in-Space Engineering Concepts, enables rapid iterative calculations using several physics tools developed in-house. A complete cycle of the entire tool set takes about twenty minutes. PARSEC is a level-zero/level-one design tool. For PARSEC s proof-of-concept, and preliminary design decision-making, assumptions that significantly simplify the governing equation sets are necessary. To proceed to level-two, one wishes to retain modeling of the underlying physics as close as practical to known applicable first principles. This report describes results of collaboration between ACAO, and Embry-Riddle Aeronautical University (ERAU), to begin building a set of level-two design tools for PARSEC. The "CFD Multiphysics Tool" will be the propulsive element of the tool set. The name acknowledges that space propulsion performance assessment is primarily a fluid mechanics problem. At the core of the CFD Multiphysics Tool is an open-source CFD code, HYP, under development at ERAU. ERAU is renowned for its undergraduate degree program in Aerospace Engineering the largest in the nation. The strength of the program is its applications-oriented curriculum, which culminates in one of three two-course Engineering Design sequences: Aerospace Propulsion, Spacecraft, or Aircraft. This same philosophy applies to the HYP Project, albeit with fluid physics modeling commensurate with graduate research. HYP s purpose, like the Multiphysics Tool s, is to enable calculations of real (three-dimensional; geometrically complex; intended for hardware development) applications of high speed and propulsive fluid flows.

Perrell, Eric R.↗

Feasibility of Interstellar Travel

The feasibility of interstellar flight is discussed. Mathematical equations for single-stage and multistage rocket propulsion are developed; velocity data and transit times are presented. The conclusions indicate that interstellar travel is theoretically feasible by utilizing known staged nuclear-energy systems.

Interstellar Travel↗

Properties of P-03 graphite

Thermal and mechanical properties of P-03 graphite evaluated for nuclear energy for rocket vehicle reactor hardware

HARDWARE↗

A search for solar flare positrons

The detection of solar gamma-ray line emission and observations of the isotopes H2, H-3, and He-3 in solar cosmic rays provide direct evidence for the occurrence of high energy nuclear reactions in solar flare events. Appreciable numbers of other reaction products, including positrons with energies near about 1 MeV, should also be produced in such events. We have searched for positrons in the 0.16-1.6 MeV energy interval during 5 H-3 rich solar particle events. Based on calculations of positron and He-3 production at the sun, and using a simplified model of interplanetary propagation, we might expect comparable fluences of positrons and He-3 to be observed. Summing over these 5 events, we find the 0.16 to 1.6 MeV positron fluence to be a maximum of about 10% of the He-3 fluence with more tnan 1 MeV/nuc. This suggests that other processes, such as preferential trapping by the solar magnetic field, may be important.

Mewaldt, R. A.↗

Proton and heavy ion acceleration facilities for space radiation research

The particles and energies commonly used for medium energy nuclear physics and heavy charged particle radiobiology and radiotherapy at particle accelerators are in the charge and energy range of greatest interest for space radiation health. In this article we survey some of the particle accelerator facilities in the United States and around the world that are being used for space radiation health and related research, and illustrate some of their capabilities with discussions of selected accelerator experiments applicable to the human exploration of space.

NASA Discipline Radiation Health↗

Information and Best Practices Related to NASA Nuclear Flight Safety for Space Flights Involving Space Nuclear Systems

