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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 577 records · Page 32
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Design and Operation of Energy Systems with Large Amounts of Variable Generation: IEA Wind TCP Task 25 (Final Summary Report)

This report summarizes findings on wind integration from the 17 countries or sponsors participating in the International Energy Agency Wind Technology Collaboration Program (IEA Wind TCP) Task 25 from 2006-2020. Both real experience and studies are reported. Many wind integration studies incorporate solar energy, and most of the results discussed here are valid for other variable renewables in addition to wind. The national case studies address several impacts of wind power on electric power systems. In this report, they are grouped under long-term planning issues and short-term operational impacts. Long-term planning issues include grid planning and capacity adequacy. Short-term operational impacts include reliability, stability, reserves, and maximizing the value of wind in operational timescales (balancing related issues). The first section presents the variability and uncertainty of power system-wide wind power, and the last section presents recent studies toward 100% shares of renewables. The appendix provides a summary of ongoing research in the national projects contributing to Task 25 for 2021-2024. The design and operation of power and energy systems is an evolving field. As ambitious targets toward net-zero carbon energy systems are announced globally, many scenarios are being made regarding how to reach these future decarbonized energy systems, most of them involving large amounts of variable renewables, mainly wind and solar energy. The secure operation of power systems is increasingly challenging, and the impacts of variable renewables, new electrification loads together with increased distribution system resources will lead to somewhat different challenges for different systems. Tools and methods to study future power and energy systems also need to evolve, and both short-term operational aspects (such as power system stability) and long-term aspects (such as resource adequacy) will probably see new paradigms of operation and design. The experience of operating and planning systems with large amounts of variable generation is accumulating, and research to tackle the challenges of inverter-based, nonsynchronous generation is on the way. Energy transition and digitalization also bring new flexibility opportunities, both short and long term.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2023

South Africa: Framework for Energy Efficiency Demand Side Management

In July 2022, President Cyril Ramaphosa announced an emergency response plan to address the growing electricity crisis in South Africa, which included the necessity for customers of Eskom, South Africa’s primary electricity supplier, to implement demand-side energy efficiency measures. This report is the second of two reports that provides the foundation for a strategic Demand-Side Management (DSM) approach to reduce load shedding and maximize energy savings in South Africa, though inter-governmental collaboration and increased coordination of energy efficiency activities. The first report focuses on the experience of Eskom’s rate-funded Integrated Demand Management (IDM) programme, from its beginning in 2004 to today, highlighting the factors that led to failed support for the programme. This second report focuses on addressing the challenges identified in the first report and describes the elements of a policy framework to develop a sustained DSM program to meet the government’s energy efficiency goals in terms of greenhouse gas emissions reduction and social equity and inclusion to achieve a just transition.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2023

South Africa: Energy Efficiency Demand Side Management Experience (2004-2022)

In July 2022, President Cyril Ramaphosa announced an emergency response plan to address the growing electricity crisis in South Africa, which included the necessity for customers of Eskom, South Africa’s primary electricity supplier, to implement demand-side energy efficiency measures. This report is the first of two reports that provides the foundation for a strategic Demand-Side Management (DSM) approach to reduce load shedding and maximize energy savings in South Africa, through inter-governmental collaboration and increased coordination of energy efficiency activities. This first report focuses on the experience of Eskom’s rate-funded Integrated Demand Management (IDM) programme, from its beginning in 2004 to today, highlighting the factors that led to failed support for the programme, and emphasizing the measures that will need to be addressed to meet the government’s energy efficiency (EE) goals, as well as other socio-economic and environmental priorities, such as job creation, affordability and greenhouse gas (GHG) emission reduction goals.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2022

Monte Carlo calculations of the extraction of scintillation light from cryogenic $N$-type GaAs

We report the high scintillation luminosity of n-type GaAs at 10 °K is surprising because (1) with a refractive index of 3.5, escape is inhibited by total internal reflection and (2) narrow-beam experiments at 90 °K report infrared absorption coefficients of several per cm. This paper presents Monte Carlo calculations showing that the high luminosity at 10 °K can be explained if (1) the narrow-beam absorption is almost all optical scattering and (2) the absolute absorption coefficient is below 0.1 per cm. Sixteen surface reflector configurations are simulated for a range of internal scattering and absolute absorption coefficients, and these can guide the design of cryogenic scintillating GaAs targets for the direct detection of dark matter. The discussion section presents a possible infrared scattering mechanism based on the metallic nature of n-type GaAs. A supplement file describes (1) the Monte Carlo program steps in detail and (2) how narrow-beam and integrating sphere experiments can measure the cryogenic optical scattering and absolute absorption coefficients.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2022

Tungsten doped diamond shells for record neutron yield inertial confinement fusion experiments at the National Ignition Facility

