Search NASA⌕ Search

SEARCH · Search NASA

Results for “17 - WIND ENERGY”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 379 records · Page 21
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Environmental and socio-economic Pareto-front trade-off analysis of U.S. PET packaging material in a circular economy

Various recycling technologies are emerging to implement circular economy in plasticssupply chain systems. However, the environmental and socio-economic trade-offs of in circular economy are not well understood at a systems level. Particularly, quantifying these trade-offs as a function of end-of-life (EOL) management decisions, including transition of recycling technologies, systems level metrics such as circularity, recycled content, and the need for fossil-derived plastics are not well understood. Here, the present study addressed these research gaps by applying a systems analysis modeling approach that utilizes material flow analysis, life cycle assessment, socioeconomic data, and system optimization techniques for polyethylene terephthalate (PET) packaging supply chains in the United States. Pareto-front trade-offs between conflicting environmental and socio-economic impacts as well as those between socioeconomic impacts and circularity were explored using the epsilon constraint method. The Pareto-front trade-off analysis revealed the transition of EOL management strategies for PET packaging systems, including changes in selection of recycling technologies, to aid decision making process by quantifying studied system metrics. Transitioning from environmentally optimal to socio-economically optimal systems led to increased employment (by 17%), wages (by 26%), and revenues (by 6%) but also led to increased global warming potential (GWP; by 65%), energy consumption (by 59%), and reliance on fossil PET in the system (by 78%). Finally, the results show that there is not a unique set of recycling technologies to achieve a sustainable circular economy of PET packaging system, instead it depends on the decision maker’s objectives and targeted metrics of the system.

54 - ENVIRONMENTAL SCIENCES/GLOBAL CLIMATE CHANGE ↗
DOE OSTI2022

Multi-GeV Electron Bunches from an All-Optical Laser Wakefield Accelerator

We present the first demonstration of multi-GeV laser wakefield acceleration in a fully optically formed plasma waveguide, with an acceleration gradient as high as 25 GeV/m . The guide was formed via self-waveguiding of < 15 J, 45 fs (< ~ 300 TW) pulses over 20 cm in a low-density hydrogen gas jet, with accelerated electron bunches driven up to 5 GeV in quasimonoenergetic peaks of relative energy width as narrow as ~ 15 % , with divergence down to ~ 1mrad and charge up to tens of picocoulombs. Energy gain is inversely correlated with on-axis waveguide density in the range Ne0 = (1.3 – 3.2) x 10 17 cm –3 . We find that shot-to-shot stability of bunch spectra and charge are strongly dependent on the pointing of the injected laser pulse and gas jet uniformity. We also observe evidence of pump depletion-induced dephasing, a consequence of the long optical guiding distance.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2022

Longevity evaluation of SiC based alpha voltaic batteries with surface alpha sources

The alpha emitting actinide 241 Am is electrodeposited on the surface of the Pt electrode of in-house fabricated SiC Schottky diodes. With 17 nCi 241 Am directly coated on the top of a device, the 2-pi geometry yields a high energy (5.486 MeV) and a long-term irradiation accumulating to a high fluence (1.6 × 10 9 alpha particles’ infusion/month). The forward, reverse I/V, and dark current, are periodically measured to monitor key characteristics of device durability for any sign of degradation over time. The direct deposition of actinides on the surface of the device also enables the evaluation of radiation damage through alpha particles’ energy spectroscopic performance, which shows a clear spectrum degradation that can be reversed by optical excitation of the device prior to spectrum acquisition. As an analytical aide, the device performance is also simulated by Allpix 2 . Lastly, this study provides an insight into the durability of 4H-SiC as an energy converter option for alpha-voltaic batteries and the survivability in the other harsh environment found in nuclear fuel cycle, high energy physics, fission, fusion, and space exploration where rad-hard sensors are required.

