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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 1,657 records · Page 92
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

Interdisciplinary research and development on the effects of the nature and properties of ceramic materials in the design of advanced structural components

An educational development and supportive research program on ceramic materials established to advance design methodology, improve materials, and develop engineers knowledgable in design with and use of high performance ceramic materials is described. Emphasis is on the structures and related materials problems in a ceramic turbine engine, but applications in coal gasification, solar conversion, and magnetohydrodynamic technologies are considered. Progress of various research projects in the areas of new materials, processing, characterization, and nondestructive testing is reported. Fracture toughness determination, extended X-ray absorption fine structure measurements, and grain boundary effects in beta-alumina are among the topics covered.

Source record↗
NASA NTRS1983

Elevated temperature biaxial fatigue

Biaxial fatigue is often encountered in the complex thermo-mechanical loadings present in gas turbine engines. Engine strain histories can involve non-constant temperature, mean stress, creep, environmental effects, both isotropic and anisotropic materials and non-proportional loading. Life prediction for the general case involving all the above factors is not a practicable research project. The current research program is limited to isothermal fatigue at room temperature and 1200 F of Hastalloy-X for both proportional and non-proportional loading. An improved method for predicting the fatigue life and deformation response under biaxial cycle loading is sought.

Jordan, E. H.↗
NASA NTRS1986

Research and technology, fiscal year 1986, Marshall Space Flight Center

The Marshall Space Flight Center is continuing its vigorous efforts in space-related research and technology. Extensive activities in advanced studies have led to the approval of the Orbital Maneuvering Vehicle as a new start. Significant progress was made in definition studies of liquid rocket engine systems for future space transportation needs and the conceptualization of advanced laucnch vehicles. The space systems definition studies have brought the Advanced X-ray Astrophysics Facility and Gravity Probe-B to a high degree of maturity. Both are ready for project implementation. Also discussed include significant advances in low gravity sciences, solar terrestrial physics, high energy astrophysics, atmospheric sciences, propulsion systems, and on the critical element of the Space Shuttle Main Engine in particular. The goals of improving the productivity of high-cost repetitive operations on reusable transportation systems, and extending the useful life of such systems are examined. The research and technology highlighted provides a foundation for progress on the Hubble Space Telescope, the Space Station, all elements of the Space Transportation System, and the many other projects assigned to this Center.

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NASA NTRS1988

Molecular clouds in the Carina arm - The largest objects, associated regions of star formation, and the Carina arm in the Galaxy

The Columbia CO survey of the southern Galactic plane is used to identify giant molecular clouds and cloud complexes in the Vela-Carina-Centaurus section of the Galaxy. Twenty-seven giant molecular clouds between l = 270 and 300 deg are catalogued and their heliocentric distances given. In addition, 16 clouds at l greater than 300 deg beyond the solar circle extend the catalog to include the very distant portion of the Carina arm. The most massive clouds in the catalog trace the Carina arm over 23 kpc in the plane of the Galaxy. The average mass of these objects is 1.4 x 10 to the 6th solar, and their average spacing along the arm is 700 pc. The composite distribution projected onto the Galactic plane of the largest molecular clouds in the Carina arm and of similarly massive clouds in the first and second quadrants strongly suggests that the Carina and Sagittarius arms form a single spiral arm about 40 kpc in length wrapping two-thirds of the way around the Galaxy. Descriptions of each cloud, including identification of associated star-forming regions, are presented in an appendix.

Grabelsky, D. A.↗
NASA NTRS1990

Advanced X-ray Astrophysics Facility - Extending man's vision into the X-ray universe

The Advanced X-ray Astrophysics Facility will open a clear window into the X-ray universe. This paper presents an overview of the history, objectives, and status of the program and its projected impact on man's knowledge of the cosmos. The program is shown to be a total system composed of subsystems and their interfaces, verification activities, operations considerations, and a comprehensive interface with the scientific community.