The purpose of this handbook is to facilitate a repeatable and robust process that promotes clear and effective interfaces between activities and stakeholders focused on meeting nuclear flight safety requirements for missions utilizing space nuclear systems (SNS), within the context of NASA’s broader nuclear-related activities and interfaces. NPR 8715.26, Nuclear Flight Safety, requires that the NASA project manager “incorporate nuclear flight safety considerations starting with program or project formulation through the point at which the SNS or other radioactive material no longer has the potential to affect Earth’s biosphere.” NASA’s use of SNS inherently involves partnering with other stakeholders to conduct a range of related activities that interface with nuclear flight safety. From a categorical perspective these include: (i) meeting the authorities and licensing requirements for possession and use of nuclear material, as governed by other Federal authorities; (ii) conducting National Environmental Policy Act (NEPA) activities for nuclear-enabled missions; (iii) meeting Federal nuclear launch authorization requirements; (iv) conducting radiological contingency planning activities, including those associated with international commitments; (v) performing risk communication and public outreach activities; and (vi) ensuring decommissioning and disposal strategies reflect National policies and interests. It is the intent of this handbook to promote an effective interface between nuclear flight safety and these interrelated categorical activities. In addition to activities undertaken with partnering agencies, there are individual nuclear-related activities and programs that have a nexus to nuclear flight safety, and these include: (i) applicable NASA Standing Review Boards; (ii) the US Department of Energy nuclear safety activities conducted in partnership with NASA under Memoranda of Understanding; (iii) the Department of Defense’s Range Safety activities; (iv) NASA’s general involvement in interagency and international dialogues regarding nuclear safety; (v) the NASA-administered Interagency Nuclear Safety Review Board; (vi) NASA’s program and project governance activities and nuclear-specific Technical Discipline Team activities under the Office of the Chief Engineer; and others. It is the intent of this handbook to promote effective leveraging of these additional interrelated organizational activities, as appropriate.

Donald Helton↗

A nuclear driven metallic vapor MHD coupled with MPD thrusters

Nuclear energy as a source of power for space missions, represents an enabling technology for advanced and ambitious space applications. Nuclear fuel in a gaseous or liquid form has been configured as a promising and practical candidate in this regard. The present study investigates and performs a feasibility analysis of an innovative concept for space power generation and propulsion. The system embodies a conceptual nuclear reactor with an MHD generator and coupled to MPD thrusters. The reactor utilizes liquid uranium in droplet form as fuel and superheated metallic vapor as the working fluid. This ultrahigh temperature vapor core reactor brings forward varied and challenging technical issues, and it has been addressed to in this paper. A parametric study of the conceived system has been performed in a qualitative and quantitative manner. Preliminary results show enough promise for further indepth analysis of this novel system.

Anghaie, Samim↗

Accessing Icy World Oceans using Lattice Confinement Fusion Fast Fission

Exploring the oceans of icy moons and planets requires a robust robotic probe powered by an energy source that can operate under icy world ocean conditions and be self-contained. We propose a non-fissile, compact, scalable nuclear energy source to electrically power untethered, autonomous probes to melt or bore through icy world crusts. The probe can be used for planetary (i.e. Pluto, lunar (i.e., Europa), or asteroid exploration (i.e. Ceres) where ice caps are encountered. This new approach may yield a variable output fission power source with a higher performance than 238Pu and a non-fissile alternative to a highly enriched uranium (HEU) core. This approach saves uranium enrichment expense, and both HEU and 238Pu security and launch safety costs. The reactor will produce electrical power with thermal waste heat to melt through the ice crust with possible sonic assistance. This paper will introduce the hybrid fusion-fission reactor concept, explore the potential for and benefits of this new type of nuclear reactor, and discuss the technical approach to developing this new technology.

Theresa L Benyo↗

Low- and medium-energy galactic gamma-ray observations

Observation of 0.2 to 100 MeV-diffuse gamma-radiation emitted from a galaxy provides information on the intensities of 5 to 50 MeV/nucleon cosmic-rays and approximately less than 50-MeV electrons in interstellar space. Recent measurements of gamma-rays emitted from the galactic center region provide evidence for a diffuse continuum between 10 and 100 MeV, which is dominant over the pi-decay emission generated in high-energy nuclear collisions. The intensities of the recently reported nuclear line gamma-rays, also observed in the direction of the galactic center, require the presence of intense fluxes of low energy cosmic rays in the inner galaxy if the gamma-ray are produced on a galactic scale. Current detection techniques for 0.1 to 100 MeV gamma-ray measurements are summarized, and their capabilities for measuring the diffuse galactic emission are evaluated.