Americium↗
NASA NTRS1985

Counterstreaming hydrogen and oxygen ions observed in the magnetosphere on ISEE-1

Counterstreaming ions or ions travelling simultaneously both parallel and antiparallel to the magnetic field direction have been briefly noted in the literature but have not been studied previously in depth. Over 60 counterstreaming ion (CSI) events observed on the ISEE-1 satellite have been studied. They were found to occur at altitudes of about 2 to 8 earth radii on L shells of about 5 to 12 in the evening-to-morning sector from about 1700-0900 LT. Often both oxygen and hydrogen ions at a number of energy levels are counterstreaming but some events show only either oxygen or hydrogen ions involved. One particularly interesting event shows only counterstreaming oxygen ions with 417 eV energy; oxygen ions of lower energy (215 eV) and above (630-17,000 eV) and all the hydrogen ions between 215-17,000 eV energy have lower fluxes and/or nearly isotropic pitch angle distributions. This event correlates well with wave activity in the 17-100 Hz band and is also accompanied by 200 eV downgoing and 400 eV upgoing electrons. Details of this event and the other counterstreaming events are presented.

Horita, R. E.↗
NASA NTRS1992

GB 790305 as a very strongly magnetized neutron star

The March 5 1979 event was the strongest gamma-ray burst ever observed. Its location in the sky is known with an accuracy of about 10 arcsec, and it coincides with the N49 supernova remnant in the Large Magellanic Cloud. The main burst was followed by a soft tail with the periodic 8 s modulation, and 16 soft gamma events over the following few years. If the source is a magnetic neutron star with the 8 s rotation period and the age of about 10 exp 4 years as indicated by N49 then the field strength of about 5 x 10 exp 14 gauss is implied. The corresponding critical luminosity is about 10 exp 4 L(Edd), as the electron scattering opacity is suppressed by the strong magnetic field. This luminosity is consistent with the observed peak flux of the soft tail and the soft repeaters. The soft spectrum may be approximated with the photospheric emission at kT(eff) = 17 keV. The corresponding photospheric radius is about 14 km, compatible with a neutron star hypothesis. The total magnetic energy of the star is about 4 x 10 exp 46 erg, more than enough to power the March 5 event and all its repeaters.

Paczynski, Bohdan↗
NASA NTRS1998

Particle Imaging Velocimetry Used in a Transonic Compressor Facility

Particle Imaging Velocimetry (PIV) is an optical technique whereby a pulsed laser sheet is used to illuminate particles entrained in a fluid across an extended planar cross section of a flow field. Electronic recording of the particle positions at two closely timed laser pulses permits the computation of the flow velocity. PIV captures the instantaneous flow field, permitting the study of unsteady flow phenomena. Mean flow statistics can be computed by acquiring several hundred images and averaging the results. The first-ever successful application of PIV to acquire measurements in a high-speed rotating turbomachinery blade row was completed in NASA Lewis Research Center's W-8 Single Stage Axial Compressor Facility. Measurements were acquired in a 20-in.-diameter transonic compressor rotor operating at 17,188 rpm. A custom-designed light-sheet generating probe was used to insert the high-energy, pulsed light-sheet illumination required for recording the unblurred images of particles entrained in the fluid. Measurements of the shock wave formed within the rotor blade passage and of unsteady structures within the blade wakes were acquired. These measurements provide insight into unsteady spatial structures in the flow field which cannot be measured with the more conventional laser anemometry technique. The PIV technique provides both instantaneous and average velocity data in a transonic compressor in an order of magnitude less time than required for other conventional optical diagnostic techniques.

Wernet, Mark P.↗
DOE OSTI2020

Blazar variability power spectra from radio up to TeV photon energies: Mrk 421 and PKS 2155−304

ABSTRACT We present the results of the power spectral density (PSD) analysis for the blazars Mrk 421 and PKS 2155−304, using good-quality, densely sampled light curves at multiple frequencies, covering 17 decades of the electromagnetic spectrum, and variability time-scales from weeks up to a decade. The data were collected from publicly available archives of observatories at radio from Owens Valley Radio Observatory, optical and infrared (B, V, R, I, J, H, and Kbands), X-rays from the Swift and the Rossi X-ray Timing Explorer, high and very high energy (VHE) γ-rays from the Fermi and Very Energetic Radiation Imaging Telescope Array System as well as the High Energy Stereoscopic System. Our results are: (1) the power-law form of the variability power spectra at radio, infrared, and optical frequencies have slopes ∼1.8, indicative of random-walk-type noise processes; (2) the power-law form of the variability power spectra at higher frequencies, from X-rays to VHE γ-rays, however, have slopes ∼1.2, suggesting a flicker noise-type process; and (3) there is significantly more variability power at X-rays, high and VHE γ-rays on time-scales ≲ 100 d, as compared to lower energies. Our results do not easily fit into a simple model, in which a single compact emission zone is dominating the radiative output of the blazars across all the time-scales probed in our analysis. Instead, we argue that the frequency-dependent shape of the variability power spectra points out a more complex picture, with highly inhomogeneous outflow producing non-thermal emission over an extended, stratified volume.

