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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 OSTI2013

Development of a Generalized Methodology for Soil-Structure Interaction Analysis Using Nonlinear Time-Domain TechniquesNEAMS Program, DOE Office of Nuclear Energy (NE-41)

A generalized time-domain method for Soil-Structure Interaction Analysis is developed, based upon an extension of the Bielak Method. The methodology is combined with the use of a simple hysteretic soil model based upon the Ramberg-Osgood formulation and applied to a notional Small Modular Reactor. These benchmark results compare well with those obtained by using the industry-standard frequency-domain code SASSI. The methodology provides a path forward for investigation of other sources of nonlinearity, including those associated with the use of more physically-realistic material models incorporating pore-pressure effects, gap opening/closing, the effect of nonlinear structural elements, and 3D seismic inputs.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2013

Reductions without Regret: Details - Avoiding Box Canyons, Roach Motels, and Wrong Turns

The United States is concurrently pursuing the goals of reducing the size of its nuclear weapons force – strategic and non-strategic, deployed and non-deployed – and of modernizing the weapons it continues to possess. Many of the existing systems were deployed 30 to 50 years ago, and the modernization process can be expected to extend over the next decade or more. Given the impossibility of predicting the future over the lifetime of systems that could extend to the end of this century, it is essential that dead ends in force development be avoided, and the flexibility and availability of options be retained that allow for: • Scalability downward in the event that further reductions are agreed upon; • Reposturing to respond to changes in threat levels and to new nuclear actors; and • Breakout response in the event that a competitor significantly increases its force size or force capability, In this paper, we examine the current motivations for reductions and modernization; review a number of historical systems and the attendant capabilities that have been eliminated in recent decades; discuss the current path forward for the U.S. nuclear force; provide a view of the evolving deterrence situation and our assessment of the uncertainties involved; and present examples of possibly problematic directions in force development. We close with our thoughts on how to maintain flexibility and the availability of options for which a need might recur in the future.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2013

Data Management Technology Survey and Recommendation

The Data Management Plan (DMP) document already released describes the architecture and plan for developing the data management framework needed by the Carbon Capture Simulation Initiative (CCSI) toolset. The CCSI toolset includes: experimental data, physical property methods and parameters, empirical correlations, validation data set, models, simulation inputs and outputs, reduced-order models, cost models, risk models, uncertainty estimation, etc. Each tool in the toolset requires and generates data, and the data management system organizes and stores the data. The data management framework will be driven by end-users and interact with CCSI workflow components such as Turbine. This document reports on the technology survey completed as the first step in the Data Management Plan. It also provides recommendations for a path forward based on the survey results.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2013

Development of spray coated cathodes for RITS-6.

This report documents work conducted in FY13 to conduct a feasibility study on thermal spray coated cathodes to be used in the RITS-6 accelerator in an attempt to improve surface uniformity and repeatability. Currently, the cathodes are coated with colloidal silver by means of painting by hand. It is believed that improving the cathode coating process could simplify experimental setup and improve flash x-ray radiographic performance. This report documents the experimental setup and summarizes the results of our feasibility study. Lastly, it describes the path forward and potential challenges that must be overcome in order to improve the process for creating uniform and repeatable silver coatings for cathodes.

Simpson, Sean↗
DOE OSTI2013

High-voltage atmospheric breakdown across intervening rutile dielectrics.

This report documents work conducted in FY13 on electrical discharge experiments performed to develop predictive computational models of the fundamental processes of surface breakdown in the vicinity of high-permittivity material interfaces. Further, experiments were conducted to determine if free carrier electrons could be excited into the conduction band thus lowering the effective breakdown voltage when UV photons (4.66 eV) from a high energy pulsed laser were incident on the rutile sample. This report documents the numerical approach, the experimental setup, and summarizes the data and simulations. Lastly, it describes the path forward and challenges that must be overcome in order to improve future experiments for characterizing the breakdown behavior for rutile.