We report on fabrication and characterization of layered, tungsten doped, spherical about 2 mm diameter microcrystalline diamond ablator shells for inertial confinement fusion (ICF) experiments at the National Ignition Facility. As previously reported, diamond ICF ablator shells can be fabricated by chemical vapor deposition (CVD) on solid spherical silicon mandrels using an ellipsoidal microwave plasma reactor. In the present work, we further developed these ablator shells by embedding a W -doped diamond layer sandwiched between two undoped diamond regions. W incorporation in diamond was achieved by adding tungsten hexacarbonyl to the CH 4 /H 2 CVD feed gas. We observe that the W doping concentration decreases with increasing deposition rate which, in turn, is controlled by adjusting the total gas pressure. Cross sectional microstructural analysis reveals sharp interfaces between doped and undoped regions of the diamond shell and uniform W distribution with concentrations up to about 0.3 at.%. At higher W concentrations (>0.3 at.%) formation of tungsten carbide precipitates is observed. Using a 3-shock 1.6 MJ laser pulse, the targets described in this work produced the first laser driven implosion to break the 1 × 10 16 neutron yield barrier, followed by experiments (described in future publications) with similar targets and slightly more laser energy producing yields as high as 4 × 10 17 .

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Investigating User Experiences with Data Abstractions on High Performance Computing Systems

Scientific exploration generates expanding volumes of data that commonly require High Performance Computing (HPC) systems to facilitate research. HPC systems are complex ecosystems of hardware and software that frequently are not user friendly. The Usable Data Abstractions (UDA) project set out to build usable software for scientific workflows in HPC environments by undertaking multiple rounds of qualitative user research. Qualitative research investigates how individuals accomplish their work and our interview-based study surfaced a variety of insights about the experiences of working in and with HPC ecosystems. This report examines multiple facets to the experiences of scientists and developers using and supporting HPC systems. We discuss how stakeholders grasp the design and configuration of these systems, the impacts of abstraction layers on their ability to successfully do work, and the varied perceptions of time that shape this work. Examining the adoption of the Cori HPC at NERSC we explore the anticipations and lived experiences of users interacting with this system’s novel storage feature, the Burst Buffer. We present lessons learned from across these insights to illustrate just some of the challenges HPC facilities and their stakeholders need to account for when procuring and supporting these essential scientific resources to ensure their usability and utility to a variety of scientific practices.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2022

Liquid Argon Time Projection Chamber Trigger Development with MicroBooNE

The Micro Booster Neutrino Experiment (MicroBooNE) is a Liquid Argon Time Projection Chamber (LArTPC) neutrino detector at Fermilab that has been operating since 2015. It aims to perform v-Ar cross-section measurements, explore the low-energy excess reported by the MiniBooNE experiment and perform a combined search for sterile neutrino oscillations as part of three LArTPCs that make up the Short Baseline Neutrino (SBN) Program at Fermilab. Since MicroBooNE is currently in an R&D phase, it offers a unique opportunity for the implementation and testing of TPC-based triggers as R&D towards the Deep Underground Neutrino Experiment (DUNE). One of the technical challenges of DUNE that we aim to address with this study is that of efficient self-triggering of a LArTPC utilizing TPC signal information. This capability will enable searches for rare processes in DUNE, such as neutrino interactions from a potential galactic supernova burst. This talk will describe the MicroBooNE TPC readout system and ongoing R&D efforts to develop and demonstrate TPC-based triggering.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2025

Neutron Fluence and Kerma Responses to Bare, Steel-Reflected, and Lucite-Reflected Steady-State Operations of the ORNL Health Physics Research Reactor

The experiments evaluated in this report were conducted at the Health Physics Research Reactor (HPRR), also known as the Fast Burst Reactor. The reactor was designed and built at Oak Ridge National Laboratory (ORNL) in 1961. In this evaluation, a total of 12 experiments were evaluated (6 shield configurations and two responses). Six of them are considered acceptable as benchmark experiments and are thoroughly described: the measurands are bare, steel-shielded and Lucite-shielded neutron fluences and neutron KERMA responses to steady-state operations of the HPRR. It is important to mention that there is a general lack of information in the experimental methodology and neutron spectrum unfolding, and in some cases, unexpected and unexplained discrepancies between calculation and experiment. The HPRR’s unique characteristics were that it is a fast reactor, the use of a Lucite shield as the shielding material, and the use of the neutron fluence as the main benchmark measurand. There are no known, significant correlations between benchmarks in this evaluation and benchmarks in other evaluations.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2026

NRC Reactor Operating Experience Analysis and Trend Summary: 2024 Update

This report presents a summary of the Nuclear Regulatory Commission’s (NRC’s) reactor operating experience analyses with data through 2024 as well as the reliability and frequency trends identified in the 2024 update reports for the component performance studies, loss-of-offsite power analysis, initiating events analysis, and system studies provided on the NRC Reactor Operating Experience Results and Databases website (https://nrcoe.inl.gov/).