Goyal, Arti↗
DOE OSTI2021

APS: High-Energy X-rays Expediting Applied and Fundamental Research

The Advanced Photon Source (APS) at Argonne National Laboratory (ANL) was designed and built as one of the first large 3rd generation synchrotrons operated at 7 GeV. The United States Department of Energy (DOE) Office of Science funded the construction and continues to fund the operation of this national facility. Furthermore, the beamlines were originally operated by Collaborative Access Teams (CAT), which allowed a strong involvement of research institutes, universities, and industry. Today 43 of 68 beamlines are operated by the X-ray Science Division (XSD) and 35 beamlines are directly funded by the DOE Office of Science. The APS became operational in 1995, and was planned right from the beginning with 4 beamlines dedicated to high-energy x-rays above 40 keV: 1-ID designed to study engineering materials science, 6-ID-D for magnetism and condensed matter research, 11-ID-B dedicated to magnetic Compton scattering using an Elliptical Multipole Wiggler, and 11-ID-C for materials science and condensed matter physics. These stations were later joined by the bending magnet beamlines 6-BM for white beam studies and 17-BM for rapid powder diffraction. CAT operated beamlines such as 15-ID for crystallography or 16-ID for high-pressure studies also use the high-energy x-ray regime frequently. The program in Compton scattering ended in 2004 and the wiggler was replaced by an undulator. 11-ID-B became the first dedicated station for Pair Distribution Function (PDF) Analysis.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS1994

Conformational Characteristics of Poly(tetrafluoroethylene) (PTFE) Based Upon Ab Initio Electronic Structure Calculations on Model Molecules

Conformational energy contours of perfluoroalkanes, determined from ab initio calculations, confirm the well-known spitting of trans states into two minima at plus or minus 17 degrees but also show that the gauche states split as well, with minima at plus or minus 124 degrees and plus or minus 84 in order to relieve steric crowding. The directions of such split distortions from the perfectly staggered states are strongly coupled for adjacent pairs of bonds in a manner identical to the intradyad pair for poly (isobutylene) chains. These conformational characteristics are fully represented by a six-state rotational isomeric state (RIS) model for PTFE comprised of t(+), t(-), g(sup +)+, g(sup +)-, g(sup -) + and g(sup -)-states, located at the split energy minima. The resultant 6 x 6 statistical weight matrix is described by first-order interaction parameters for the g+(+) (ca. 0.6 kcal/mol) and g+- (ca. 2.0 kcal/mol) states, and second order parameters for the g(sup +)+g(sup +)+ (ca 0.6 kcal/mol) and g(sup +)+g(sup -)+ (ca. 1.0 kcal/mol) states. This six-state RIS model, without adjustment of the geometric or energy parameters as determined from the ab initio calculations, predicts the unperturbed chain dimensions and the fraction of gauche bonds as a function of temperature for PTFE in good agreement with available experimental values.

