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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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All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Overview and status of the Long Baseline Neutrino Facility cryogenics system

The Long Baseline Neutrino Facility (LBNF) serves to provide the infrastructure necessary to support the Deep Underground Neutrino Experiment (DUNE), a growing international experiment to study neutrino science and proton decay. Situated at the Sanford Underground Research Facility (SURF), in Lead, SD, USA, DUNE will employ detectors located within massive cryostats filled with a total of 68,400 tons of ultrapure liquid argon. LBNF provides the cryogenic infrastructure necessary to supply and maintain that argon throughout the life of DUNE, as it enables the study of neutrinos from a new and improved beamline from Fermilab, as well as the dynamics of supernovae responsible for producing the heavy elements necessary for life and the possibility of proton decay. This contribution presents the modes of operation, layout, and main features of the cryogenic systems at LBNF. Those systems expected performance, functional requirements, and overall design status is also featured.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Numerical modeling of a proof-of-principle experiment on optical stochastic cooling at an electron storage ring

Cooling of beams circulating in storage rings is critical for many applications including particle colliders and synchrotron light sources. A method enabling unprecedented beam-cooling rates, optical stochastic cooling (OSC), was recently demonstrated in the Integrable Optics Test Accelerator (IOTA) electron storage ring at Fermilab [J. Jarvis , ]. This paper describes the numerical implementation of the OSC process in the particle-tracking program and discusses the validation of the developed model with available experimental data. The model is also employed to highlight some features associated with different modes of operation of OSC. The developed simulation tool should be valuable in guiding future configurations of optical stochastic cooling and, more broadly, modeling self-field-based beam manipulations. Published by the American Physical Society 2024

43 PARTICLE ACCELERATORS↗
DOE OSTI2019

Nonlinearity in the Dark: Broadband Terahertz Generation with Extremely High Efficiency

Plasmonic metamaterials and metasurfaces offer new opportunities in developing high performance terahertz emitters and detectors beyond the limitations of conventional nonlinear materials. However, simple meta-atoms for second-order nonlinear applications encounter fundamental trade-offs in the necessary symmetry breaking and local-field enhancement due to radiation damping that is inherent to the operating resonant mode and cannot be controlled separately. Here we present a novel concept that eliminates this restriction obstructing the improvement of terahertz generation efficiency in nonlinear metasurfaces based on metallic nanoresonators. This is achieved by combining a resonant dark-state metasurface, which locally drives nonlinear nanoresonators in the near field, with a specific spatial symmetry that enables destructive interference of the radiating linear moments of the nanoresonators, and perfect absorption via simultaneous electric and magnetic critical coupling of the pump radiation to the dark mode. Our proposal allows eliminating linear radiation damping, while maintaining constructive interference and effective radiation of the nonlinear components. We numerically demonstrate a giant second-order nonlinear susceptibility ~10 –11 m/V, a one order improvement compared with the previously reported split-ring-resonator metasurface, and correspondingly, a 2 orders of magnitude enhanced terahertz energy extraction should be expected with our configuration under the same conditions. Here, our study offers a paradigm of high efficiency tunable nonlinear metadevices and paves the way to revolutionary terahertz technologies and optoelectronic nanocircuitry.

42 ENGINEERING↗
DOE OSTI2018

Quench Detection for High-Temperature Superconductor Conductors Using Acoustic Thermometry

Detecting local heat-dissipating zones in high-temperature superconductor (HTS) magnets is a challenging task due to slow propagation of such zones in HTS conductors. For long conductor lengths, voltage-based methods may not provide a sufficient sensitivity or redundancy, and therefore nonvoltage-based detection alternatives are being sought. One of those is the recently proposed method of Eigen Frequency Thermometry (EFT), which is an active acoustic technique for a fast and nonintrusive detection of 'hot spots,' utilizing temperature dependence of the conductor elastic moduli. In this work, we demonstrate the efficiency of EFT for detecting localized heating in a 1.2-m-long sample of REBCO tape immersed in liquid nitrogen, and benchmark sensitivity of the acoustic detection with respect to voltage, hot spot temperature, and power dissipation in the conductor. Modifying the original technique for differential mode of operation enables a much improved sensitivity, and adds a hot spot localization capability. Furthermore, we adapt this technique to subscale coils wound with REBCO CORC conductor built in the framework of U.S. Magnet Development Program. A successful thermal-based detection of dissipation onset at the critical current for a two-layer canted CORC dipole assembly is discussed.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2021

