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Sandia National Laboratories FY21 Progress Report

Aguirre, Brandon A.

The Energetic Neutrons campaign led by Sandia National Laboratories (SNL) had a successful year testing electronic devices and printed circuit boards (PCBs) under 14 MeV neutron irradiation at OMEGA. During FY21 Sandia’s Neutron Effects Diagnostics (NEDs) and data acquisition systems were upgraded to test novel commercial off-the-shelf and Sandia-fabricated electronic components that support SNL’s National Security mission. The upgrades to the Sandia platform consisted of new cable chains, sample mount fixtures and a new fiber optics platform for testing optoelectronic devices.

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Transmitted wave measurements in cold sprayed materials under dynamic compression

Mccoy, Chad A.; Branch, Brittany A.; Vackel, Andrew

Spray-formed materials have complex microstructures which pose challenges for microscale and mesoscale modeling. To constrain these models, experimental measurements of wave profiles when subjecting the material to dynamic compression are necessary. The use of a gas gun to launch a shock into a material is a traditional method to understand wave propagation and provide information of time-dependent stress variations due to complex microstructures. This data contains information on wave reverberations within a material and provides a boundary condition for simulation. Here we present measurements of the wavespeed and wave profile at the rear surface of tantalum, niobium, and a tantalum/niobium blend subjected to plate impact. Measurements of the Hugoniot elastic limit are compared to previous work and wavespeeds are compared to longitudinal sound velocity measurements to examine wave damping due to the porous microstructure.

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Design Guidelines for Deployable Wind Turbines for Military Operational Energy Applications

Naughton, Brian; Jimenez, Tony; Preus, Robert; Summerville, Brent; Whipple, Bradley; Reen, Dylan; Gentle, Jake; Lang, Eric

This document aims to provide guidance on the design and operation of deployable wind systems that provide maximum value to missions in defense and disaster relief. Common characteristics of these missions are shorter planning and execution time horizons and a global scope of potential locations. Compared to conventional wind turbine applications, defense and disaster response applications place a premium on rapid shipping and installation, short-duration operation (days to months), and quick teardown upon mission completion. Furthermore, defense and disaster response applications are less concerned with cost of energy than conventional wind turbine applications. These factors impart design drivers that depart from the features found in conventional distributed wind turbines, thus necessitating unique design guidance. The supporting information for this guidance comes from available relevant references, technical analyses, and input from industry and military stakeholders. This document is not intended to be a comprehensive, prescriptive design specification. This document is intended to serve as a written record of an ongoing discussion of stakeholders about the best currently available design guidance for deployable wind turbines to help facilitate the effective development and acquisition of technology solutions to support mission success. The document is generally organized to provide high-level, focused guidance in the main body, with more extensive supporting details available in the referenced appendices. Section 2 begins with a brief qualitative description of the design guidelines being considered for the deployable wind turbines. Section 3 provides an overview of the characteristics of the mobile power systems commonly used in U.S. military missions. Section 4 covers current military and industry standards and specifications that are relevant to a deployable wind turbine design. Section 5 presents the deployable turbine design guidelines for the application cases.

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Soot Predictions with a Laminar Flamelet Combustion Model in SIERRA/Fuego on a Coflow Scenario

Kurzawski, Andrew J.; Hansen, Michael A.; Hewson, John C.

This report describes an assessment of flamelet based soot models in a laminar ethylene coflow flame with a good selection of measurements suitable for model validation. Overall flow field and temperature predictions were in good agreement with available measurements. Soot profiles were in good agreement within the flame except for near the centerline where imperfections with the acetylene-based soot-production model are expected to be greatest. The model was challenged to predict the transition between non-sooting and sooting conditions with non-negligible soot emissions predicted even down to small flow rates or flame sizes. This suggests some possible deficiency in the soot oxidation models that might alter the amount of smoke emissions from flames, though this study cannot quantify the magnitude of the effect for large fires.

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Exploring Explicit Uncertainty for Binary Analysis (EUBA)

Leger, Michelle A.; Darling, Michael C.; Jones, Stephen T.; Matzen, Laura E.; Stracuzzi, David J.; Wilson, Andrew T.; Bueno, Denis; Christentsen, Matthew; Ginaldi, Melissa; Bays, Nathan R.; Heidbrink, Scott J.; Howell, Breannan C.; Leger, Chris; Reedy, Geoffrey; Rogers, Alisa; Williams, Jack

Reverse engineering (RE) analysts struggle to address critical questions about the safety of binary code accurately and promptly, and their supporting program analysis tools are simply wrong sometimes. The analysis tools have to approximate in order to provide any information at all, but this means that they introduce uncertainty into their results. And those uncertainties chain from analysis to analysis. We hypothesize that exposing sources, impacts, and control of uncertainty to human binary analysts will allow the analysts to approach their hardest problems with high-powered analytic techniques that they know when to trust. Combining expertise in binary analysis algorithms, human cognition, uncertainty quantification, verification and validation, and visualization, we pursue research that should benefit binary software analysis efforts across the board. We find a strong analogy between RE and exploratory data analysis (EDA); we begin to characterize sources and types of uncertainty found in practice in RE (both in the process and in supporting analyses); we explore a domain-specific focus on uncertainty in pointer analysis, showing that more precise models do help analysts answer small information flow questions faster and more accurately; and we test a general population with domain-general sudoku problems, showing that adding "knobs" to an analysis does not significantly slow down performance. This document describes our explorations in uncertainty in binary analysis.

