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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 343 records · Page 19
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Estane Molecular Weight Analysis in PBX 9501 Samples; Slice 'N Dice Study

T Division is creating a model of aging in PBX 9501 that will benefit from molecular weight mapping of hemispherical charges (“hemi’s”) that have been in the stockpile. Two hemi’s were prepared at Pantex by machining out sections and then machining those sections into cubes, which is why the project is referred to as a “Slice ‘N Dice” study. Two sections were cut from each hemi. One section was used for density mapping and the other was for molecular weight analysis. The molecular weight section pieces were cut so that both Pantex and LANL would be able to analyze cubes from approximately the same areas in order to compare results. Pantex analyzed all of their samples earlier in 2011. LANL’s Slice ‘N Dice samples were received in February of 2012 where they were inventoried, weighed and prepared by WX-7 and analyzed by both WX-7 and MST-7.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2012

Radiochemistry Results from IER-163 Comet Irradiation

A critical experiment was performed on the Comet assembly to provide nuclear data in a non-thermal neutron spectrum and to re-establish experimental capability relevant to the Stockpile Stewardship and Technical Nuclear Forensic programs. Irradiation foils were placed at specific locations in the Zeus all oralloy critical experiment to obtain fission ratios and activation products. After the irradiation was completed and a cooling down period of time had elapsed, passive gamma ray measurements were performed on all the foils and several of the foils were packaged and shipped to Los Alamos National Laboratory (LANL) for further radiochemical analysis. The results from the Los Alamos National Laboratory’s non-destructive and radiochemical analyses are presented. Monte Carlo simulations of the experiment are described and compared to the experimental results.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2012

Chemical analysis of uranium-niobium alloys by wavelength dispersive spectroscopy at the sigma complex

Uranium-niobium alloys play an important role in the nation's nuclear stockpile. It is possible to chemically quantify this alloy at a micron scale by using a technique know as wavelength dispersive spectroscopy. This report documents how this technique was used and how it is possible to reproduce measurements of this type. Discussion regarding the accuracy and precision of the measurements, the development of standards, and the comparison of different ways to model the matrices are all presented.

36 MATERIALS SCIENCE↗
DOE OSTI2013

AOT & LANSCE Focus: Proton Radiography Facility

Invented at Los Alamos National Laboratory, proton radiography (pRad) at the Los Alamos Neutron Science Center (LANSCE) employs a high-energy proton beam to image the properties and behavior of materials under a variety of conditions. The penetrating power of high-energy protons, like that of x-rays, makes them an excellent probe of a wide range of materials under extreme pressures, strains, and strain rates. The invention of proton radiography is the direct result of the synergy between the Laboratory’s defense mission and basic science research scientists and supports the Laboratory’s national security science mission as well as provides for fundamental science discoveries. This new capability has revolutionized dynamic materials science at Los Alamos, providing a new window for the study of shock physics, materials damage, and high explosives science. The Proton Radiograpy Facility, a national user facility, has performed more than 500 dynamic experiments in support of the Weapons program, Global Security, and other customers since it was commissioned more than a decade ago. This information helps Los Alamos maintain the reliability of the U.S. nuclear stockpile. The pRad capability is primarily supported by the NNSA Science Campaigns.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Applying QMU to Nuclear Weapon Stewardship

Quantification of Margins and Uncertainty (QMU) is a principle means and metric by which nuclear weapons performance is measured. At Lawrence Livermore National Laboratory (LLNL), Nuclear weapon QMU is predominately a Physics assessment of the performance margin and associated uncertainties of not achieving the designed nuclear performance. To more completely apply QMU to Nuclear Weapon Stewardship, a Systems Engineering or systematic approach is being employed to identify and define requirements, allowing assessment of performance with QMU. This paper describes the basics of QMU and how it is applied below the highest level nuclear performance function down and throughout the nuclear weapon design architecture. The intended audience for this paper is a novice QMU practitioner at LLNL. The application of QMU to the entire set of nuclear weapon functions demands a broad engagement of Science and Engineering disciplines. Using a hierarchical flow-down requirements structure, performance functions and failure modes are identified for all levels of system requirements. There can be multiple failure modes per functional requirement. For each function there is a spectrum of possible outputs that can vary from outright failure to excellent performance. The possible consequences and impacts on the next higher level functions will also vary. Since performance variations exist in a weapon functional hierarchy, the assessment process needs and benefits from a system perspective. Incorporating QMU into assessments using a Systems Engineering approach to stockpile management provides a means to quantify weapon performance risks against a multitude of possible failure modes and from the highest level functions down to the lowest level component functionality. Performance risk management is a core practice of nuclear weapon management. Assessing the likelihood and consequences of the many possible failure modes is done yearly as part of Annual Assessment Reviews (AAR). When annual surveillance discovers an anomaly defect as part of weapon surveillance, investigations are launched and QMU is a key tool for quantifying performance impacts. QMU assessments are separated into two pieces, failure mode assessments and QMU analysis.

