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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 505 records · Page 28

2017 NE-4 Nuclear Technologies Research and Development (NTRD) Achievements Report

Fiscal year (FY) 2017 initiated new and reestablished presidential and departmental nuclear energy priorities for the U.S. Department of Energy (DOE), Office of Nuclear Energy (DOE-NE) that will: • Support the Administration’s priorities to achieve U.S. energy dominance and economic prosperity through U.S. technology leadership • Support DOE-NE mission priorities and goals for the existing nuclear fleet, advanced reactor pipeline and national fuel cycle infrastructure • Focus on early stage research, and effective cooperation with industry, academia, and other government agencies • Propose investments to maintain and improve capabilities and infrastructure to conduct leading-edge science, research, and technology development. DOE-NE’s mission priorities will focus on the existing nuclear fleet, advanced reactor pipeline, and fuel cycle infrastructure. Therefore, the DOE Nuclear Technology Research and Development (NE-4) mission aligned to (1) support the research and development (R&D) of innovative reactor technologies that may offer improved safety, functionality, and affordability and (2) conduct research to reduce long-term technical barriers for advanced nuclear energy systems, including space fission systems. Key activities to execute this mission include: • To achieve the NE-4 mission priorities, two major programs with eight R&D campaigns are engaged in impactful research, development, demonstration, and deployment: Fuel Cycle Technologies (FCT) Program • Fuel Cycle Options Campaign evaluates complex fuel cycle options and provides performance metrics on various systems and scenarios to improve the knowledge of interdependencies between technologies and different systems. • Advanced Fuels Campaign performs science-based R&D on accident tolerant fuels in addition to advanced light-water reactor (LWR) fuel and transmutation fuel. • Joint Fuel Cycle Studies (JFCS) is a collaboration with the Republic of Korea to assess the feasibility and nonproliferation of electrochemical recycling to manage used fuel. • Material Recovery and Waste Form Development (MRWFD) Campaign researches advanced fuel cycle material recovery and waste management capabilities to improve fuel cycle performance with less processing and waste generation. • Material Protection, Control, and Accountability Technologies (MPACT) Program develops tools and capabilities to secure the next generation nuclear materials management and safeguards for nuclear fuel cycles. Advanced Reactor Technologies (ART) Program • Fast Reactors Campaign targets benefits in either resource utilization or waste management and possesses favorable features for small reactor applications and plutonium management. • Gas-Cooled Reactors Campaign seeks to raise the technological readiness of high temperature gas-cooled reactors (HTGRs) and other reactor concepts utilizing coated particle fuel, graphite, or helium coolant by performing high risk, enabling research and development that commercial developers are unable or unwilling to undertake in the current energy market. • ART Energy Conversion (EC) Project provides solutions to convert heat from an advanced reactor to useful products that support commercial application of the reactor designs.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Cost estimation inputs for spent nuclear fuel geologic disposal concepts (Revision 1)

A set of 16 geologic disposal concepts is described in sufficient detail for rough-order-of-magnitude repository cost estimates, for disposal of spent nuclear reactor fuel in generic crystalline, argillaceous, and salt host geologic media. The description includes total length, diameter, and volume for all underground shafts, ramps, drifts and large-diameter borings. Basic types of ground support are specified. Total repository capacity is assumed to be approximately 140,000 MT of spent fuel, but concepts are described in terms of modular panels each containing 10,000 MT. Waste packaging is described, and the materials and outer dimensions for disposal overpacks are given. The manner of emplacement is specified, with any additional fixturing, lining, buffer materials, and backfill needed. Thermal limits for waste package emplacement or repository closure are given, as appropriate for enclosed and open emplacement modes, respectively. The 16 disposal concepts are based on disposal concept studies performed for the Used Fuel Disposition R&D program between 2011 and 2014, and the accompanying engineering analyses. Revision 1 results from review and checking of repository spacings, drift length estimates, repository plan area estimates, closure power limits, and estimates of fuel age at closure.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Single-Bunch Instabilities at the Fermilab Recycler Ring

Understanding and characterizing collective instabilities is critical for high-intensity operation at the Fermilab Recycler Ring. This work presents an application of the the Nested Head-Tail (NHT) formalism for modeling single-bunch transverse instabilities, incorporating analytical solutions to the resistive wall impedances in the absence of space charge. Predicted growth rates and mode structures are benchmarked against PyHEADTAIL simulations and ongoing experimental measurements. The experimental program includes studies of bare-machine instabilities at different machine parameters. These results support the understanding of naturally-occurring instabilities in the Recycler and contribute to the development of predictive tools for beam stability in future high-intensity configurations.