Williamson, Kenneth Martin↗
DOE OSTI2013

LLNL HEPA Filter Support of Nuclear Facility Safety R&D (FY12)

The ceramic HEPA filter project has been a successful and innovative project. This report contains information from the work from FY12 funding, as well as remaining FY11 funding. Of note, a total of 12 patents for the ceramic HEPA filter program have been filed, and an additional record of invention has been prepared with a provisional patent to follow. This project supports development of a ceramic HEPA filter technology to benefit DOE nuclear facilities by providing lower life-cycle costs and reducing or eliminating costs associated with Safety Class and Safety Significant systems in nuclear facilities. The satisfactory performance of ceramic filters in a fire could significantly reduce costs of support systems associated with mitigating a release, such as fire suppression, fire detection and alarm, and internal building structure. In nuclear safety, the best way to provide protection to public, workers and the environment is to provide a barrier between the hazard and the receptors. A passive engineered design feature is the best barrier for that purpose. Advanced ceramic HEPA filters provide an excellent barrier between radioactive material in a nuclear facility and everything downwind. Both university (Cal Poly) student teams did very well. As summarized in this report, they successfully added and upgraded instrumentation and controls to the High Temperature Test Unit (HTTU) for the ceramic filter project. They also succeeded in adding viewing ports, remotely controlled closed circuit television, a flame impingement system and a helium filter gasket leak detection system. Details can be found in Ref. 3 - 6. The HTTU has flexible capabilities and can also be used to test other types of filters or filter components in the future, if so desired. At LLNL, research to improve filter media coating (Fig. 1) is being conducted to maintain filtration efficiency while improving performance (reducing pressure drop). Improvements in the individual filter element are necessary to maintain filtration efficiency while decreasing pressure drop. The path forward for an optimal ceramic HEPA filter meeting DOE’s needs is to improve the filtration media. This task utilized the LLNL/DOE developed innovations along with progress in previous activities to prepare multiple ceramic filter elements and refine the technical details for depositing advanced filtration materials to the ceramic filter to meet desired filter performance. The ceramics filter elements were tested for pressure drop at the required air flow rate using an air flow test system. The filtration efficiency and pressure drop of the ceramic filter elements will be measured as part of the development process.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2013

A feasibility and optimization study to determine cooling time and burnup of advanced test reactor fuels using a nondestructive technique

The goal of this study presented is to determine the best available non-destructive technique necessary to collect validation data as well as to determine burn-up and cooling time of the fuel elements onsite at the Advanced Test Reactor (ATR) canal. This study makes a recommendation of the viability of implementing a permanent fuel scanning system at the ATR canal and leads3 to the full design of a permanent fuel scan system. The study consisted at first in determining if it was possible and which equipment was necessary to collect useful spectra from ATR fuel elements at the canal adjacent to the reactor. Once it was establish that useful spectra can be obtained at the ATR canal the next step was to determine which detector and which configuration was better suited to predict burnup and cooling time of fuel elements non-destructively. Three different detectors of High Purity Germanium (HPGe), Lanthanum Bromide (LaBr3), and High Pressure Xenon (HPXe) in two system configurations of above and below the water pool were used during the study. The data collected and analyzed was used to create burnup and cooling time calibration prediction curves for ATR fuel. The next stage of the study was to determine which of the three detectors tested was better suited for the permanent system. From spectra taken and the calibration curves obtained, it was determined that although the HPGe detector yielded better results, a detector that could better withstand the harsh environment of the ATR canal was needed. The in-situ nature of the measurements required a rugged fuel scanning system, low in maintenance and easy to control system. Based on the ATR canal feasibility measurements and calibration results it was determined that the LaBr3 detector was the best alternative for canal in-situ measurements; however in order to enhance the quality of the spectra collected using this scintillator a deconvolution method was developed. Following the development of the deconvolution method for ATR applications the technique was tested using one-isotope, multi-isotope and fuel simulated sources. Burnup calibrations were perfomed using convoluted and deconvoluted data. The calibrations results showed burnup prediction by this method improves using deconvolution. The final stage of the deconvolution method development was to perform an irradiation experiment in order to create a surrogate fuel source to test the deconvolution method using experimental data. A conceptual design of the fuel scan system is path forward using the rugged LaBr3 detector in an above the water configuration and deconvolution algorithms.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2014

