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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 OSTI2017

Fuel Cycle Technologies 2016 Achievements Report

The U.S. Department of Energy (DOE), Office of Nuclear Energy (DOE- NE) established the Fuel Cycle Technologies (FCT) program to address challenges such as growing stockpiles of used nuclear fuel (UNF) and high-level waste (HLW), and an urgency to enhance accident tolerance of the existing reactor fleet. Resolution of these challenges involves developing systems that reduce waste while improving resource utilization and safety. Towards this goal, the FCT program implemented a research and development (R&D) science-based approach, integratesing theory and experiment with high performance computing modeling and simulation. The FCT program establishes and strengthens collaborations with experts at international agencies, universities, and industry to develop the nuclear fuel cycle of the future. DOE-NE national laboratories and their international counterparts provide extensive expertise and experience and access to critical R&D facilities. Universities provide a wellspring of innovative ideas while industry provides the venue to integrate the expertise, experience, and ideas into commercial practice.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2018

MST e-News December 2018

As an enterprising materials scientist, Saryu Fensin leverages both experiments and simulations to improve understanding of how materials behave when subjected to extreme forces. Her aim is to use the complementary techniques to design and develop innovative materials for use in extreme conditions such as stockpile-focused applications.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Phase changes in fluoropolymer binders

Motivation: Understanding fluoropolymer binder structure and aging response continues to be an important goal for the prediction and assessment of polymer bonded explosive compositions within the stockpile. As part of ongoing efforts within NNM, we are developing new methods to quantify crystallization and chemical degradation within aged Fluoropolymer materials. Significance: Time, temperature and radiation are known to alter the mechanical properties of fluoropolymers as crystalline domains nucleate and grow within the material. However, current methods do not accurately quantify and assess the degree or rapidity of these physical aging processes. For this reason, we are developing methods that directly measure crystalline domain, composition, size and shape and cross-correlating them with traditional techniques. Progress: Most recently, we thermally aged fluoropolymer binder, FK800, for various durations up to 23 days at several temperatures including: 25C (red), 35C (green), and 60C (blue). We used wide angle X-ray scattering (WAXS) to observe when crystalline peaks emerged, signaling a phase transition from amorphous to partially crystalline. Some of these data are summarized in Figure 1. As expected, samples held at 25C (red), which is below the glass transition temperature at 28C, remain amorphous – the WAXS data (Figure 1b) lacks sharp peaks indicative of crystallinity and the ultra-small angle X-ray scattering (USAXS) also has a smooth background without peaks indicative of structure (Figure 1a). By contrast, samples held at 35C and 60C have new peaks in both the USAXS and WAXS data. The structure is clearer after subtracting off the amorphous background from the WAXS data (Figure 1c). These data show that samples aged at 60C are more crystalline as determined by the more defined peaks and also have a larger lattice constant as seen by the shift in peak position as compared to the 35C samples. The corresponding USAXS data (Figure 1a) indicate that the size of the crystals was larger at 60C than at 35C as seen by the shift in the knee position to lower q-values. Interestingly, the shape of the scatter curve also changed, which indicates a change in morphology. Atomic force microscopy (AFM) was used to image the fluoropolymer (Figure 1c-e). At 35C, ~50nm long stacked crystal plates are observed. High resolution imaging shows that the stacks consist of 2-6 lamellae that are spaced approximately 3nm apart. At 60C, the individual lamella appear both thicker and longer and are intertwined to fill the surface. Morphological data such as these images help to interpret & model volume averaging techniques like X-ray scattering and NMR. We also expect the shift from isolated islands to intertwined clusters to impact mechanical properties.

