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Activities for most tasks continued smoothly from FY19 into FY20. A Science Plan was developed for the F2019 Nuclear Forensics Venture in Q1, and was presented at HQ on Jan17, 2020. The Science plan included input from all tasks in the F2019 Venture plus this project, and was assembled and presented jointly by all three labs.
After receiving funds at the beginning of FY21 we were able to resume work on the project. We continued data analysis of 156 Eu decay. The project has also gone through an Independent Review in November. Following the previously reported steps in the analysis of 156 Eu, specifically removing random coincidences from the gamma ray spectrum, we look not only at the peak of interest (811 keV) but all other gamma rays that are visible. Determining the area of all gamma ray peaks in this random coincidence free spectrum is not only necessary to calculate the gamma ray branching ratios but combined with the peak areas of the gamma ray singles spectrum we are able to determine experimentally the efficiency of the beta detector.
This document details the computational fluid dynamic and system-level modeling, including a mechanistic representation of a Terry turbopump. Until this recent effort, data and modeling results show that a Terry turbine, flowing air (or steam) at a certain rate, can develop the same power at two very different speeds, and has large implications with respect to understanding how a boiling water reactor's reactor core isolation cooling system or a pressurized water reactor turbine driven auxiliary feedwater system would respond to a loss of electrical power for Terry turbine speed governing. This work has provided insights in modeling uncertainties and provides confirmation for experimental efforts for the Terry turbopump expanded operating band being conducted at Texas A&M University.
ParaChoice supports the VTO mission using early-stage research to help in the development of technology that will improve affordability of transportation, while encouraging innovation and reducing dependence on petroleum. Analysis with the ParaChoice model enables exploration of key factors that influence consumer choice, and technology, fuel, and infrastructure development for the vehicle mix. Because of the distinct differences between requirements, needs, and use patterns for light duty vehicles (LDVs) relative to heavy duty vehicles (HDVs), this project models the dynamics of each of these segments to characterize the factors that influence technology adoption.
Regulatory drivers and market demands for lower pollutant emissions, lower carbon dioxide emissions, and lower fuel consumption motivate the development of clean and fuel-efficient engine operating strategies. Most current production engines use a combination of both in-cylinder and exhaust emission control strategies to achieve these goals. The emissions and efficiency performance of in-cylinder strategies depend strongly on flow and mixing processes associated with fuel injection. Both heavy- and light-duty engine/vehicle manufacturers use multiple-injection strategies to reduce noise, emissions, and fuel consumption. For both conventional and low-temperature diesel combustion, the state of knowledge and modeling tools for multiple injections are far less advanced than for single-injection strategies. Engine efficiency is limited to some degree by tradeoffs that must be accepted to meet particulate matter (including soot) emissions limits. Recent work on this project has filled some knowledge gaps on soot oxidation with multiple injections, and the current work for Fiscal Year (FY) 2018 addresses knowledge gaps on soot formation for multiple injections. While total in-cylinder soot is readily measured, discerning formation from oxidation is difficult. The FY 2018 experiments are designed to create in-cylinder conditions at the threshold of soot formation, where processes that affect soot formation can be more readily discerned. Soot formation pathways under such conditions are fraught with uncertainties, and soot models significantly overpredict polyaromatic hydrocarbon (PAH) and soot, so experimental data at these conditions will provide much needed data for improvements to PAH and soot models.
The Spent Fuel and Waste Science and Technology (SFWST) Campaign of the U.S. Department of Energy Office of Nuclear Energy, Office of Spent Fuel and Waste Disposition (SFWD), has been conducting research and development on generic deep geologic disposal systems (i.e., geologic repositories). This report describes specific activities in fiscal year (FY) 2019 associated with FY19 Geologic Disposal Safety Assessment (GDSA) Repository Systems Analysis (RSA) work package within the SFWST Campaign. The overall objective of the GDSA RSA work package is to develop generic deep geologic repository concepts and system performance assessment (PA) models in several host-rock environments, and to simulate and analyze these generic repository concepts and models using the GDSA Framework toolkit, and other tools as needed.
Traditional batteries are composed of two-dimensional films that are stacked and/or rolled. Thin film batteries display high power density while their thick film counterparts show good energy density, but it has proven difficult to concurrently achieve both within these planar form factors. In addition, conventional Li-ion batteries based on liquid organic electrolytes or gel polymer electrolytes have raised severe safety concerns due to the intrinsic flammable properties of the organic electrolytes.
Abstract not provided.
The National Nuclear Security Agency (NNSA) initiated the Minority Serving Institution Partnership Plan (MSIPP) to 1) align investments in a university capacity and workforce development with the NNSA mission to develop the needed skills and talent for NNSA’s enduring technical workforce at the laboratories and production plants, and 2) to enhance research and education at under-represented colleges and universities. Out of this effort, MSIPP launched a new consortium in early FY17 focused on Tribal Colleges and Universities (TCUs) known as the Advanced Manufacturing Network Initiative (AMNI). This consortium has been extended for FY20 and FY21. The following report summarizes the status update during this quarter.