Ranchero Armature Test LA-43-CT-2: PBXN-110 Explosive with no smoothing layer. Lower Slobovia, 6/13/13

This test, documented as LA-43-CT-2, was performed to verify calculations which indicate that the smoothing layer employed for Ranchero Armatures is not required when the slapper point spacing is 18 mm (“On the efficacy of an acrylic layer in the Ranchero armature,” Bob Watt, published in “Ranchero Status Report” LA-14463). [Naming this test –CT-2 acknowledges the previous test performed during 1/11 as the initial test in the series, and we will refer to that test as LA-43-CT-1 in the future.] In addition, higher velocity is achieved when the volume occupied by the smoother is replaced by HE. Two framing cameras were used on the shot, and a 20 point PDV array was fielded to ascertain armature performance in specific conditions. The conclusions are that the armature is smooth enough, and the terminal velocity is increased from ~3.1 mm/μs to ~3.3 mm/μs. The armature tested had casting voids in the HE that were observed in pre-test inspections, and were expected to cause ruptures. (See Appendix 3 of the Ranchero Status Report.) Such “blowouts” were observed in all three locations identified in pre-shot inspection. In addition, ruptures occurred in locations having no pre-shot indication of a problem. These unpredicted blowouts have a difference in appearance from those typically seen. Further visual examination of the inspection radiographs do not reveal the cause, and that is a serious concern for future efforts with such castings. A path forward will include attempting to digitize the inspection x-rays for the charge tested, to see if the cause of the “new” ruptures can be found via computer enhancement. In addition, there are two additional armatures from the same casting lot, and these might also be tested to see if there is some problem with the HE or the armature material in this batch. For now, this plan is on hold, pending the outcome of tests and cost estimates related to using PBX-9501 in place of the PBXN-110. Casting issues would be eliminated in such configurations.

42 ENGINEERING↗
DOE OSTI2014

Electricity Transmission, Pipelines, and National Trails: An Analysis of Current and Potential Intersections on Federal Lands in the Eastern United States, Alaska, and Hawaii

As has been noted in many reports and publications, acquiring new or expanded rights-of-way for transmission is a challenging process, because numerous land use and land ownership constraints must be overcome to develop pathways suitable for energy transmission infrastructure. In the eastern U.S., more than twenty federally protected national trails (some of which are thousands of miles long, and cross many states) pose a potential obstacle to the development of new or expanded electricity transmission capacity. However, the scope of this potential problem is not well-documented, and there is no baseline information available that could allow all stakeholders to study routing scenarios that could mitigate impacts on national trails. This report, Electricity Transmission, Pipelines, and National Trails: An Analysis of Current and Potential Intersections on Federal Lands in the Eastern United States, was prepared by the Environmental Science Division of Argonne National Laboratory (Argonne). Argonne was tasked by DOE to analyze the “footprint” of the current network of National Historic and Scenic Trails and the electricity transmission system in the 37 eastern contiguous states, Alaska, and Hawaii; assess the extent to which national trails are affected by electrical transmission; and investigate the extent to which national trails and other sensitive land use types may be affected in the near future by planned transmission lines. Pipelines are secondary to transmission lines for analysis, but are also within the analysis scope in connection with the overall directives of Section 368 of the Energy Policy Act of 2005, and because of the potential for electrical transmission lines being collocated with pipelines. Based on Platts electrical transmission line data, a total of 101 existing intersections with national trails on federal land were found, and 20 proposed intersections. Transmission lines and pipelines are proposed in Alaska; however there are no locations that intersect national trails. Source data did not indicate any planned transmission lines or pipelines in Hawaii. A map atlas provides more detailed mapping of the topics investigated in this study, and the accompanying GIS database provides the baseline information for further investigating locations of interest. In many cases the locations of proposed transmission lines are not accurately mapped (or a specific route may not yet be determined), and accordingly the specific crossing locations are speculative. However since both national trails and electrical transmission lines are long linear systems, the characteristics of the crossings reported in this study are expected to be similar to both observed characteristics of the existing infrastructure provided in this report, and of the new infrastructure if these proposed projects are built. More focused study of these siting challenges is expected to mitigate some of potential impacts by choosing routes that minimize or eliminate them. The current study primarily addresses a set of screening-level characterizations that provide insights into how the National Trail System may influence the siting of energy transport facilities in the states identified under Section 368(b) of the Energy Policy Act of 2005. As such, it initializes gathering and beginning analysis of the primary environmental and energy data, and maps the contextual relationships between an important national environmental asset and how this asset intersects with energy planning activities. Thus the current study sets the stage for more in-depth analyses and data development activities that begin to solve key transmission siting constraints. Our recommendations for future work incorporate two major areas: (1) database development and analytics and (2) modeling and scenario analysis for energy planning. These recommendations provide a path forward to address key issues originally developed under the Energy Policy Act of 2005 that are now being carried forward under the President’s Climate Action Plan.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2014