Miller, Lee A.↗
NASA NTRS1993

Statistics of highly magnified gravitational images in clusters of galaxies. I - Implications for the clusters. II - Implications for the sources

A study is presently conducted of the probability distribution of observing images of background galaxies that are gravitationally lensed in the form of elongated arcs by clusters of galaxies, as a function of arc width, curvature radius, and the elongation's orientation. An upper limit is obtained on the size of the cores which is smaller than cluster core radii obtained for the gas from the X-ray surface brightness. It is argued that lensing clusters tend to be elongated along the line of sight; projection effects will enhance surface density. In the second part of this work, it is shown that the number of arcs expected in lensing clusters is primarily dependent on the angular size of the sources, since lower magnification is required to generate an arc of fixed length for a larger source.

Miralda-Escude, Jordi↗
NASA NTRS1992

Participation in the north ecliptic pole sky survey

This grant supported research into the nature of the faintest x-ray sources found in the ROSAT All Sky Survey, with particular emphasis on distant clusters of galaxies. The project was broadened to include sources found in the ROSAT deep pointing at the North Ecliptic Pole. Progress on the research is briefly summarized.

Henry, J. Patrick↗
NASA NTRS2005

Connection Between X-Ray Dips and Superluminal Ejections in the Radio Galaxy 3C 120

This work represents a part of a long-term study of the X-ray flux variability of 3C 120 and its relation to flux and structural changes in the radio jet of this galaxy. The grant included fiinding for the rediiction and analysis of data obt,ained during the time pwiod of Rossi XTE cycle 8 (March 1, 2003-February 29, 2004). Prior RXTE observations, combined with single dish monitoring at centimeter wavelengths and 43 GHz mapping (monthly until February 1999 and bimonthly thereafter) of the inner jet with the VLBA, had identified the presence of X-ray dips in the light curves and X-ray spectral hardening 4 weeks prior to the ejection of new VLBI components in the radio jet. This suggested a picture in which the radio jet was fed by accretion events near the black hole. The specific goals of the cycle 8 observations were to better define the relation between the X-ray dips and the radio events using higher sampling, to include more events in the correlation and hence improve the statistics, to look for a possible optical X-ray connection, and to search for quasi periodicities on timescales of 1-3 days. In cycle 8 this project was awarded time for 4 pointings weekly with RXTE.

Aller, Margo F.↗
NASA NTRS2008

NASA Ares I Crew Launch Vehicle Upper Stage Overview

By incorporating rigorous engineering practices, innovative manufacturing processes and test techniques, a unique multi-center government/contractor partnership, and a clean-sheet design developed around the primary requirements for the International Space Station (ISS) and Lunar missions, the Upper Stage Element of NASA's Crew Launch Vehicle (CLV), the "Ares I," is a vital part of the Constellation Program's transportation system. Constellation's exploration missions will include Ares I and Ares V launch vehicles required to place crew and cargo in low-Earth orbit (LEO), crew and cargo transportation systems required for human space travel, and transportation systems and scientific equipment required for human exploration of the Moon and Mars. Early Ares I configurations will support ISS re-supply missions. A self-supporting cylindrical structure, the Ares I Upper Stage will be approximately 84' long and 18' in diameter. The Upper Stage Element is being designed for increased supportability and increased reliability to meet human-rating requirements imposed by NASA standards. The design also incorporates state-of-the-art materials, hardware, design, and integrated logistics planning, thus facilitating a supportable, reliable, and operable system. With NASA retiring the Space Shuttle fleet in 2010, the success of the Ares I Project is essential to America's continued leadership in space. The first Ares I test flight, called Ares 1-X, is scheduled for 2009. Subsequent test flights will continue thereafter, with the first crewed flight of the Crew Exploration Vehicle (CEV), "Orion," planned for no later than 2015. Crew transportation to the ISS will follow within the same decade, and the first Lunar excursion is scheduled for the 2020 timeframe.