Smith, Grant D.↗
DOE OSTI2021

Resonance-Enhanced Multiphoton Ionization in the X-Ray Regime

In this work, we report on the nonlinear ionization of argon atoms in the short wavelength regime using ultraintense x rays from the European XFEL. After sequential multiphoton ionization, high charge states are obtained. For photon energies that are insufficient to directly ionize a 1s electron, a different mechanism is required to obtain ionization to Ar 17+ . We propose this occurs through a two-color process where the second harmonic of the FEL pulse resonantly excites the system via a 1s→2p transition followed by ionization by the fundamental FEL pulse, which is a type of x-ray resonance-enhanced multiphoton ionization (REMPI). This resonant phenomenon occurs not only for Ar 16+ , but also through lower charge states, where multiple ionization competes with decay lifetimes, making x-ray REMPI distinctive from conventional REMPI. With the aid of state-of-the-art theoretical calculations, we explain the effects of x-ray REMPI on the relevant ion yields and spectral profile.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2020

2020 Exascale Computing Project Annual Meeting (Executive Summary Report)

The Exascale Computing Project (ECP) delivers specific applications, software products, and outcomes on DOE computing facilities. Integration across these elements for specific hardware technologies for exascale system instantiations is fundamental to ECP success. The outcome of the ECP is the delivery of a capable exascale computing ecosystem to provide breakthrough solutions addressing our most critical challenges in scientific discovery, energy assurance, economic competitiveness, and national security. This outcome is not a matter of ensuring more powerful computing systems. The ECP is designed to create more valuable and rapid insights from a wide variety of applications (“capable”), which requires a much higher level of inherent efficacy in all methods, software tools, and ECP-enabled computing technologies to be acquired by DOE laboratories (“ecosystem”). The ECP annual meeting provides a unique opportunity for the core technical expertise in the United States focused on achieving this next plateau of computational science and computing performance to engage in direct discussions on project execution. Face-to-face gatherings in technical communities like this are common and needed for the exchange of scientific ideas and technical performance. The ECP annual meeting stands apart from other technical conferences and meetings in the computing community as it is uniquely and solely focused on the execution of the ECP and the integration of technical activities leading to the creation of the exascale computing ecosystem for the future. The direct interaction of key critical technical staff, who are leaders in their respective fields, and the resulting give-and-take between software, applications, and hardware and the technical co-design therein, is unique and essential to the effective execution of the ECP. The first annual meeting was held in Knoxville, Tennessee, January 31 – February 2, 2017 and brought together, for the first time, a diverse collection of researchers from 16 DOE national laboratories as well as university computer and computational science researchers to discuss shared problems and joint solutions for the development of a capable exascale computing ecosystem. These interactions resulted in focused technical plans and an energized community centered on advances for ECP. The second annual meeting was held in Knoxville, Tennessee, February 5–9, 2018. It included 643 individual thought leaders and performers in application development, software research and deployment, and hardware research and integrators, all of whom are part of the multifaceted, billion dollar HPC community. This meeting provided a platform to discuss and disseminate numerous examples where researchers with common goals and synergistic solutions came together for the first time to deliver tangible results. Additionally, at the 2018 meeting, ECP researchers had the opportunity to digest all US HPC vendor R&D product roadmaps pointing to exascale – not only to learn how their research can play a role, but, more importantly, to influence those roadmaps to ensure successful delivery on DOE applications that will contribute to (if not solve) problems of national interest in national security, science, energy, and health, as well as growing security threats. The third annual meeting was held in Houston, Texas, January 14–17, 2019. With a 19% increase in the number of registrations (768 people), and the change in location, the third annual meeting was considered the most impactful of the three at the time. The new website provided a better platform for the dissemination of the content, the new venue as a meeting hotel instead of a conference center facilitated interactions and discussions after event hours, and the addition of an award-winning mobile event conference app (Whova) transformed dramatically the attendee experience at the event. This fourth annual meeting was held in Houston, Texas, February 3-7, 2020. This meeting had an increase in the number of attendees for a total of 824 people registered (782 attendees) and included numerous enhancements based on feedback and lessons learned from previous meetings, some of which are listed here: Improved quality of the sessions, their material and the whole program.; Had more industry participation and addition of external collaborators from overseas.; Published the full agenda earlier to better accommodate attendance and travel plans based on schedule.; Centralized all sessions in one venue.; Provided additional hotels and room blocks for the attendees.; Improved communication with the audience (links, material, directions, notifications, etc.) to go paperless.; Enhanced side meeting scheduling, management and user experience.; Made available additional space and tables for impromptu meetings and side discussions.; Improved IT and A/V solutions for speakers. In addition, our final survey captured the following points as opportunities for improvement in future meetings: consider a different meeting location that is more pedestrian friendly, reduce talks during working meals to allow more collaboration and informal time, adapt the agenda to acknowledge attendees from different timezones, consider recording some of the tutorials and/or sessions to share broadly with the HPC community, have a larger poster room, provide additional power strips, and improve the WiFi.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2021