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2023

Connecting mechanical properties to hydrogen defects in PAN-based carbon fibers

Atomic-level defects dictate the mechanical properties of carbon fibers and strong correlations have been established between the crystallite sizes and mechanical properties. We recently demonstrated similar correlations with hydrogen content, but reliably quantifying the hydrogen content is not possible using only inelastic neutron scattering experiments. Here, we present prompt-gamma activation analysis (PGAA) experiments collected on 20 commercially available carbon fibers to quantify the hydrogen content of carbon fibers and find correlations between fiber modulus and hydrogen content. We then evaluate the role of hydrogen defect type and connect the PGAA results to both newly acquired and recently reported inelastic neutron scattering experiments. In conclusion, we find that intercalated hydrogen defects are preferentially removed at carbonization temperatures required for high-modulus fibers, potentially giving rise to voids within the carbon fibers that undermine their tensile strength.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Methods for Rotating Electrodes in High-Temperature Molten Salts

Abstract In this paper, we describe and validate a custom apparatus for performing high-speed (250-3,500 rpm) rotating electrode and dilatometer density experiments in molten salts. The reported details can aid in decreasing the difficulty and increasing the quality of such experiments. We discuss the design challenges and the solutions identified. We investigate methods for accurately measuring the solution resistance using electrochemical impedance spectroscopy, calculating the working electrode area using cyclic voltammetry, and measuring the mass transfer-limited current of rotating electrodes using a series of chronoamperometry pulses. We further demonstrate the efficacy of our methods in producing accurate results.

Fuller, Ranon (ORCID:0000000255400197)↗
DOE OSTI2019

Intrinsic charm production of doubly charmed baryons: Collider vs. fixed-target

We report the LHCb Collaboration has measured the doubly charmed baryon, $\Xi^{++}_{cc} (ucc)$, through two different decay channels in $p + p$ collisions at center-of-mass energies of 7, 8 and 13 TeV. While they have performed similar searches for the doubly charmed baryon $\Xi^{+}_{cc} (dcc)$, it has not yet been observed by LHCb. However, the fixed-target experiment, SELEX, at Fermilab, reported the observation of the $\Xi^{+}_{cc}$ in two different decay channels with a 600 GeV charged hyperon beam. The beam was composed of an admixture of $π^{±}, p, \overline p $ components as well as the $Σ^–$ hyperon. Much discussion has arisen over the fact that the fixed-target observations have not been easily reproduced by the collider experiments at higher energies, where one might have expected the production rates to be much higher due to the orders of magnitude increase in the center of mass energy with LHCb.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2026

Resonance Ionization Spectroscopy Experiment at Facility for Rare Isotope Beams

This manuscript reports on the commissioning of the Resonance Ionization Spectroscopy Experiment (RISE) at the BEam COoler and LAser spectroscopy (BECOLA) facility at Facility for Rare Isotope Beams (FRIB). The instrument implements the collinear resonance ionization spectroscopy technique for sensitive measurements of isotope shifts and hyperfine structure of short-lived isotopes produced at FRIB. The existing BECOLA beamline was extended to integrate an electrostatic ion-beam bender and an ion detector at ultrahigh vacuum. An injection-seeded titanium-sapphire laser and a multiharmonic pulsed neodymium-doped yttrium aluminum garnet laser were installed to perform resonant excitation and selective ionization. Commissioning tests were performed to demonstrate the capabilities of the instrument by measuring the hyperfine structure of stable 27 Al produced in an offline ion source. The RISE instrument is ready and operational for future studies of short-lived isotopes at FRIB.

Atomic spectra↗
DOE OSTI2023

TEX-Hf: Integral Experiment Execution of Thermal/Epithermal eXperiments using Highly Enriched Uranium with Polyethylene and Hafnium (IER-532 CED-3b Report)

This report documents the experimental configurations and measurements for IER-532, Thermal/Epithermal eXperiments (TEX) with highly enriched uranium (HEU) fuel and interstitial hafnium (Hf), moderated and reflected by polyethylene. TEX-Hf is a variation of and based on the TEX-HEU (IER-297) design, with the inclusion of hafnium. These configurations provide integral experiments for validation of hafnium in the thermal, intermediate, and fast neutron energy regimes by maximizing the sensitivity in k eff to the hafnium isotope cross sections. The experiment campaign was completed over seven weeks during the end of FY22 and beginning of FY23 at the National Critical Experiments Research Center at the Nevada National Security Site. The campaign produced seven experimental configurations, four reproducibility measurements, and many additional dimensional measurements that will be of use to the future benchmark evaluation of this experiment and other experiments using the same HEU fuel. Table 1 summarizes the TEX-Hf experimental configurations, including their physical parameters, calculated fission fractions, and estimated excess reactivities.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