36 MATERIALS SCIENCE↗
DOE OSTI2019

ASC news highlight for HQ, 12/11/18

LLNL’s package management tool, Spack, has reduced software build times from weeks to hours for programmatic codes, and the tool’s popularity has grown beyond the NNSA laboratories. New workflow features and ongoing community-building efforts have led ECP and many top supercomputing sites worldwide to adopt Spack as their official deployment tool. With a community of over 330 Spack contributors, the maintenance burden for over 3,000 open source packages is now shared with other centers. This reduction of general ASC software maintenance costs frees up code development resources to address unique requirements specific to the stockpile stewardship mission.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2018

Am-241 Nuclear Safety and Environmental Interactions

NASA’s supply of radioisotopes for Radioisotope Heat Units (RHU) and Radioisotope Thermoelectric Generator (RTG) power sources is facing a crisis due to shortages of Pu-238 for future missions. Am-241 is a possible replacement for Pu-238 since its stockpile from the nuclear weapons program has remained relatively intact. The purpose of this project was to assess the safety of Am-241 and the risks associated with it as compared with PU-238. The project has resulted in a journal article, F. De-La-Torre-Aguilar, N. White, M. Prelas, R. V. Tompson, and S. K. Loyalka "Space nuclear power system accidents: Doses from Pu-238 and Am- 241 inhalation," Progress in Nuclear Energy vol.100C (2017), pp.171-182, which showed that the radiation dosage resulting from Am-241 inhalation are about 1/2.5 of the dosage resulting from Pu-238 inhalation per KW of Pu-238 power. Considerable progress was also made on the Direct Simulation Monte Carlo Method (DSMC) for simulation of aerosol evolution during accidents resulting in three publications: 1.I. Saldivar, F. De-La-Torre-Aguilar, M. Boraas, and S. K. Loyalka “Benchmark problems in aerosol evolution: Comparison of some exact and DSMC results” in Annals of Nuclear Energy vol.117 (2018), pp.213-222. 2. I. Saldivar and S. K. Loyalka, “Evolution of Aerosols Coupled to Environments: Verification of Direct Simulation Monte Carlo (DSMC)”, Nuclear Technology 204 (2018), pp.172-183. 3. M. Boraas and S. K. Loyalka, “Mesh Free Simulation of Spatially Inhomogeneous aerosols in Arbitrary Geometries” Nuclear Science and Engineering (2018). Further, we have computations on Am-241/Pu-238 vapor and aerosol interactions, and found that the vapor condensation rate is relatively insensitive to the mass effects, confirming some previous results. We have also completed computations of charge effects on evolution of different species aerosols and a manuscript is in preparation. Additionally, we have compared atmospheric dispersion and deposition of Pu-238 and Am-241 using the HYSPLIT code. We have also used a real lung model and the CFD program FLUENT to compute PuO2 and AmO2 deposition to explore improvements upon the ICPR-66 model. We have found that the deposition efficiencies of PuO2 and AmO2 are similar. These results (four manuscripts) will be submitted for publication in the post project period. We have made progress using framework of Mars 2020 mission nuclear risk assessment model to integrate all results, but our progress has been limited as the improved consequence modeling itself has been quite involved and challenging. We will integrate and complete the more extensive risk modeling computations and publish the results in the post-project period. In addition to the above, the project has resulted in research training of four PhD students

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2018

Sierra Structural Dynamics Code Verification Plan

Verification and validation (V&V) of scientific computing programs are important at San- dia National Laboratories (SNL) due to the expanding role of computational simulation in managing the United States nuclear stockpile. This document presents the verification plan for the Sierra Structural Dynamics application. This verification plan includes code devel- opment practices, structure of test suites, and additional quality assurance practices used by the Sierra/SD team.