Hydrothermal Liquefaction: Path to Sustainable Aviation Fuel

A variety of technologies are currently under development for producing sustainable aviation fuel (SAF), and one of the most promising technologies is the hydrothermal liquefaction (HTL) of low-cost waste feedstocks. Organizations across the globe are conducting research and development on HTL technology at scales varying from the laboratory to demonstrations focused on various aspects of technology development. The identification of more advanced and sustainable solutions to maximize the fuel yield while optimizing fuel properties and achieving cost parity with conventional fuels is the major focus in developing HTL technology. This workshop on the application of HTL to produce SAF, coordinated by the U.S. Department of Energy Bioenergy Technologies Office, Commercial Aviation Alternative Fuels Initiative, and Pacific Northwest National Laboratory (PNNL), was held virtually on November 17–19, 2020. A broad spectrum of experts from industry, academia, national laboratories, and government from across the globe participated in the workshop, contributing their ideas, insights, and perspectives. A series of keynote presentations, plenary presentations, and breakout sessions provided an interdisciplinary framework for sharing information and building collaboration. This document provides an overview of the content discussed in the presentations as well as the breakout session discussion. Diverse stakeholder perspectives were gathered, and this wealth of information collectively provides an update on the current state of the field and identifies the key research opportunities.

09 BIOMASS FUELS↗
DOE OSTI2026

Aggregation and Grid Security Workshop Report

The Aggregation and Grid Security Workshop - held on June 17-18, 2025, National Laboratory of the Rockies (NLR) in Golden, Colorado - brought together approximately 40 external stakeholders from the energy sector, including VPP owner/operators, aggregators, OEMs, utilities, testing & certification labs, trade associations, and cybersecurity vendors. Led by key facilitators, the workshop focused on addressing cybersecurity challenges and enhancing grid resilience for aggregated Distributed Energy Resources (DERs) and Virtual Power Plants (VPPs). The workshop was catalyzed by recognition that traditional, rearward-looking regulatory frameworks are insufficient to keep pace with technological change. There is a "missing understanding" of risk, an "absent security basis" for managing it, and an "untenable responsibility" due to unclear ownership and requirements. The workshop aimed to shift the mindset from reacting to past crises to proactively preparing for emerging threats, fostering forward resilience through risk simulation and collaborative action. This report summarizes the outcomes of the workshop, marking it a significant step toward a secure, reliable and affordable energy future.

14 SOLAR ENERGY↗
DOE OSTI2025

Producing High-fidelity Synthetic Population Ensembles at Scale

Used within social simulations, synthetic population ensembles enable uncertainty quantification (UQ) methods for obtaining more robust model inference and prediction. A synthetic population ensemble is a series of plausible virtual reconstructions of an area’s population at the granularity of people and residences, generated stochastically to preserve privacy of the source population survey’s respondents. In this paper, we demonstrate the production of large synthetic population ensembles for the US via Oak Ridge National Laboratory’s UrbanPop framework to support modeling of high spatial resolution energy affordability metrics from nationwide social surveys in collaboration with the fusionACS project. Our initial task involves creating ensembles for 17 US metropolitan areas, each consisting of 41 population instances (a base realization and 40 replicates). To accomplish this task at scale, we configured an integrated system comprised of a research cloud, virtual containerization, GPU-enhanced functionality, and a dual API/CLI to interact with UrbanPop’s maturing Likeness Python ecosystem. We observe a reduction in theoretical execution time while maintaining high-fidelity approximations of residential totals by metropolitan area and the demographic characteristics of neighborhoods. We discuss expansion of our approach to produce synthetic population ensembles for the entire US, particularly plans to establish automated workflows for job orchestration to increase computational efficiency, as well as provide outlook for broadening applications of the ensembles.