42 ENGINEERING↗
DOE OSTI2014

LANL B61 System FY 2014 Q1 Report

This report provides a status report for the LANL Stockpile System for quarter 1 of FY 2014.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2011

Strategic planning for power system restoration

This contribution to NISAC's fast response is to answer the problem of how to stockpile power system components throughout a state to minimize the restoration time after a natural disaster.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2011

Gas analysis for LANL weapons surveillance

Gas analysis is performed at LANL as one part of weapons surveillance conducted to identify stockpile aging concerns and to predict the lifetime of weapon components and materials. These analyses include gas dissolved in and evolved from polymeric materials. Radiolysis and thermal decomposition of polymers are examples of processes which lead to gas production. These are accessed using canister aging studies with gas analysis typically performed using gas chromatography and gas chromatography/mass spectrometry. More recently we have developed methods to measure dissolved gases in polymeric materials suspect in the failure of potting materials. This talk provides a brief overview of recent work.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Thermodynamic database development: Al-Am-Ga-Pu-U

The goal of this study is about the thermodynamic re-assessment of the Plutonium- Uranium (Pu-U) system as a first step leading to the development of a plutonium-based thermodynamic database (i.e., Pu with Al, Am, Ga, Mo, U…) with resulting phase diagrams and associated thermodynamic data. Indeed, phase stability trends and phase diagrams of multi-component nuclear materials are crucial for predicting properties and performance under normal, hypothetical or even accidental conditions. This work is based on a coupling between ab initio energetics, phenomenological thermodynamics models - based on the CALPHAD (CALculation of PHAse Diagrams) approach - and the use of the Thermo-Calc software, together with experimental data (whenever available). The present report summarizes results obtained (quarter period: 10/07/2013-01/07/2014) under the auspices of an agreement between CEA/DAM and NNSA/DP on cooperation in fundamental science supporting stockpile stewardship (P182).

36 MATERIALS SCIENCE↗
DOE OSTI2014

The high-foot implosion campaign on the National Ignition Facility

If you could identify only one key skill that a primary or secondary designer should possess, it would be the ability to design an implosion that works reliably and as advertised. Being able to harness an implosion is a key skill because of what an implosion does – an implosion is a “pressure amplifier” that takes absorbed energy and turns that energy, with significant energy loss, into pressure. The pressure generated in implosions is used to compress materials to high densities in the primary designers case, and high densities and temperatures in the secondary designers case. While primary designers and their simulation tools can be tested against experiments at scale fielded at high-explosive facilities around the NNSA complex, secondary designers are much more limited in the experimental facilities that can access relevant conditions (facilities such as Omega at the Laboratory for Laser Energetics, the Z-machine at Sandia National Lab in Albuquerque and the National Ignition Facility at Livermore are more-or-less it). Ignition conditions are the highest-pressure and therefore hardest conditions to access with facility levels of energy, but the struggle to obtain ignition has been an illuminating test of the stockpile stewardship model. If you thought the criteria for ignition is when the fusion energy output from an inertially confined fusion (ICF) implosion exceeds the energy delivered to the target, you’d be wrong. While the above definition is used for milestone tracking purposes, the actually definition of ignition that has been used in fusion research since 1957 is when the power produced by the fusing region exceeds the rate at which energy is lost from the fusing region due to x-ray radiation processes and heat conduction processes. This simple statement about fusion power and rates of energy loss lead to a quantitative criterion for ignition that is known as the “Lawson Criteria.”

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2011

Aging of Weapon Seals – An Update on Butyl O-ring Issues

During testing under the Enhanced Surveillance Campaign in 2001, preliminary data detected a previously unknown and potentially serious concern with recently procured butyl o-rings on several programs. All butyl o-rings molded from a proprietary formulation throughout the period circa 1999 through 2001 had less than a full cure. Engineering judgment was that under curing is detrimental and could possibly lead to sub-optimum performance or, in the worst case, premature seal failure. An aging study was undertaken to ensure that suspect o-rings installed in the stockpile will retain sufficient sealing force for a minimum ten-year service life. A new prediction model developed for this study indicates suspect o-rings do not need to be replaced before the ten-year service life. Long-term testing results are reported on a yearly basis to validate the prediction model. This report documents the aging results for the period September 2002 to January 2011.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2012

Fiscal Year 2012 Institutional Commitments [Slides]

Assess the safety, reliability, and performance of LANL weapons systems. Achieve NNSA's Weapon Complex Transformation for the nation's nuclear weapons stockpile and meet national security requirements. Provide early identification, creative maturation, and timely delivery of scientific solutions to technically challenging security issues. Become the premier capabilities-based national security science Laboratory . Develop sustainable solutions that allow resilient adaptation to growing global energy demand. Make safety and security integral to every activity we do. Reduce risks while providing seamless information services. Establish excellence in environmental stewardship. Provide efficient, compliant, and secure infrastructure supported with disciplined operations. Enable mission and operational excellence. Deliver cost effective business systems that meet LANL's business needs. Demonstrate our value as a national security science Laboratory, as an employer, and as a good corporate citizen by communicating effectively with our employees, customers, community, and stakeholders while successfully executing our community commitments. Cultivate a work environment where employees are empowered to achieve success.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2014