Maine Tidal Power Initiative: Environmental Impact Protocols For Tidal Power

The Maine Tidal Power Initiative (MTPI), an interdisciplinary group of engineers, biologists, oceanographers, and social scientists, has been conducting research to evaluate tidal energy resources and better understand the potential effects and impacts of marine hydro-kinetic (MHK) development on the environment and local community. Project efforts include: 1) resource assessment, 2) development of initial device design parameters using scale model tests, 3) baseline environmental studies and monitoring, and 4) human and community responses. This work included in-situ measurement of the environmental and social response to the pre-commercial Turbine Generator Unit (TGU®) developed by Ocean Renewable Power Company (ORPC) as well as considering the path forward for smaller community scale projects.

16 TIDAL AND WAVE POWER↗
DOE OSTI2014

Low Emissions Burner Technology for Metal Processing Industry using Byproducts and Biomass Derived Liquid Fuels (Final Report)

This research and development efforts produced low-emission burner technology capable of operating on natural gas as well as crude glycerin and/or fatty acids generated in biodiesel plants. The research was conducted in three stages (1) Concept definition leading to the design and development of a small laboratory scale burner, (2) Scale-up to prototype burner design and development, and (3) Technology demonstration with field vefiication. The burner design relies upon the Flow Blurring (FB) fuel injection based on aerodynamically creating two-phase flow near the injector exit. The fuel tube and discharge orifice both of inside diameter D are separated by gap H. For H < 0.25D, the atomizing air bubbles into liquid fuel to create a two-phase flow near the tip of the fuel tube. Pressurized two-phase fuel-air mixture exits through the discharge orifice, which results in expansion and breakup of air bubbles yielding a spray with fine droplets. First, low-emission combustion of diesel, biodiesel and straight VO (soybean oil) was achieved by utilizing FB injector to yield fine sprays for these fuels with significantly different physical properties. Visual images for these baseline experiments conducted with heat release rate (HRR) of about 8 kW illustrate clean blue flames indicating premixed combustion for all three fuels. Radial profiles of the product gas temperature at the combustor exit overlap each other signifying that the combustion efficiency is independent of the fuel. At the combustor exit, the NOx emissions are within the measurement uncertainties, while CO emissions are slightly higher for straight VO as compared to diesel and biodiesel. Considering the large variations in physical and chemical properties of fuels considered, the small differences observed in CO and NOx emissions show promise for fuel-flexible, clean combustion systems. FB injector has proven to be very effective in atomizing fuels with very different physical properties, and it offers a path forward to utilize both fossil and alternative liquid fuels in the same combustion system. In particular, experiments show that straight VO can be cleanly combusted without the need for chemical processing or preheating steps, which can result in significant economic and environmental benefits. Next, low-emission combustion of glycerol/methane was achieved by utilizing FB injector to yield fine droplets of highly viscous glycerol. Heat released from methane combustion further improves glycerol pre-vaporization and thus its clean combustion. Methane addition results in an intensified reaction zone with locally high temperatures near the injector exit. Reduction in methane flow rate elongates the reaction zone, which leads to higher CO emissions and lower NOx emissions. Similarly, higher air to liquid (ALR) mass ratio improves atomization and fuel pre-vaporization and shifts the flame closer to the injector exit. In spite of these internal variations, all fuel mixes of glycerol with methane produced similar CO and NOx emissions at the combustor exit. Results show that FB concept provides low emissions with the flexibility to utilize gaseous and highly viscous liquid fuels, straight VO and glycerol, without preheating or preprocessing the fuels. Following these initial experiments in quartz combustor, we demonstrated that glycerol combustion can be stably sustained in a metal combustor. Phase Doppler Particle Analyzer (PDPA) measurements in glycerol/methane flames resulted in flow-weighted Sauter Mean Diameter (SMD) of 35 to 40 μm, depending upon the methane percentage. This study verified that lab-scale dual-fuel burner using FB injector can successfully atomize and combust glycerol and presumably other highly viscous liquid fuels at relatively low HRR (<10 kW). For industrial applications, a scaled-up glycerol burner design thus seemed feasible.