Share, G. H.↗

Accessing Icy Worlds Using Lattice Confinement Fusion (LCF) Fast Fission

Exploring the oceans of icy moons and planets requires a robust robotic probe powered by an energy source that can operate under icy world ocean conditions and be self-contained. We propose a non-fissile, compact, scalable nuclear energy source to electrically power untethered, autonomous probes to melt or bore through icy world crusts. The probe can be used for planetary (i.e. Pluto, lunar (i.e., Europa), or asteroid exploration (i.e. Ceres) where ice caps are encountered. This new approach may yield a variable output fission power source with a higher performance than 238Pu and a non-fissile alternative to a highly enriched uranium (HEU) core. This approach saves uranium enrichment expense, and both HEU and 238Pu security and launch safety costs. The reactor will produce electrical power with thermal waste heat to melt through the ice crust with possible sonic assistance. This NIAC funded proposal and presentation will introduce the hybrid fusion-fission reactor concept applied to the Saturnian moon, Enceladus, explore the potential for and benefits of this new type of nuclear reactor, and discuss applying this new technology.

Icy Worlds↗

Thermal Propulsion Capture System Heat Exchanger Design

One of the biggest challenges of manned spaceflight beyond low earth orbit and the moon is harmful radiation that astronauts would be exposed to on their long journey to Mars and further destinations. Using nuclear energy has the potential to be a more effective means of propulsion compared to traditional chemical engines (higher specific impulse). An upper stage nuclear engine would allow astronauts to reach their destination faster and more fuel efficiently. Testing these engines poses engineering challenges due to the need to totally capture the engine exhaust. The Thermal Propulsion Capture System is a concept for cost effectively and safely testing Nuclear Thermal Engines. Nominally, hydrogen exhausted from the engine is not radioactive, but is treated as such in case of fuel element failure. The Thermal Propulsion Capture System involves injecting liquid oxygen to convert the hydrogen exhaust into steam. The steam is then cooled and condensed into liquid water to allow for storage. The Thermal Propulsion Capture System concept for ground testing of a nuclear powered engine involves capturing the engine exhaust to be cooled and condensed before being stored. The hydrogen exhaust is injected with liquid oxygen and burned to form steam. That steam must be cooled to saturation temperatures before being condensed into liquid water. A crossflow heat exchanger using water as a working fluid will be designed to accomplish this goal. Design a cross flow heat exchanger for the Thermal Propulsion Capture System testing which: Eliminates the need for water injection cooling, Cools steam from 5800 F to saturation temperature, and Is efficient and minimizes water requirement.

Richard, Evan M.↗

The FLUKA code for space applications: recent developments

The FLUKA Monte Carlo transport code is widely used for fundamental research, radioprotection and dosimetry, hybrid nuclear energy system and cosmic ray calculations. The validity of its physical models has been benchmarked against a variety of experimental data over a wide range of energies, ranging from accelerator data to cosmic ray showers in the earth atmosphere. The code is presently undergoing several developments in order to better fit the needs of space applications. The generation of particle spectra according to up-to-date cosmic ray data as well as the effect of the solar and geomagnetic modulation have been implemented and already successfully applied to a variety of problems. The implementation of suitable models for heavy ion nuclear interactions has reached an operational stage. At medium/high energy FLUKA is using the DPMJET model. The major task of incorporating heavy ion interactions from a few GeV/n down to the threshold for inelastic collisions is also progressing and promising results have been obtained using a modified version of the RQMD-2.4 code. This interim solution is now fully operational, while waiting for the development of new models based on the FLUKA hadron-nucleus interaction code, a newly developed QMD code, and the implementation of the Boltzmann master equation theory for low energy ion interactions. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

Non-NASA Center↗