Performance Testing and Assessment of Protection Scheme Using Real-Time Hardware-in-the-Loop and IEC 61850 Standard

The main challenge of the microgrid is to design a suitable protection scheme due to the complexity of the architecture of the microgrid. The importance of the proposed protection technique is threefold. First, it presents a co-simulation platform to integrate between a simulated model on power system computer aided design (PSCAD)/real time digital simulator computer aided design (RSCAD) software’s and physical devices schweitzer engineering laboratories (SEL) 421-7 relays to protect the microgrid that includes different resources connected based on inverter interface. Second, it presents a comprehensive hardware/software setup to test the protective relays in a closed loop system and shows how to configure the protective relay’s International Electrotechnical Commission 61850 communications. Third, IEEE 1588 standard is used to provide sub nanoseconds latency between the simulated model that emulated on real time digital simulator (RTDS) and the external devices. Also, the measurement signals are synchronized between RTDS and the external devices using giga-transceiver synchronization card (GTSYNC) interface card and SEL-2488 satellite-synchronized network clock. The results showed that the co-simulation infrastructure introduces a highly dependable design, analysis, and testing environment for cyber and physical data flow in the system. Besides that, the voltages at ac/dc sides and frequency at fault condition were maintained due to the energy storage device contributions at different modes of operation.

42 ENGINEERING↗
DOE OSTI2019

Influence of Time-of-Flight Chromatic Aberration on the Dynamics of Propagation of Pulsed Electron Beam in Ultrafast Electron Microscopy: A New Strategy for Better Temporal Resolution

A common strategy aimed at achieving a high temporal resolution in ultrafast electron microscopy and diffraction is based on the use of strong electrostatic fields in the accelerating gap to form fast electron pulses of ultrashort duration. In this work, the dynamics of the propagation of ultrashort photoelectron bunches is studied taking into account the time-of-flight chromatic aberration: the spread-out of electron pulses at the exit from the region of the accelerating electric field. The results of the calculation of the duration of photoelectron pulses taking into account Coulomb repulsion are presented. According to the analysis, the use of strong electrostatic fields in the accelerating gap for the formation of fast electron pulses of ultrashort duration is not a necessary condition for achieving the final high temporal resolution in the method of ultrafast electron microscopy. The modes of operation of ultrafast transmission electron microscope were found for which the temporal resolution increases with the growth of time-of-flight chromatic aberration.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2022

Perspective—Potential Benefit of Li-Rich Cathode Materials: Reduction of Co and Ni Content Rather than Achievement of Ultra-High Capacities

In the conventional cycling protocol for lithium and manganese rich NMC layered oxides (LMRNMC), the upper cutoff voltage V cut is extended to ~ 4.8, to achieve capacities of similar to 250 mAh g -1 . With this mode of operation, structural rearrangements result in voltage fade upon cycling. Herein, a strategy is proposed to avoid these structural rearrangements based on (a) restricting V cut to values < ~ 4.6 to shut down the bulk instabilities, and (b) application of a (preferably) semi-coherent coating that protects the surface oxygen. The potential benefit of this strategy would be to minimize Co and Ni content, compared to Ni-rich NMC.