Davis, Daniel J.↗
NASA NTRS2020

NASA Air Traffic Management – eXploration (ATM-X) Insight Assessment

The focus of this final Air Traffic Management – eXploration (ATM-X) Insight Assessment (IA) report is to summarize key findings, lessons learned, gaps, and shortfalls from 2018 to 2019 National Aeronautics and Space Administration (NASA) ATM-X research and to share the outcomes from National Airspace System (NAS) stakeholder discussions with the broader community. This report was generated from a comprehensive review of 25 NASA ATM-X research papers and augmented by interviews with 23 NASA researchers as well as three virtual seminars discussing the project findings and priorities with 47 NAS stakeholders. While these papers cover a wide range of relevant topics, they only represent a small portion of the vast amount of ongoing research in this rapidly evolving area by industry, academia, and other agencies. The research summary described here could be further refined and expanded by reviewing additional studies.

air transportation↗
NASA NTRS2023

Move That Goo!

On May 5, 1961, Alan B. Shepard became the first American in space (K. Mars); since then, NASA has made leaps and bounds in space exploration and continues to develop new technologies. Through their X-Hab program, NASA has teamed up with the National Space Grant Foundation to fund our student-centered project with one main goal: Move That Goo! Liquid amine absorption is a method by which CO2 is removed from an environment and is intended to be the primary method for CO2 removal for NASA’s sustained human presence on extraterrestrial bodies such as the Moon and Mars. Liquid amines can be highly viscous when absorbing CO2, thus the team needed to produce a design that could move a high viscosity fluid while staying under the power requirement of 1 kW and allowing a few square meters in a closed system. Prompted by NASA and with the support of our faculty mentors, we have been tasked with the research, development, production, and testing of a system able to move a high viscosity liquid amine which requires adequate air exposure to absorb carbon dioxide from a habitat atmosphere in low gravity. The system is split into two main groups, fluids, and materials, with two separate teams of students assigned to their half of the design. The fluids team is responsible for everything in the design that directly touches the fluid. The materials team is responsible for the test stand to which the fluids team’s design is attached to as well as additive manufacturing material selection. In the first semester, the team focused on brainstorming ideas, design selection, budget creation, and CAD modeling. Multiple concepts were generated but the team decided on a design to get the high viscosity fluid to move around a rectangular channel using a screw conveyor mechanism. The liquid must be moved by the turning screw from the thermal chamber going around a rectangular trough back to the thermal chamber. The screw and the trough geometry will be important to allow for the high viscosity fluid to flow, utilizing surface tension to maintain contact to the trough as seen in Figure 1 below.

Olivia Angst↗
NASA NTRS1997

The Surface Heat Flux as a Function of Ground Cover for Climate Models

Surface heat fluxes were examined as a function of surface properties and meteorological conditions in a 100 km x 100 km grid square at 1-km spatial resolution centered at the location of the First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment (FIFE), the Forest Ecosystem Dynamics site in central Maine, and a semiarid rangeland site around Walnut Gulch, Arizona. This investigation treats the surface heat flux variability within a GCM grid box to provide insight into methods for treating that variability in climate models. The heat fluxes were calculated using NOAA AVHRR and available meteorological data. The average heat fluxes that were estimated using the various area ground-cover representations were compared with the ensemble average heat fluxes for the entire area, which were assumed to be the best representation of the heat fluxes for the areas. Average beat fluxes were estimated for the entire 100 km x 100 km area based on a single ground-cover representation, and the mean error for the area sensible heat flux was about 10% and for the area latent heat flux, 21%. The estimation error was reduced, and in some cases significantly reduced, when the area heat fluxes were estimated by partitioning the area according to significant ground cover. The most significant effect of the partitioning was on the latent heat flux estimates.