Data Science and Computation for Rapid and Dynamic Compression Experiment Workflows at Experimental Facilities, September 8-11, 2020. Workshop Report

The application of high pressure to materials has enabled discoveries in scientific fields such as planetary science, materials science, and materials synthesis. Recent advances in X-ray user light sources and other facilities, co-location and integration of user facilities with high-pressure drivers, availability of high-performance computing (HPC) platforms, and the development of new data science techniques have created opportunities for, and challenges in, advancing data analytics for rapid and dynamic compression experiments. To address these challenges, harness the emerging technology now available, and expedite scientific discovery, Los Alamos National Laboratory (LANL) hosted a virtual workshop entitled “Data Science and Computation for Rapid and Dynamic Compression Workflows at Experimental Facilities” from September 8 to 11, 2020. The workshop included 95 registered scientists and analytics experts from 15 universities, 9 United States (US) national laboratories, 5 US and European X-ray light sources, neutron sources such as the Los Alamos Neutron Science Center (LANSCE), other big science facilities such as the National Ignition Facility (NIF), and an industry representative. The workshop included 31 invited talks and 4 lightning talks by students and postdocs.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Shock compression response of an insensitive high explosive single crystal: 1,1-diamino-2,2-dinitroethene (FOX-7)

Insensitive high explosives (IHEs) – that do not compromise performance – are of immense interest as a safer alternative to conventional high explosives, such as pentaerythritol tetranitrate (PETN) and cyclotrimethylenetrinitramine (RDX). Despite the strong interest in using IHEs, shock compression experiments on IHE single crystals have not been reported. To address this need, plate impact experiments were conducted to measure wave profiles in 1,1-diamino-2,2-dinitroethene (FOX-7) single crystals – a representative IHE crystal – shocked to 21 GPa longitudinal stress. Particle velocity histories, measured using laser interferometry, show a clear two-wave structure (elastic-inelastic response) at modest stresses (<3.8 GPa). Wave profiles at higher stresses show a single (overdriven) wave. Measured shock velocities and wave profiles provide accurate Hugoniot data to 21 GPa. The measured wave profiles to 21 GPa show no sign of energy release due to chemical decomposition and constitute the first demonstration of an IHE single crystal insensitivity under plane shock compression. Numerical simulations using a phenomenological material model developed for FOX-7 showed good agreement with the measured wave profiles. The experimental results and continuum simulations presented here constitute a significant first step in gaining insight into the shock compression response of IHE single crystals.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2022

Shocked silica aerogel radiance transition

Silica (SiO 2 ) aerogel is widely used in high-energy-density shock experiments due to its low and adjustable density. Reported here are measurements of the shock velocity, optical radiance, and reflectivity of shocked SiO 2 aerogel with initial densities of 0.1, 0.2, and 0.3 g/cm 3 . These results are compared with similar data from three solid polymorphs of SiO 2 , silica, quartz, and stishovite with initial densities 2.2, 2.65, and 4.3 g/cm 3 , respectively. Interestingly, below a brightness temperature of T bright ≈ 35,000 K, the slope of the radiance vs shock velocity is the same for each of the SiO 2 aerogels and solid polymorphs. At T bright ≈ 35000 K, there is an abrupt change in the radiance vs shock velocity slope for aerogels, but not seen in the solid polymorphs over the pressures and temperatures explored here. An empirical model of shock front radiance as a function of SiO 2 density and laser drive parameters is reported to aid in the design of experiments requiring maximum shock front radiance.

42 ENGINEERING↗
DOE OSTI2021

Low Temperature Time-to-Explosion Experiments on HMX in the LLNL's ODTX/P-ODTX System (FY 2020 Annual Report)

Over the last few decades, there has been a considerable research effort on the thermal decomposition and thermal explosion violence of energetic materials at elevated temperatures in different sample geometries and confinements. Thermal explosion studies on various energetic materials in two-dimensional geometry such as the Scaled-Thermal-Explosion-Experiment (STEX) system and the Sandia-Instrumented-Thermal-Ignition (SITI) system have been reported. The One-Dimensional Time to Explosion (ODTX) system, designed and built by LLNL, has been used since 1970s for thermal explosion studies. The system is attractive because of the one-dimensional geometry and minimal sample requirement. With the recent integration of a pressure monitoring element, the system can study pressure behavior of materials subjected to and during thermal exposure. Rapid pressure monitoring in µsec intervals allow for enhanced pressure determination in the time right before thermal explosion. The test data can be used for the validation of existing thermal models, particularly for introducing pressure terms. This report summarizes the efforts in performing small-scale safety tests, particle size measurements and conducting 7 ODTX/P-ODTX experiments on the Cl5 HMX material that Hunting uses for oil field applications.

36 MATERIALS SCIENCE↗