Gonzalez-Ortiz, Cristhian [Fermilab]↗

Modelling of the Nuclear Propulsion Rocket

Nuclear power propulsion rockets are used for the long distance missions in space. National Aeronautical and Space Administration (NASA) has developed several nuclear propulsion rockets since 1950. Especially Nuclear Engine for Rocket Vehicle Application (NERVA) program focused on long term missions in NASA. Planned/unplanned transients on nuclear thermal rockets have to be investigated for these rockets to be sure that they can be utilized for long term missions. This work demonstrates the modelling of nuclear propulsion rocket. By using this new model based on RELAP5 system code, corrosion induced blockages on radiation heat transfer has been investigated for the Pewee I rocket. The blockage locations in the coolant system have been defined based on the experimental data which is available in the literature to use in the computational models. To capture the 3 dimensional (3D) heat transfer modes in the reactor core of Pewee I, a detailed 3D system model has been developed to identify specifically the effect of corrosion on the radiation heat transfer. It was concluded that the pressure drop across the peripheral fuel element coolant holes was also larger than other channels. In addition, it was noticed that radiation heat transfer rate for the channels undergoing blockages increases when the radiation heat transfer rate in their neighbor channels decrease. The temperature of the peripheral fuel elements will gradually get closer to the melting point of Uranium Carbide, especially when the coolant channels undergo the most severe blockage.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Bim-to-fea Conversion Program

The purpose of this program is to enable interoperability between BIM-based architectural design software (i.e., Revit, ArchiCAD, AVEVA E3D) to structural analysis software (i.e., SAP2000). The program takes in BIM building model data via the IFC file format, automatically transforms the architectural coordination entities (structural beams, columns, slabs, walls) to structural analysis entities (i.e., finite element space frames and shells), automatically adjusts the connectivity of the structural analysis entities, and finally exports the structural analysis entities as a structural analysis model contained within a new IFC file. For example, a 3D building in Revit can be exported to an IFC file, run through this BIM-to-FEA program, then the exported IFC can be inputted into SAP2000.

Crowder, Nicholas [Idaho National Laboratory (INL)↗

Symplectic machine learning model for fast simulation of space-charge effects

Symplectic simulation of space-charge effects is crucial for the design and operation of high-intensity particle accelerators. Traditional methods for simulating these effects are often computationally expensive, resulting in significant overhead. In this work, we introduce a generative model based on a U-Net architecture within a generative adversarial network framework to efficiently simulate space-charge effects. The model is trained to predict the transverse multiparticle space-charge Hamiltonian, which can be physically computed using a gridless spectral method. The one-step symplectic transverse transfer map for the particles is then obtained by differentiating the predicted Hamiltonian. Benchmarking results demonstrate that this generative model achieves an order of magnitude higher computational efficiency compared to the spectral method, providing a highly efficient alternative for simulating space-charge effects with a large number of particles. By maintaining symplecticity, the model effectively preserves the phase-space structure and mitigates nonphysical errors in long-term simulations. This model has been integrated into jutrack, a novel autodifferentiable accelerator modeling code developed in the julia programming language.