03 NATURAL GAS↗
DOE OSTI2014

Actinide Studies with Ultracold Neutrons [Slides]

First characterization of UCN-induced fission: • Previously no fission data at these energies • Initial characterizations of UCN energy dependence, material thickness. First observation of sputtering from UCN-induced fission: • Proof of principle demonstrated • Analysis of sputtered rates, angular and size distribution underway. Future plans: • Determine absolute cross sections • Develop scheme for characterizing ejected material • Explore effect of material thickness, surface preparation in more detail • Develop path forward for plutonium and other actinides.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2014

Light Water Reactor Sustainability Program: BWR High-Fluence Material Project: Assessment of the Role of High-Fluence on the Efficiency of HWC Mitigation on SCC Crack Growth Rates

As nuclear power plants age, the increasing neutron fluence experienced by stainless steels components affects the materials resistance to stress corrosion cracking and fracture toughness. The purpose of this report is to identify any new issues that are expected to rise as boiling water reactor power plants reach the end of their initial life and to propose a path forward to study such issues. It has been identified that the efficiency of hydrogen water chemistry mitigation technology may decrease as fluence increases for high-stress intensity factors. This report summarizes the data available to support this hypothesis and describes a program plan to determine the efficiency of hydrogen water chemistry as a function of the stress intensity factor applied and fluence. This program plan includes acquisition of irradiated materials, generation of material via irradiation in a test reactor, and description of the test plan. This plan offers three approaches, each with an estimated timetable and budget.