25 ENERGY STORAGE↗
DOE OSTI2019

Evaluation and Specifications for In-Line Uranium Separations Using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) Detection for Trace Elemental Analysis

Automated introduction platforms integrated with inductively coupled plasma optical emission spectroscopy (ICP-OES) systems are continuously being improved. Expanding on the introduction systems, a newly developed automated ion chromatography system was explored for performing rapid in-line separations coupled to ICP-OES for the detection of trace elements in uranium. Trace elements are separated from a uranium material and the analytes are directed into the ICP-OES for subsequent detection. Detection parameters such as exposure time frequency, wavelength selection, and settling times were explored to gain insight on optimal detection schemes for in-line trace elemental analysis. The methodology was applied in the analysis of a uranium oxide (U3O8) certified reference material, CRM-124. It was found here that the sensitivity and uncertainty of the technique are greatly affected by how the ICP-OES is employed to collect data. Overall it was determined that faster exposure replicates can provide greater peak resolution with higher fidelity measurements but are limited with respect to the total analysis time (i.e., limited in detection timely separations). In conclusion zeta scores, which combine accuracy and uncertainty of certified values and experimental values, were used to validate the ICP-OES modes of operation.

47 OTHER INSTRUMENTATION↗
DOE OSTI2025

Nitric oxide molecular tagging velocimetry of a free-flight model in a reflected shock tunnel

Nitric oxide molecular tagging velocimetry (NO MTV) is used to characterize the wake behind a free-flight spherical model in the test section of a free-piston reflected shock tunnel using a burst-mode laser operated at 100 kHz. A novel (to our knowledge) multi-delay timing scheme was implemented to measure velocity in a varying collisional environment in the wake of the free-flight model. Four simultaneous velocity profiles were measured in the wake of the model from -600 to 3600 m/s for flow enthalpies of 10.3 and 12.0 MJ/kg. Finally, the measured velocity distributions show good agreement when compared to computational fluid dynamics (CFD) modeling.

47 OTHER INSTRUMENTATION↗
DOE OSTI2022

National Marine Renewable Energy Center Upgrades - LUPA

The data provided is part of a power take off damping optimization study. The power take off damping coefficient was swept from 0 to approximately 7000 N/m/s during a single regular wave test with a real time control of the motor/generator. The generated power from the LUPA (Lab Upgrade Point Absorber) wave energy converter is reported by the motor drive in watts. The csv files in this submission are the corresponding raw time series outputs for each mode of operation of LUPA (one body heave only, two body heave only, and two body six degrees of freedom). Data comes from testing in the Large WaveFlume (LWF) at the O.H. Hinsdale Wave Research Laboratory in Corvallis, OR.

16 TIDAL AND WAVE POWER↗
DOE OSTI2023

Development of an ERL for Coherent Electron Cooling at the Electron-Ion Collider

The Electron-Ion Collider (EIC) is currently under development of to be built at Brookhaven National Lab and requires cooling during collisions in order to preserve the quality of the hadron beam despite degradation due to intra-beam scattering and beam-beam effect. An Energy Recovery Linac (ERL) is being designed to deliver the necessary electron beam for the Coherent electron Cooling (CeC) of the hadron beam, with an electron bunch charge of 1 nC and an average current of 100 mA; two modes of operation are being developed for 150 and 55 MeV electrons, corresponding to 275 and 100 GeV protons. The injector of this SHC-ERL is shared with the Precooler ERL, which cools lower energy proton beams via bunched-beam cooling, as used in Low Energy RHIC electron Cooling (LEReC). This paper reviews the current state of the design.

Accelerator Physics↗
DOE OSTI2024

Development of an ERL for Coherent Electron Cooling at the Electron-Ion Collider

The Electron-Ion Collider (EIC) is currently under development to be built at Brookhaven National Lab and requires cooling during collisions in order to mitigate the hadron beam emittance degradation due to intra-beam scattering and beam-beam effects. An Energy Recovery Linac (ERL) is being designed to deliver the necessary electron beam for Coherent electron Cooling (CeC) of the hadron beam, with an electron bunch charge of 1 nC and an average current of 100 mA; two modes of operation are being developed for 150 and 55 MeV electrons, corresponding to 275 and 100 GeV protons. The injector of this Strong Hadron Cooler ERL (SHC-ERL) is shared with the Pre-cooler ERL, which cools lower energy proton beams via bunched beam cooling, as used in the Low Energy RHIC electron Cooling (LEReC). This paper reviews the current state of the design.