Beam code development & simulation techniques↗

DEFT: a program for operators in EFT

We describe a Python-based computer program, DEFT, for manipulating operators in effective field theories (EFTs). In its current incarnation, DEFT can be applied to 4-dimensional, Poincaré invariant theories with gauge group SU(3)×SU(2)×U(1), such as the Standard Model (SM), but a variety of extensions (e.g. to lower dimensions or to an arbitrary product of unitary gauge groups) are conceptually straightforward. Amongst other features, the program is able to: (i) check whether an input list of Lagrangian operators (of a given dimension in the EFT expansion) is a basis for the space of operators contributing to S-matrix elements, once redundancies (such as Fierz-Pauli identities, integration by parts, and equations of motion) are taken into account; (ii) generate such a basis (where possible) from an input algorithm; (iii) carry out a change of basis. We describe applications to the SM (where we carry out a number of non-trivial cross-checks) and extensions thereof, and outline how the program may be of use in precision tests of the SM and in the ongoing search for new physics at the LHC and elsewhere. The code and instructions can be downloaded from http://web.physics.ucsb.edu/~dwsuth/DEFT/.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Rapid-Cycling Synchrotron for Multi-Megawatt Proton Facility at Fermilab

The Fermilab accelerator complex delivers intense high-energy proton beams to a variety of fixed-target scientific programs, including a flagship long-baseline neutrino program. With the advent of the Deep Underground Neutrino Experiment (DUNE) and Long Baseline Neutrino Facility (LBNF) program there is strong motivation for a 2.4 MW beam power upgrade of the Fermilab proton facility. We show the Fermilab proton facility can achieve 2.4~MW with a new rapid-cycling synchrotron (RCS) to replace the Fermilab Booster and we provide a comprehensive technical analysis of the RCS-based facility design. Past design efforts and operational experience at the Fermilab Booster, J-PARC RCS, and Oak Ridge SNS are leveraged to provide strong empirical precedent for the design. We provide a parametric study of slip-stacking accumulation, RCS extraction energy, space-charge limits, beampipe aperture, eddy current heating, injection foil heating, and lattice optics. The 2.4 MW benchm ark for the long baseline neutrino program is achieved independently of a previously proposed multi-GeV linac program, but we assess the impact the linac upgrade would have on RCS performance.

43 PARTICLE ACCELERATORS↗

FIRST IMAGES OF DEBRIS DISKS AROUND TWA 7, TWA 25, HD 35650, AND HD 377

We present the first images of four debris disks observed in scattered light around the young (4–250 Myr old) M dwarfs TWA 7 and TWA 25, the K6 star HD 35650, and the G2 star HD 377. We obtained these images by reprocessing archival Hubble Space Telescope NICMOS coronagraph data with modern post-processing techniques as part of the Archival Legacy Investigation of Circumstellar Environments program. All four disks appear faint and compact compared with other debris disks resolved in scattered light. The disks around TWA 25, HD 35650, and HD 377 appear very inclined, while TWA 7's disk is viewed nearly face-on. The surface brightness of HD 35650's disk is strongly asymmetric. These new detections raise the number of disks resolved in scattered light around M and late-K stars from one (the AU Mic system) to four. This new sample of resolved disks enables comparative studies of heretofore scarce debris disks around low-mass stars relative to solar-type stars.

79 ASTRONOMY AND ASTROPHYSICS↗

Scandium functionalized carbon aerogel: Synthesis of nanoparticles and structure of a new ScOCl and properties of NaAlH{sub 4} as a function of pore size