Gaboardi, James [ORNL] (ORCID:0000000247766826)↗
NASA NTRS1976

Biostack 3 experiment MA-107

The Biostack III experiment onboard the Apollo spacecraft during the Apollo Soyuz Test Project complemented the Biostack I and II experiments of the Apollo 16 and 17 missions. The objectives of these experiments were to study the biological effects of individual heavy cosmic particles of high energy loss (HZE) not available on earth, to study the influence of additional space flight factors, to obtain knowledge on the mechanism by which HZE particles damage biological materials, to get information on the spectrum of charge and energy of the cosmic ions in the spacecraft, and to estimate the radiation hazards to man in space.

H. Bucker↗
NASA NTRS1977

Solar power satellite concepts and potential related space systems

Recent parametric studies of alternate SPS design concepts have shown that the concept appears technically feasible. The parametric studies were based on the use of advanced technology silicon solar cells for solar energy conversion. Solar array blanket unit masses of 0.31 to 0.46 kg/sq m were investigated. Conversion efficiencies of 15 to 17 percent air mass zero (AMO at 247 K) with a concentration ratio of two were considered. The systems were sized for a ground power output of 10 GW. To the level of detail studied, no design or operational problems were encountered that did not appear amenable to solution; however, the economic viability of the SPS concepts studied is obviously dependent upon a combination of technology advancement and/or the costs of competitive sources.

Redding, T. E.↗
NASA NTRS1995

The effect of plasma heating on sublimation-driven flow in Io's atmosphere

The atmospheric flow on Io is numerically computed in a flat 2-D axisymmetric geometry for a sublimation atmosphere on the trailing hemisphere subjected to plasma bombardment, UV heating, and IR cooling. Calculations are performed for subsolar vapor pressures of approximately 6.5 x 10(exp -3) Pa (approximately 3 x 10(exp 18) SO2/sq cm) and 6.8 x 10(exp -4) Pa (approximately 4 x 10(exp 17) SO2/sq cm); the latter approximates the vapor pressure of F. P. Fanale et al. (1982). The amount of plasma energy deposited in the atmosphere is 20% of the plasma flow energy due to corotation (J. A. Linker et al., 1988). It is found that plasma heating significantly inflates the upper atmosphere, increasing both the exobase altitude and the amount of surface covered by more than an exospheric column of gas. This in turn controls the supply of the Io plasma torus (M. A. McGrath and R. E. Johnson, 1987). The horizontal flow of mass and energy is also important in determining the exobase altitude; and it is shown that IR cooling can be important, although our use of the equilibrium, cool-to-space approximation for a pure SO2 gas (E. Lellouch et al., 1992) may overestimate this effect. The calculated exobase altitudes are somewhat lower than those suggested by McGrath and Johnson (1987) for supplying the torus, indicating the details of the plasma energy deposition and sputter ejection rate near the exobase, as well as the IR emission from this region need to be examined. In addition, the molecules sublimed (or sputtered) from the surface are transported to the exobase in times short compared to the molecular photodissociation time. Therefore, the exobase is dominated by molecular species and the exobase is supplied by a small region of the surface.

Wong, Mau C.↗
NASA NTRS1996

Assessment of Climate Variability of the Greenland Ice Sheet: Integration of In Situ and Satellite Data

The proposed research involves the application of multispectral satellite data in combination with ground truth measurements to monitor surface properties of the Greenland Ice Sheet which are essential for describing the energy and mass of the ice sheet. Several key components of the energy balance are parameterized using satellite data and in situ measurements. The analysis has been done for a 6 to 17 year time period in order to analyze the seasonal and interannual variations of the surface processes and the climatology. Our goal was to investigate to what accuracy and over what geographic areas large scale snow properties and radiative fluxes can be derived based upon a combination of available remote sensing and meteorological data sets. For the understanding of the surface processes a field program was designed to collect information on spectral albedo, specular reflectance, soot content, grain size and the physical properties of different snow types. Further, the radiative and turbulent fluxes at the ice/snow surface were monitored for the parameterization and interpretation of the satellite data. Highlights include AVHRR time series and surface based radiation measurements, passive microwave time series, and geodetic results from the ETH/CU camp.

Steffen, K.↗