36 MATERIALS SCIENCE↗
DOE OSTI2014

ARIES Oxide Production Program Monthly Report – April 2014

A summary of the accomplishments, milestones, financial summary, project performance and issues facing the Oxide Production Program for the end of April 2014 is presented in this Executive Summary. PF-4 and ARIES operations remain paused in order to resolve issues and perform an extent-of-condition review for Criticality Safety and Conduct of Operations. On April 28th, Jeff Yarbrough issued a memorandum updating status on the “pause” of PF-4 programmatic operations. He reported that 150 of the procedures that control programmatic operations in PF-4 have successfully resumed. These 150 procedures represent about ½ of the total that will enable us to meet FY14 programmatic commitments. No formal letter of direction will be provided to LANS via the NNSA Field Office contracting officer to address the direction relative to shipments, analytical chemistry sampling and guidance for financial adjustments in FY14 and FY15. LANS will provide a revised plan based on the funding profile included in the President’s Budget Request for the remainder of FY14 and FY15 to include revised FY14 milestones and proposed FY15 milestones. The ARIES Pit Cutter project met the NNSA milestone (Complete Design of Simple Pit Disassembly Equipment [ARIES Pit Cutter] – Due 8/15/14) by completing the fabrication design on 4/3/14, well in advance of the 8/15/14 due date. The project team has started procurement of long-lead items in preparation of the prototype fabrication and cold testing. The fabrication is scheduled to complete in FY14 and the cold testing will begin in FY14 and complete in early FY15. LANL and PNNL met on April 14 to discuss the path forward for PNNL criticality support to the program. The consensus was that PNNL resources can be effectively applied to the generation of detailed CSEs to support the program independent of the current ESS strategy. FY15 program planning is underway. The team is working on planning/drafting the work packages and developing the schedule under the assumption that operations will begin October 1, 2014. A planning schedule has been finalized and the team is meeting regularly to discuss details at the work package and WBS levels. The FY15 PMP is also in the process of being updated. The goal is to have all the drafts reviewed/approved and finalized prior to the start of the FY. MQ personnel have completed ADPSM Management Assessment: Evaluate Quality Roles and Responsibility Agreements between ADPSM and LANL Technical Support Organizations (PFITS 2011-1943). Two findings and four opportunities for improvement were reported. The robotic lathe controller upgrade has entered the construction phase of the project. The controller cabling IWD pre-job meeting was completed. The initial robotic lathe functional test was completed. The existing controller power supply disconnect is scheduled for early May. The NDA Cage project team received notification on 3/28/14 to restart the NDA cage project. Since then the team have been busy with activities that include assigning a planner, getting the construction work package ready for construction and getting the USQ completed. The electrical services installation for the new welding skid for the Inner Can Welder was completed. A gas bottle rack, used to support welding operations, will be installed in early May. The Outer Can Welder design is complete and the IWD is in development to execute construction. Installation materials have been ordered. Work continues on the MD-2 preliminary design. The project engineer is performing a technical evaluation of the Project Management Plan that was submitted by the design agent in response to the LANL Request for Proposal. If all requirements have been captured, LANL procurement will develop a contract and give the design agent notice to proceed on the preliminary design. Estimated completion is scheduled for September 2014. The design for the TA-55 Bldg. 314 warehouse was issued at 90% complete and has begun the last review process. A constructability review is scheduled for early May. The Project Manager has been working with the LANL estimating group to get the class 3 estimate for review. The Oxide Production Cage Upgrade project has kicked-off efforts on the 30% design. Requirements documentation has been drafted. The floor space was walked-down with other project managers and stakeholders and the boundaries were agreed upon.

ARIES↗
DOE OSTI2014

Pentachart: From the Earth’s Core to the Cosmos

The pentachart consists of a three-panel chart illustrating points in the following areas: Background and Motivation; Innovation; Description; Anticipated Impact; and Path Forward.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2014

Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development.

We present the results of an LDRD project to develop diagnostics to perform fundamental measurements of material properties during shock compression of condensed phase materials at micron spatial scales and picosecond time scales. The report is structured into three main chapters, which each focus on a different diagnostic devel opment effort. Direct picosecond laser drive is used to introduce shock waves into thin films of energetic and inert materials. The resulting laser - driven shock properties are probed via Ultrafast Time Domain Interferometry (UTDI), which can additionally be used to generate shock Hugoniot data in tabletop experiments. Stimulated Raman scattering (SRS) is developed as a temperature diagnostic. A transient absorption spectroscopy setup has been developed to probe shock - induced changes during shock compressio n. UTDI results are presented under dynamic, direct - laser - drive conditions and shock Hugoniots are estimated for inert polystyrene samples and for the explosive hexanitroazobenzene, with results from both Sandia and Lawrence Livermore presented here. SRS a nd transient absorption diagnostics are demonstrated on static thin - film samples, and paths forward to dynamic experiments are presented.

Kearney, Sean Patrick↗
DOE OSTI2014

Time-Domain Reflectometry for Tamper Indication in Unattended Monitoring Systems for Safeguards

The International Atomic Energy Agency (IAEA) continues to expand its use of unattended, remotely monitored measurement systems. An increasing number of systems and an expanding family of instruments create challenges in terms of deployment efficiency and the implementation of data authentication measures. Pacific Northwest National Laboratory (PNNL) leads a collaboration that is exploring various tamper-indicating (TI) measures that could help to address some of the long-standing detector and data-transmission authentication challenges with IAEA’s unattended systems. PNNL is investigating the viability of active time-domain reflectometry (TDR) along two parallel but interconnected paths: (1) swept-frequency TDR as the highly flexible, laboratory gold standard to which field-deployable options can be compared, and (2) a low-cost commercially available spread-spectrum TDR technology as one option for field implementation. This report describes PNNL’s progress and preliminary findings from the first year of the study, and describes the path forward.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