A new method for scandium-functionalization of carbon aerogels forming nanoparticles of a new scandiumoxochloride, ScOCl is presented. Sodium aluminiumhydride, NaAlH{sub 4}, is successfully melt infiltrated into the nano porous scaffolds with pore sizes of D{sub max}=7, 10, 13, 21, 26 and 39 nm, containing scandium based nano particles (<2.9 wt%) confirmed by elemental analysis and scanning electron microscopy. A systematic study of hydrogen storage properties of the nano composite materials is presented. An aqueous solution of ScCl{sub 3} was initially infiltrated and formed nanoconfined [Sc(OH)(H{sub 2}O){sub 5}]{sub 2}Cl{sub 4}(H{sub 2}O){sub 2}, which transforms to nanoparticles of a new scandium oxochloride, ScOCl at 192 °C and to Sc{sub 2}O{sub 3} at 420 °C. ScOCl crystallizes in an orthorhombic unit cell a=3.4409(8), b=3.9613(6) and c=8.178(2) Å, space group Pmmn, and is built from layers of [ScO{sub 4}Cl{sub 2}] octahedra forming neutral ScOCl layers. Temperature programmed desorption mass spectroscopy shows slightly improved kinetics for release of hydrogen with decreasing pore size. Continuous cycling of hydrogen release and uptake measured by the Sieverts' method reveal a larger preserved hydrogen storage capacity for scandium-functionalized aerogel with the larger pores (39 nm). - Highlights: • New synthesis approach for nanoporous Sc-functionalization carbon aerogel (Sc-CA). • The new scandium oxochloride, ScOCl, structure is obtained. • NaAlH{sub 4} nanoconfined in Sc-CA with pores ranging between 7 nm<D{sub max}<39 nm. • Improved H{sub 2} release kinetics obtained with decreasing pore size. • Nanoconfinement (D{sub max}=39 nm) retains 71% of the H{sub 2} capacity after four cycles.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Activation Domain Hunter (ADhunter) v2.0

ADhunter is a software program that enables accurate identification and quantification of transcriptional activation domains. Unlike previous software, ADhunter uses protein representations from a pre-trained protein language model, model ensembling, and a training dataset from a diverse sampling of protein sequence space for state-of-the-art performance. These advantages enable improved perception of transcriptional activation domains across sequence space that can be used for mapping natural genetic circuits and engineering synthetic genetic circuits. In particular, ADhunter enables fine-tuned control of gene expression through synthetic transcription factors that can be used for complex control of cellular programs.

Waldburger, Lucas [Lawrence Berkeley National Labo↗

SU-F-T-190: Homogeneity Study of Proton and Heavy Ion Scanning Beams Based On Different Compositions of Spot Sizes (FWHM) and Grid Sizes

Purpose: Different particle scanning beam delivery systems have different delivery accuracies. This study was performed to determine, for our particle treatment system, an appropriate composition (n=FWHM/GS) of spot size(FWHM) and grid size (GS), which can provide homogenous delivered dose distributions for both proton and heavy ion scanning beam radiotherapy. Methods: We analyzed the delivery errors of our beam delivery system using log files from the treatment of 28 patients. We used a homemade program to simulate square fields for different n values with and without considering the delivery errors and analyzed the homogeneity. All spots were located on a rectilinear grid with equal spacing in the × and y directions. After that, we selected 7 energy levels for both proton and carbon ions. For each energy level, we made 6 square field plans with different n values (1, 1.5, 2, 2.5, 3, 3.5). Then we delivered those plans and used films to measure the homogeneity of each field. Results: For program simulation without delivery errors, when n≥1.1 the homogeneity can be within ±3%. For both proton and carbon program simulations with delivery errors and film measurements, the homogeneity can be within ±3% when n≥2.5. Conclusion: For our facility with system errors, the n≥2.5 is appropriate for maintaining homogeneity within ±3%.

60 APPLIED LIFE SCIENCES↗

Real‐Time Observation of Slowed Charge Density Wave Dynamics in Thinned 1T‐TaS 2

Abstract Transient electrical pulsing is used to investigate the slowed charge density wave (CDW) kinetics of 1T‐TaS 2 . These measurements distinguish a fast response of the material, consistent with the onset of self‐heating, from much slower transients that occur on timescales orders of magnitude longer than this. The latter variations appear consistent with slow configurational changes in the CDW, which, due to the thin nature of the 1T‐TaS 2 , can be distinguished from the much faster dynamics of Joule heating. Experiments in which the cooling of the material is interrupted, demonstrate the possibility of “programming” it in different, strongly nonequilibrium, CDW phases. Collectively, the results point to the existence of a complex free‐energy space for the thinned material, whose multi‐valley structure and hidden metastable states govern the resulting thermal and field‐driven dynamics. Crucially, this work demonstrates that while the CDW dynamics in this material may have a thermal character, the timescales associated with these motions can be very different from those on which self‐heating occurs. This discovery will be important for efforts to implement active devices that utilize the CDW states of thinned 1T‐TaS 2 .