42 ENGINEERING↗
DOE OSTI2015

2014 Annual Site Environmental Report Summary Pamphlet for Sandia National Laboratories New Mexico

Sandia Corporation's (Sandia's) enduring core mission is to provide science and engineering support for the nation's nuclear weapons stockpile. Today, the mission encompasses additional critical aspects of national security, including developing technologies and strategies for responding to emerging threats, protecting and preventing the disruption of critical infrastructures, and supporting the nonproliferation of weapons of mass destruction. Sandia also collaborates with representatives from other government agencies, the industrial sector, and universities to develop and commercialize new technologies.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

How Los Alamos helped extend the life of the W76 warhead for the U.S. Navy

The Department of Energy’s National Nuclear Security Administration (NNSA) celebrated the completion of the Program of Record for the W76-1 Mk 4A Life Extension Program (LEP) on Jan. 24 at the Pantex Plant in Amarillo, Texas. The W76-1 is a modernized W76-0 warhead, which is a submarine-launched ballistic missile system first introduced into the stockpile for the U.S. Navy in 1978. This LEP has strengthened the safety and security of the United States and its allies by extending the warhead’s service life for another 20 years.

James Owen↗
DOE OSTI2019

Opacity: A window into High Energy Density Plasma Physics

Opacity is a fundamental property of matter and knowledge of it is required to understand the transport of radiation through a material. Exact knowledge of opacity is crucial in many fields such as astrophysics, which recently produced a white paper on the current state of astrophysical opacities [1], plasma physics, including inertial confinement fusion (ICF) and magnetic confinement fusion, high energy density physics (HEDP), the semiconductor industry [2] and stockpile stewardship. In industry, the accurate knowledge of the opacity of tin is important for extreme ultraviolet (EUV) lithography and the development of processors with smaller components. In astrophysics, Cepheid variable stars are used as “standard candles” for determining the distance to objects. Opacities of these stars are required to understand the relationship between their periodicity, luminosity and distance. Our sun is the most studied star and provides the basis of our understanding for other stars. Yet in significant ways the sun is poorly understood. In recent years, there has been a debate over the abundances of heavy elements (Z > 2) in the solar interior. Current solar atmosphere models [3] find a significantly lower abundance for C, N, and O compared to models used roughly a decade ago. Although solar evolution models have matured, a discrepancy still exists between spectroscopic solar models (which require opacities) with updated abundances, and solar properties inferred from helioseismology and neutrinos [4]. Despite its necessity, opacity is not solved, and is an open and active area of research needed for improving our understanding of plasma physics.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2017

Durability of Corrosion Protection Coatings for Aluminum

The objectives of this work are to (1) Develop a detailed understanding of the performance characteristics of current chromate conversion coatings utilized in the stockpile, (2) Develop a detailed understanding of the performance characteristics of non-chromate conversion coatings proposed to replace their chromate containing counterparts, (3) Provide an informed assessment of the aforementioned coatings and a recommended course of action for the replacement of chromate containing coatings, and (4) establish subject matter expertise in the area of replacement coatings to provide as a resource to the systems organization. These tasks will be accomplished by performing a battery of traditional corrosion performance tests (in accordance with the relevant MIL specifications governing chemical conversion coatings), combined with more detailed analytical evaluation of the materials. Coatings will be evaluated in the as-received and artificially aged condition. Four different coating systems were evaluated on four different aluminum alloys in FY16. The focus this year was to continue populating the test matrix initiated in previous years, evaluating key coatings in the as received and thermally stressed condition, as compared to the baseline chromate conversion coating (Bonderite (formerly Alodine) 1200S). The non-chromate conversion coatings included Bonderite T 5900, Chemeon TCP-HF, Luster-On Aluminescent, and MacDermid-Enthone Iridite NCP. A second effort that was completed this year was to address a bottleneck that existed for the electrical evaluation of the coatings, assessing their conformance with the MIL specification. An electromechanical test system was assembled and automated, eliminating the need to rely on an already heavily utilized mechanical test system and operator in Materials Mechanics and Tribology.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Conversion of Coal Wastes and Coal Plus Other Opportunity Fuel Mixtures, Such as Coal Plus Municipal Solids, to Produce Electricity and/or Liquid Fuels