Vukovich, Fred M.↗
DOE OSTI2018

LDRD final report: Neutron star science with Nustar

The Nuclear Spectroscopic Telescope Array (NuSTAR, Figure 1), launched in June 2012, helped scientist obtain for the firs time a sensitive high-energy X-ray map of the sky with extraordinary resolution. This pioneering telescope has aided in the understanding of how stars explode and neutron stars (NSs) are born. LLNL is a founding member of the NuSTAR project, with key personnel on its optics and science team. We used NuSTAR to observe and analyze the observations of different NS classes identified in the last decade that are still poorly understood. These studies not only help to comprehend newly discovered astrophysical phenomena and emission processes for members of the NS family, but also expand the utility of such observations for addressing broader questions in astrophysics and other physics disciplines. For example, NSs proved and excellent laboratory to study exotic and extreme phenomena, such as the equation of state of the densest matter known, the behavior of matter in extreme magnetic fields, and the effects of general relativity. At the same time, knowing their accurate populations has profound implications for understanding the life cycle of massive stars, star collapse, and overall galactic evolution. With this project we identified new behavior of NSs, tested model predictions and advanced our understanding of these complex celestial objects. Proper interpretation of NuSTAR observations requires appropriate models of telescope and detector performance and knowledge of how NuSTAR instruments modulate the intrinsic X-ray emission. Our research is of great interest to the astrophysics community and provided LLNL with a leading presence in X-ray astronomy and astrophysics, therefore facilitating participation in next-generation experiments.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2021

Macromolecular phasing using diffraction from multiple crystal forms

A phasing algorithm for macromolecular crystallography is proposed that utilizes diffraction data from multiple crystal forms – crystals of the same molecule with different unit-cell packings (different unit-cell parameters or space-group symmetries). The approach is based on the method of iterated projections, starting with no initial phase information. The practicality of the method is demonstrated by simulation using known structures that exist in multiple crystal forms, assuming some information on the molecular envelope and positional relationships between the molecules in the different unit cells. With incorporation of new or existing methods for determination of these parameters, the approach has potential as a method for ab initio phasing.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

X-RAY EJECTA KINEMATICS OF THE GALACTIC CORE-COLLAPSE SUPERNOVA REMNANT G292.0+1.8

We report on the results from the analysis of our 114 ks Chandra High Energy Transmision Grating Spectrometer observation of the Galactic core-collapse supernova remnant G292.0+1.8. To probe the three-dimensional structure of the clumpy X-ray emitting ejecta material in this remnant, we measured Doppler shifts in emission lines from metal-rich ejecta knots projected at different radial distances from the expansion center. We estimate radial velocities of ejecta knots in the range of –2300 ≲ v{sub r} ≲ 1400 km s{sup –1}. The distribution of ejecta knots in velocity versus projected-radius space suggests an expanding ejecta shell with a projected angular thickness of ∼90'' (corresponding to ∼3 pc at d = 6 kpc). Based on this geometrical distribution of the ejecta knots, we estimate the location of the reverse shock approximately at the distance of ∼4 pc from the center of the supernova remnant, putting it in close proximity to the outer boundary of the radio pulsar wind nebula. Based on our observed remnant dynamics and the standard explosion energy of 10{sup 51} erg, we estimate the total ejecta mass to be ≲8 M {sub ☉}, and we propose an upper limit of ≲35 M {sub ☉} on the progenitor's mass.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2019

Optimization-based simultaneous alignment and reconstruction in multi-element tomography

As x-ray microscopy is pushed into the nanoscale with the advent of more bright and coherent x-ray sources, associated improvement in spatial resolution becomes highly vulnerable to geometrical errors and uncertainties during data collection. We address a form of error in tomography experiments, namely, the drift between projections during the tomographic scan. Our proposed method can simultaneously recover the drift, while tomographically reconstructing the specimen based on a joint iterative optimization scheme. This approach utilizes the correlation provided from different view angles and different signals. Finally, while generally applicable, we demonstrate our method on x-ray fluorescence tomography from a tissue specimen and compare the reconstruction quality with conventional methods.

47 OTHER INSTRUMENTATION↗