Deitrick, K.↗
DOE OSTI2018

Prototype Stilbene Neutron Collar II

A neutron collar using stilbene organic scintillator cells for fast neutron counting is described for the assay of fresh low enriched uranium (LEU) fuel assemblies. The prototype stilbene collar has a form factor similar to standard He-3 based collars and uses an AmLi interrogation neutron source. This report describes the simulation, using a custom LLNL developed MCNPX, of list mode neutron correlation data on various fuel assemblies. Some of these fuel assemblies have neutron absorbers (burnable Gd poisons) and partial defect s (DU, Fe, Pb pins). Calibration curves (doubles vs 235 U linear mass density) are presented for fast (with Cd lining) mode of operation. The modeling incorporates LLNL developed neutron crosstalk correction algorithms and stilbene light output detector response quench function. Pileup issues are addressed using the LLNL code GamGen / RadSrc to estimate the flux of alpha decay gammas from the fuel assemblies on the stilbene cells with and without Pb shielding. One panel of the prototype collar using 10 high-efficiency 4”x2” stilbene cells from Inrad Optics, using LLNL developed technology, has been constructed and calibrated for optimal PSD and data acquisition electronics. Several sources (AmLi, AmBe, Cf, DD, and DT) have been measured with the single panel and the measured data is consistent with the modeling. A novel part of our work was to determine the light output (LO) quench function for the Inrad 4” x 2” stilbene crystals through a LLNL-MCNPX simulation based optimized fitting of the measured LO data.

42 ENGINEERING↗
DOE OSTI2020

Co-op at Sandia National Laboratories (July - December 2019, Final Report)

This co-op was performed at Sandia National Laboratories (SNL) within the Weapon Surety Engineering 11 Department (9435), which is a customer-focused organization that provides engineering and system analysis expertise to ensure a safe deterrent throughout the entire weapon lifecycle. Engineers in 9435 develop a deep knowledge in both component and system function to support rigorous evaluation and mitigation of potential failure modes. They operate across multiple engineering disciplines (mechanical, electrical, computer, materials and systems engineering) with opportunities to develop crossdisciplinary capability. The team supports a variety of stockpile systems and is part of the product teams during development, design and production, as well as advanced concept and exploratory efforts. 9435 engineers use their extensive component and system knowledge, as well as experimental data and modeling, to ensure products function as intended with assured safety. Members of the department learn the function of multiple components, how those components integrate within the system and apply surety principles and processes to ensure a safe, secure, reliable, and effective U.S. nuclear deterrent.

42 ENGINEERING↗
DOE OSTI2020

System Study: Residual Heat Removal 1998–2018

This report presents an unreliability evaluation of the residual heat removal (RHR) system in two modes of operation (low-pressure injection in response to a large loss-of-coolant accident and post-trip shutdown-cooling) at 104 U.S. commercial nuclear power plants. Demand, run hours, and failure data from calendar years 1998 through 2018 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Industry Reporting and Information System (IRIS), formerly the INPO Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the RHR results.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2020

Catalytic Removal of Oxygen and Pollutants in Exhaust Gases from Pressurized Oxy-Combustors