For the foreseeable future, the Nation’s energy demand will continue to come largely from indigenous fossil energy resources and hydrocarbon fuels. Specifically waste coal plus other opportunity fuels need to be utilized as a feedstock to eliminate a waste stream and optimized to maximize energy yield and cleanly minimize pollutant emissions. Modular equipment is needed for installation in coal preparation locations, military installations, and research park facilities. Thermal decomposition of coal, biomass, and mixed solid waste (MSW) have been shown to reduce a waste stream while providing liquid and gaseous fuel products with low pollutant emissions. However, thermal decomposition processes have several challenges associated with preprocessing biomass and MSW, feeding and conveying material into the reactor, and post processing of syngas to remove undesirable products while upgrading to increase yield of high value products. Increasing total energy output from power plants by utilizing biomass and mixed wastes ultimately lowers energy costs, harmful environmental impacts of emissions, and has significant impacts on the energy security and sustainability of the U.S. economy. Entrained flow gasifiers (EFGs) produce very little CH4 and a wide range of H2/CO ratios (0.5–2.0) but are limited in their ability to effectively feed large biomass or MSW particles into the reactor. A solution to the feeding problems is to use pyrolysis torrefaction (PT) for conversion of waste materials to create a feedstock similar to coal and capable of grinding down and mixing with the coal feed. Mainstream experimentally explored reaction pathways for the conversion of coal waste plus municipal solids (CWPMS) and demonstrated a bench-scale reactor used for torrefaction of the municipal solid waste (MSW) to create a coal-like feed for blending with the coal waste. The material was processed in a pilot-scale EFG to determine product yield and emissions with CWPMS fuels, as well as the ash content and slagging properties of these feedstocks. The PT-EFG system was experimentally validated, where emissions and yield data were used to develop a high-fidelity process model and economic analysis. The following was accomplished in the Phase I: Determined optimal torrefaction process conditions for MSW and biomass through TGA; maximized heating value of fuel while maximizing final mass of torrefied product Demonstrated torrefaction of MSW and biomass feedstocks at 334°C, pulverized to uniform 74 µm particle size, and processed into coal-like feedstocks Demonstrated 8 lb/h pilot-scale EFG using MSW and biomass blends with waste coal; demonstrated 100% biomass in EFG Determined major effects of MSW torrefaction and co-gasifying high-ash coal waste-MSW blends have on pilot-scale EFG Demonstrated blending low-ash, low-sulfur torrefied biomass with high-ash waste bituminous and anthracite refuse coals generates a higher quality syngas compared to syngas from high-ash waste coals Demonstrated a high carbon conversion (> 99.5%) and syngas with 29.47% H2 content, and 0% CH4 content; greater water–gas shift occurs in EFG than predicted by equilibrium ASPEN Plus model Blended lower-ash, high-alkali biomass MSW to lower slag viscosities of the high-ash coal refuse sufficiently for better slag flow compared to feeding the high-ash coal Used low-sulfur biomass to greatly reduce the EFG syngas H2S concentrations and produce non-leachable slag and quench water with very little organic and trace metal contamination Developed a process model and TEA showing the modular PT EFG is cost competitive to existing power plants with the advantage of using low- or negative-value feedstocks such as waste coal stockpiles and non-landfilled MSW; providing a large incentive to implement an economical PT-EFG process

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2017

U.S. Coal Industry Perspective

This report provides an overview of the coal industry, focusing on the United States. Some of the areas covered include coal prices, consumption, production, stockpiles, imports, exports, reserves, and productivity measures. Juxtapositions between the United States and other countries' coal industries are provided. In addition to providing a current snapshot of the U.S. coal industry, this work portrays both historical and projected aspects of the coal industry.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2019

Continuous Flow Biocatalytic Generation of Green Propellant Fuels

Rocket propulsion has largely relied on the monopropellant hydrazine for the past four decades. However, hydrazine is both highly toxic and highly flammable, requiring expensive cold storage, specialized handling, and complex disposal protocols. Alternative propellant fuels for powering satellites and spacecraft offer greener and safer solutions that are more efficient (energetically dense) and less expensive, and on-demand manufacturing approaches eliminate stockpiling and storage needs for ensuring user-ready access to rocket fuels.