Science and Technology Review (March 2014)

Over the past few years, Lawrence Livermore has experienced a surge of innovation in radiochemistry—the science of generating, identifying, isolating, and characterizing the radioactive isotopes of chemical elements. For example, Livermore researchers have developed a technique for producing double-sided target foils and built a target surface mapping tool, which increased the productivity of stockpile stewardship experiments. Radiochemists are also using the Laboratory’s particle accelerator to measure nuclear reaction products for reactor safety and nuclear forensics research. Another Livermore team is making synthetic nuclear debris samples with ingredients that more closely match debris from a real explosion for use in isotope identification exercises. Researchers are also refining the chemicals and protocols required to perform wet-chemistry experiments on transactinides, shortlived heavy elements such as flerovium and livermorium. A collaboration with two universities is developing a portable, automated system that can quickly capture, prepare, and chemically test radioisotopes.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2014

Site environmental report for 2013. Sandia National Laboratories, California.

Sandia National Laboratories (SNL) is one of three national laboratories supporting the United States Department of Energy (DOE) statutory responsibilities for nuclear weapon research and design, development of energy technologies, and basic scientific research. SNL facilities are located in New Mexico, California, Nevada, and Hawaii. Sandia National Laboratories, California (SNL/CA) is a multi-program engineering and science laboratory supporting the nuclear weapons stockpile program, energy and environment research, homeland security, micro- and nano-technologies, and basic science and engineering research.

Larsen, Barbara L.↗
DOE OSTI2014

Excavationless Exterior Foundation Insulation Field Study

Building science research supports installing exterior (soil side) foundation insulation as the optimal method to enhance the hygrothermal performance of new homes. With exterior foundation insulation, water management strategies are maximized while insulating the basement space and ensuring a more even temperature at the foundation wall. However, such an approach can be very costly and disruptive when applied to an existing home, requiring deep excavation around the entire house. The NorthernSTAR Building America Partnership team implemented an innovative, minimally invasive foundation insulation upgrade technique on an existing home. The approach consisted of using hydrovac excavation technology combined with a liquid insulating foam. The team was able to excavate a continuous 4" wide by 4' to 5' deep trench around the entire house, 128 linear feet, except for one small part under the stoop that was obstructed with concrete debris. The combination pressure washer and vacuum extraction technology also enabled the elimination of large trenches and soil stockpiles normally produced by backhoe excavation. The resulting trench was filled with liquid insulating foam, which also served as a water-control layer of the assembly. The insulation was brought above grade using a liquid foam/rigid foam hybrid system and terminated at the top of the rim joist. Cost savings over the traditional excavation process ranged from 23% to 50%. The excavationless process could result in even greater savings since replacement of building structures, exterior features, utility meters, and landscaping would be minimal or non-existent in an excavationless process.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Where Big Data and Prediction Meet

Our ability to assemble and analyze massive data sets, often referred to under the title of “big data”, is an increasingly important tool for shaping national policy. This in turn has introduced issues from privacy concerns to cyber security. But as IBM’s John Kelly emphasized in the last Innovation, making sense of the vast arrays of data will require radically new computing tools. In the past, technologies and tools for analysis of big data were viewed as quite different from the traditional realm of high performance computing (HPC) with its huge models of phenomena such as global climate or supporting the nuclear test moratorium. Looking ahead, this will change with very positive benefits for both worlds. Societal issues such as global security, economic planning and genetic analysis demand increased understanding that goes beyond existing data analysis and reduction. The modeling world often produces simulations that are complex compositions of mathematical models and experimental data. This has resulted in outstanding successes such as the annual assessment of the state of the US nuclear weapons stockpile without underground nuclear testing. Ironically, while there were historically many test conducted, this body of data provides only modest insight into the underlying physics of the system. A great deal of emphasis was thus placed on the level of confidence we can develop for the predictions. As data analytics and simulation come together, there is a growing need to assess the confidence levels in both data being gathered and the complex models used to make predictions. An example of this is assuring the security or optimizing the performance of critical infrastructure systems such as the power grid. If one wants to understand the vulnerabilities of the system or impacts of predicted threats, full scales tests of the grid against threat scenarios are unlikely. Preventive measures would need to be predicated on well-defined margins of confidence in order to take mitigating actions that could have wide ranging impacts. There is a rich opportunity for interaction and exchange between the HPC simulation and data analytics communities.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2015

CCC7-119 Reactive Molecular Dynamics Simulations of Hot Spot Growth in Shocked Energetic Materials

The purpose of this work is to understand how defects control initiation in energetic materials used in stockpile components; Sequoia gives us the core-count to run very large-scale simulations of up to 10 million atoms and; Using an OpenMP threaded implementation of the ReaxFF package in LAMMPS, we have been able to get good parallel efficiency running on 16k nodes of Sequoia, with 1 hardware thread per core.

74 ATOMIC AND MOLECULAR PHYSICS↗