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Gen 3 Particle Pilot Plant (G3P3) -- High-Temperature Particle System for Concentrating Solar Power (Phases 1 and 2)

Ho, Clifford K.; Sment, Jeremy N.I.; Albrecht, Kevin; Mills, Brantley; Schroeder, Nathaniel R.

The U.S. Department of Energy Solar Energy Technologies Office initiated the Generation 3 Concentrating Solar Power (CSP) program to achieve higher operating temperatures (>700 °C) to enable next-generation CSP high-temperature power cycles such as the supercritical CO2 (sCO2) Brayton Cycle. Three teams were selected to pursue high-temperature gas, liquid, and solid pathways for the heat-transfer media. Phases 1 and 2, which lasted from 2018 – 2020, consisted of design, modeling, and testing activities to further de-risk each of the technologies and develop a design for construction, commissioning, and operation of a pilot-scale facility in Phase 3 (2021 – 2024). This report summarizes the activities in Phases 1 and 2 for the solid-particle pathway led by Sandia National Laboratories. In Phases 1 and 2, Sandia successfully de-risked key elements of the proposed Gen 3 Particle Pilot Plant (G3P3) by improving the design, operation, and performance of key particle component technologies including the receiver, storage bins, particle-to-sCO2 heat exchanger, particle lift, and data acquisition and controls. Modeling and testing of critical components have led to optimized designs that meet desired performance metrics. Detailed drawings, piping and instrumentation diagrams, and process flow diagrams were generated for the integrated system, and structural analyses of the assembled tower structure were performed to demonstrate compliance with relevant codes and standards. Instrumentation and control systems of key subsystems were also demonstrated. Together with Bridgers & Paxton, Bohannan Huston, and Sandia Facilities, we have completed a 100% G3P3 tower design package with stamped engineering drawings suitable for construction bid in Phase 3.

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Simultaneous Imaging of Molecular Rovibrational Nonequilibrium, Reactive Species, and Electric Field for Plasma-Assisted Chemistry

Kliewer, Christopher J.; Vorenkamp, Madeline; Ju, Yiguang

The Sandia-PRF has built a new capability for the low-temperature plasma community for the simultaneous imaging of molecular rotation/vibration nonequilibrium, electric field, and the distribution of OH radical and formaldehyde in reactive low temperature plasma systems. The system is currently investigating the plasma-assisted deflagration to detonation transition in a micro-combustor channel.

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A Medium Frequency RF Sensor for Detection of Magnetized Quark Nuggets

Borchardt, John

It is hypothesized that dark matter is composed of particles called quark nuggets, and further that these particles have a permanent magnetic dipole moment. If this hypothesis is true, calculations predict that a magnetized quark nugget (MQN) will oscillate when encountering the Earth's magnetosphere, and emit RF radiation between 30kHz and 30MHz. To support testing this hypothesis, a loop antenna sensor was designed and developed, which is described in this report. This sensor operates between 300kHz and 3MHz and achieves about -11dBfT/vHz sensitivity at 1.5MHz.

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2020 Energy Storage Pricing Survey

Baxter, Richard

The annual Energy Storage Pricing Survey (ESPS) series is designed to provide a standardized reference system price for various energy storage technologies across a range of different power and energy ratings. This is an essential first step in comparing systems of the different technologies’ usage costs and total cost of ownership. The final system prices are developed based on data from an extensive set of interviews with representatives across the manufacturing and project development value chain, plus available published data. This information is incorporated into a consistent methodology structure that will allow pricing information to be incorporated at whatever level it was obtained, ranging from component to fully installed system. The ESPS system pricing methodology breaks down the cost of an energy storage system into the following component categories: the storage module; the balance of system; the power conversion system; the energy management system; and the engineering, procurement, and construction costs. By evaluating each of the different component costs separately, a more accurate system cost can be developed that provides internal pricing consistency between different project sizes using the same technology, as well as between different technologies that utilize similar components.

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Solar Performance Insight (Final Report)

Hansen, Clifford

The PV Operations and Maintenance (O&M) service industry lacks an affordable, well-documented, intuitive PV modeling and analytics tool to calculate modeled performance from actual data from multiple data acquisition systems (DAS). We envision a performance modeling and analytics platform built on open-source, extensible, community-maintained code. The key innovation is the community-driven development of pvlib python delivered through a lightweight web service to provide configurable, consistent and reproducible PV modeling for O&M providers.

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Results 11251–11300 of 101,000
Results 11251–11300 of 101,000
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