09 BIOMASS FUELS↗
DOE OSTI2018

User Requirements Specification for the Universal Real Time Controller: Ergonomic Design for Placement of Three NI 9157/9159 Chassis

The Air Delivered Weapons Tester Development Group (2256) is currently designing a new type of test system, the Universal Real Time Controller (URTCON). The URTCON will provide the surveillance community with technologies that advance the state of knowledge in stockpile stewardship. Success for its implementation depends on whether the components comprising the URTCON can be reliably and accurately maintained in the field. A system is maintainable when the worker has visual and physical access to the components that need to be serviced. To address this need, a layout was determined that best facilitates the worker's ability to easily see and reach components. A list of user-system requirements was initially prepared to guide decisions affecting the layout. Then, five design options depicting various ways to lay out the components were evaluated. Based on this effort, a best design option was identified for implementation. It is expected that the design recommended herein will provide the workers with a workplace that permits unhindered access to the components requiring their attention.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2018

US Naval Academy: Internship After-Action Report (AAR)

DTRA and NNSA need to understand certain energetic products in order to define requirements for ongoing nuclear weapon enterprise programs. By characterizing shaped charges, for example, we can proactively protect our existing nuclear stockpile. Being able to effectively and accurately model these characteristics allows us to more efficiently utilize time, money, and resources so that we can best protect our assets. I was partnered with another midshipman to work on this project with our advisor, along with a team of explosives technicians, and several specialists in computational simulations. In order to determine the pressure field created by the jet and the jet velocity, I worked with and modified simulations using CTH, a code developed at Sandia. I compared values from the simulation to what was determined experimentally.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2015

Nevada National Security Site Environmental Report 2014--Summary

This Nevada National Security Site Environmental Report (NNSSER) was prepared to satisfy DOE Order DOE O 231.1B, “Environment, Safety and Health reporting.” Its purpose is to (1) report compliance status with environmental standards and requirements, (2) present results of environmental monitoring of radiological and nonradiological effluents, (3) report estimated radiological doses to the public from releases of radioactive material, (4) summarize environmental incidents of noncompliance and actions taken in response to them, (5) describe the National Nuclear Security Administration Nevada Field Office Environmental (NSA/NFO) Management System and characterize its performance, and (6) highlight significant environmental programs and efforts. The three major NNSS missions include National Security/Defense, Environmental Management, and Nondefense. The major programs that support these missions are Stockpile Stewardship and Management, Nonproliferation and Counterterrorism, Nuclear Emergency Response, Strategic Partnership Project, Environmental Restoration, Waste Management, Conservation and Renewable Energy, Other Research and Development, and Infrastructure. The major facilities that support the programs include the U1a Facility, Big Explosives Experimental Facility (BEEF), Device Assembly Facility, Dense Plasma Focus Facility, Joint Actinide Shock Physics Experimental Research Facility, Radiological/Nuclear Countermeasures Test and Evaluation Complex, Nonproliferation Test and Evaluation Complex (NPTEC), Radiological/Nuclear Weapons of Mass Destruction Incident Exercise Site, Area 5 Radioactive Waste Management Complex (RWMC), and the Area 3 Radioactive Waste Management Site (RWMS).

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Magnetic resonance imaging techniques are being developed to measure the in-situ reactions of polysiloxanes

Polysiloxane foams utilized for stockpile applications experience changes over time induced by exposure to thermal, radiative, and mechanical stresses. The interplay of these stresses can lead to chemical and/or physical changes in the polymer, such as alterations of compression set. Understanding these mechanisms require us to understand the in-situ stress states that these polymeric foams are exposed to in the service environment.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