The current one-year allocation (w20 qburst) is the first year in a two year allocation of the same name. The project has supported two publications in peer-review journals, another manuscript in preparation for publication, a white paper for the Astro2020 Decadal Survey, and a number of talks (see below). Code development continues on implementing a neutrino quantum kinetic equation solver into BURST, now called QBURST. While implementing coherent and forward-scattering processes into the dynamical neutrino evolution equations, multiple numerical issues have appeared. We have remedied a number of these issues through extensive debugging and testing, which include streamlining interpolation and implementing new ODE integration techniques. Further testing is required to solve the problem at a precision of better than one part in 10 6 . We expect that we will understand the numerical difficulties and implement solutions by end of year 2021.
This research is focused on applying the NLem method to the full thermal radiative transfer (TRT) equations in the context of a Monte Carlo solution strategy. A framework has been developed for obtaining a solution to the TRT equations using the nonlinear elimination method (NLem) method. Current efforts are focused of the development and verification of the required Monte Carlo algorithm, diffusion algorithm, and material energy solver. Once all three pieces have been verified, the algorithms will then be coupled into a fully functioning method for applying NLem to the TRT equations.
Several 100 μg aliquots of NBL CRM 137 Pu sulfate tetrahydrate were prepared in 20 mL glass vials at some time in the past and are expected to have similar chemical composition and similar concentrations of contaminants as the bulk 250 mg CRM 137 Pu sulfate tetrahydrate units. Thus, these units were characterized and used to test Pu purification chemistry to be employed on the larger unit. For preliminary characterization, the residue of bottle 6 was dissolved in 4 M HNO3/0.01 M HF and transferred quantitatively to a pre-weighed 30 mL Savillex Teflon vial with a total solution mass of approximately 18 g. A gravimetric aliquot was removed from this solution for characterization and the remaining solution was dried down and reconstituted in 8 M HNO 3 to test the anion exchange purification column.
Abstract not provided.
The Advanced Technology Development and Mitigation (ATDM) program at Sandia National Laboratories is a new effort to build next-generation simulation codes that will map well to upcoming exascale computing platforms. Rather than follow traditional single- program, multiple data (SPMD) programming techniques, ATDM is developing applications in an asynchronous many task (AMT) form that describes work as a graph of tasks that have data dependencies. The data management team is focused on developing a data warehouse for ATDM that will enable tasks to store and exchange data objects efficiently. This report summarizes the data management teams efforts during FY15, and documents: (1) an initial API and implementation for the data warehouses key/value store, (2) API requirements for use with ATDMs runtime, (3) initial requirements for storing ATDM-specific data, and (4) the current organization of software components that will be used by the data warehouse.
The 95 Zr manuscript describing our experimental approach to measure branching ratios of long-lived fission products has been completed and successfully published in NIM A. This article is an important milestone in this effort and will serve as a great reference in any future reports describing results of other measurements we plan to perform. We have also expended our team, and Daniel Hoff joined us as a postdoc. We have been training him on how to use our analysis and simulation tools, as well as bringing him up to speed on the technical details of our experiment.
Three ferritic/martensitic alloys; F82H, Fe8Cr2W and CNA3 were studied for the effect of H and He on swelling. Single ion beam (Fe 2+ ), dual ion beam (Fe 2+ +He 2+ ), and triple ion beam (Fe 2+ +He 2+ +H + ) irradiations were conducted at 500°C to a damage level of 50 dpa and dual and triple beam irradiation experiments were conducted at 450°C to 50 dpa. Cavity distribution and swelling were comparable in dual ion beam and triple ion beam irradiated F82H at 500°C, indicating that the role of hydrogen in swelling in triple beam irradiated F82H appeared to be insignificant compared to the role of helium. Swelling in Fe8Cr2W and CNA3 at 500°C was approximately 3-4X greater than that at 450°C. In F82H, the average cavity size and swelling were minimally larger at 500°C than at 450°C. The significant role of hydrogen in swelling has yet to be confirmed. Future efforts will focus on separate effects experiments to understand the role of hydrogen in cavity swelling.
Abstract not provided.
Real-time, in-situ, high spatial resolution (sub-cm) imaging of the near-borehole environment would revolutionize wellbore diagnostics and integrity assessment by direct observation of defects. It is becoming increasingly apparent, that better understanding of the near-wellbore environment is required to meet the safety and operational needs in challenging environments such as those present in subsurface energy extraction (geothermal) and storage (CO2 sequestration) applications. Therefore, it is important to have a more robust ability to image the near-borehole and reliably detect defects. It was proposed to further develop and improve our advanced 3D imaging system to evaluate casing defects (e.g. corrosion) and cement quality in either open- or cased-borehole with the ultimate goal to develop a commercially deployable technology. The system consists of a unique acoustic source (LANL) and advanced inversion techniques for image processing (LANL, ORNL). This system will provide comprehensive borehole integrity monitoring with improved resolution over existing techniques. As an application of this imaging system, we will characterize the effectiveness of next-generation wellbore completion technology (NETL, SNL), and will demonstrate that, unlike current technology, the proposed approach can successfully characterize foamed cements.