Yin, Shenchu↗

A comparative study of the status of GSHP applications in the United States and China

Ground source heat pump (GSHP) or geothermal heat pump technology was first developed and commercially introduced in the late 1970s, and GSHP units representing approximately 3.9 million tons of cooling had been installed in the United States by 2012. Applications of GSHP technology also have grown rapidly in China since it was introduced into China in the 1990s through collaboration between the Chinese and US governments. It is estimated that by 2013, about 400 million m2 (4.3 billion ft2) of building floor space in China was heated and/or cooled by GSHP systems. Moreover, governments in both China and the United States have programs that in some way support and/or promote the use of GSHP technology. After decades of practice, both countries have accumulated abundant experience in applying GSHP technology, but both also are confronted with various challenges to rapidly deploying this technology. Under the sponsorship of the US–China Clean Energy Research Center for Building Energy Efficiency, researchers reviewed and compared the current status of GSHP applications in the United States and China, including related policies, standards, technologies, equipment, costs, market development, and barriers. Finally, based on this comparative study, future collaborations between the two countries are recommended to improve the application of the GSHP technology and fully realize its energy saving potential.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

TWO SNe Ia AT REDSHIFT ∼2: IMPROVED CLASSIFICATION AND REDSHIFT DETERMINATION WITH MEDIUM-BAND INFRARED IMAGING

We present two supernovae (SNe) discovered with the Hubble Space Telescope (HST) in the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, an HST multi-cycle treasury program. We classify both objects as SNe Ia and find redshifts of z = 1.80 ± 0.02 and 2.26{sup +0.02}{sub −0.10}, the latter of which is the highest redshift SN Ia yet seen. Using light curve fitting we determine luminosity distances and find that both objects are consistent with a standard ΛCDM cosmological model. These SNe were observed using the HST Wide Field Camera 3 infrared detector, with imaging in both wide- and medium-band filters. We demonstrate that the classification and redshift estimates are significantly improved by the inclusion of single-epoch medium-band observations. This medium-band imaging approximates a very low resolution spectrum (λ/Δλ ≲ 100) which can isolate broad spectral absorption features that differentiate SNe Ia from their most common core collapse cousins. This medium-band method is also insensitive to dust extinction and (unlike grism spectroscopy) it is not affected by contamination from the SN host galaxy or other nearby sources. As such, it can provide a more efficient—though less precise—alternative to IR spectroscopy for high-z SNe.

79 ASTRONOMY AND ASTROPHYSICS↗

Commissioning and Operation of FAST Electron Linac at Fermilab

We report results of the beam commissioning and first operation of the 1.3 GHz superconducting RF electron linear accelerator at Fermilab Accelerator Science and Technology (FAST) facility. Construction of the linac was completed and the machine was commissioned with beam in 2017. The maximum total beam energy of about 300 MeV was achieved with the record energy gain of 250 MeV in the ILC-type SRF cryomodule. The pho-toinjector was tuned to produce trains of 200 pC bunches with a frequency of 3 MHz at a repetition rate of 1 Hz. This report describes the aspects of machine commission-ing such as tuning of the SRF cryomodule and beam optics optimization. We also present highlights of an experimental program carried out parasitically during the two-month run, including studies of wake-fields, and advanced beam phase space manipulation.

43 PARTICLE ACCELERATORS↗

Improving the probability tables of the cross section of near closed-shell nuclei [Slides]

The level density distribution of near closed-shell nuclei is much lower than the typical nucleus, therefore, the cross sections show significant fluctuations, and these fluctuations are not predictable. The current methodology used to describe such behavior and construct the probability table of the cross section is based on the extrapolation of the average resonance widths and average resonance spacings from the resonance region and use these parameters to construct the probability table. Although this is a standard and widely used technique, it does not take into account the existing experimental data, such for total and the elastic cross section. Our goal is to extend the current theory and provide a more general approach to compute the probability distribution function of the cross section combining the existing probability tables and the available experimental data. Results will be presented for 90 Zr.

07 ISOTOPE AND RADIATION SOURCES↗