The primary goal of this project was to develop and validate advanced catalytic materials and systems for purifying the flue gas generated from pressurized oxy-combustors in an effort to achieve the purity specifications of carbon dioxide (CO 2 ) streams required by the U.S. Department of Energy (USDOE) for application in enhanced oil recovery. The technology has shown great potential for improving energy efficiency, simplifying process complexity, and lowering costs compared with current state-of-the-art oxy-combustion flue gas purification technologies. Laboratory studies were conducted for the development, characterization, and screening of metal catalysts for residual oxygen (O 2 ) reduction with methane (CH 4 ) and multifunctional carbon catalysts for combined nitrogen oxides (NO x ), sulfur oxides (SO x ), and mercury (Hg) removal. A bench-scale reverse-flow fixed-bed (RFFB) reactor and a trickle-bed direct-contact cooler (DCC) reactor capable of treating 15 standard liters per min of pressurized oxy-combustion flue gas were fabricated and tested with both a simulated flue gas in the laboratory and a slipstream of actual flue gas at a 100 kW th Staged, Pressurized Oxy-Combustion (SPOC) pilot facility. Process simulation and techno-economic studies were performed to evaluate the energy efficiency and cost of the developed catalytic flue gas purification process integrated into a conceptual 550-MWe SPOC power plant. The goal and objectives of the project have been successfully accomplished. A cobalt-manganese (CoMn) oxide catalyst was developed and demonstrated in the bench-scale RFFB reactor in either a reverse-flow or one-direction flow mode of operation that met the success criterion of performance for residual O 2 reduction. A carbon catalyst was developed and demonstrated in the bench-scale DCC reactor that met the success criterion of performance for combined NO x /SO x /Hg removal. Slipstream testing of the integrated DCC-RFFB system at the SPOC pilot facility demonstrated stable operation and verified the superior performance obtained in the laboratory. The techno-economic analysis showed that a 550-MWe SPOC plant integrated with the catalytic flue gas purification process would result in costs of electricity of $\$$96.94/MWh and $\$$80.27/MWh in two assessed cases compared with $\$$91.07/MWh reported for the USDOE’s Current Technology Case, which generated only a partially pure CO 2 stream. On the basis of the results and findings from this project, scale-up studies of materials production and system demonstration and optimization studies of reactors and processes are recommended at the next stage of technology development.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2020

New Septum Dump Quadrupole Magnet Design

The purpose of the septum dump quadrupole (SDQ) magnet is to expand the beam size on the septum dump of the DARHT Axis 2 downstream transport in the same manner as the S2 magnet expands the beam on the beam stop for mode 1 operations of DARHT Axis 2. This is necessary in order to minimize the heating of the carbon beam dump and suppress desorption of ions. Initially, ions are generated through stimulated desorption and ionization of the monolayers of water vapor stuck to the beam dump surface. These ions propagate upstream at high speeds and act as an electrostatic focusing lens by reducing the beam space charge. As the beam size on the dump decreases, the dump is sufficiently heated so that a surface plasma is formed and much greater quantities of ions are generated through space charge limited emission. The interaction of these ions with the beam causes significant disruption of the beam.

43 PARTICLE ACCELERATORS↗
DOE OSTI2021

In Situ Machine Learning for Intelligent Data Capture on Exascale Platforms. Final Report

In many dynamic systems, interesting events occur locally in time and space. Examples of such systems include ignition events in combustion simulations, material fractures in mechanics simulations, and extreme weather events in climate simulations. Due to memory constraints and data I/O costs, current simulation workflows save data at regularly spaced time-steps, at a fixed rate determined before the start of the simulation. Often this mode of operation results in missed events of interest, necessitating a simulation restart from before an event occurred with more frequent data saves. This data saving workflow is grossly inefficient and is already a bottleneck in the computing process. We propose to develop machine learning algorithms that can detect when interesting dynamical events are occurring, triggering data saves. These machine learning algorithms will perform in situ anomaly detection to flag regions with different dynamical properties than those previously recorded. The adaptive data saves would be local in time and space to match the event of interest, thereby enabling a much more efficient workflow that will reduce data I/O costs and data storage memory requirements. The algorithms will be tested on two applications: auto-ignition simulations and climate simulations. A critical component of this project will be developing machine learning algorithms that can be deployed efficiently in situ on HPC platforms with out-of-the-box functionality. The development of in situ machine learning methods to detect anomalous events would enable a more efficient and effective workflow, in which all the relevant data are saved in a single simulation run, without re-starts or scientist intervention.

42 ENGINEERING↗

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