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Plate Impact and Penetration at the Ballistic Launch Tube: Experiments

Yeh, Peter D.; Donahue, Emily D.; Miller, Timothy J.; Payne, Lloyd R.; Korbin, John P.; Teeter, Russell D.

This report details the data collected from plate impact experiments performed at the Ballistics Launch Tube (BLT) in May 2019. The experiments consisted of 62 shots of copper projectiles (cylindrical and ogive) impacting 1/4", 1/2", and 3/4" aluminum plates at varying velocities. An additional 14 shots of copper cylinders on a 1" steel plate were fired at varying velocities as a Taylor anvil test. We recorded videos of the impact events and resulting fragmentation using a multi-view system of three high speed cameras. The purpose of these tests was to collect high quality data from the multi-view camera system and create digital representations of the deformed target, projectile and fragments. This data is intended to be used as validation data set for high fidelity simulation codes. This report covers the experimental setup, diagnostics, and collected data. Data processing and analysis are underway and will be discussed in a separate report.

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The Gulf Nuclear Energy Infrastructure Institute (GNEII): Origins, Objectives, and Operations—A Joint Report

Williams, Adam D.; Solodov, Alexander A.; Mohagheghi, Amir H.; Beeley, Philip A.; Al-Ameri, Saeed

The Gulf Nuclear Energy Infrastructure Institute (GNEII—pronounced "genie") seeks to develop expertise among future leaders of Gulf-region nuclear power programs in global standards, norms and best practices in nuclear energy programs. More specifically, the institute aims to contribute to the enhancement of nuclear security, safety, and safeguards (the so-called nuclear "3S") by providing an avenue for regional nuclear interaction, technical collaboration, lessons-learned discussions, and best-practices sharing. It is a multidisciplinary human capacity development institute offering education, research and technical services to support responsible nuclear energy programs in the Gulf and Middle East regions. In this Joint Report, Chapter 2 discusses GNEII's origins (including drivers, milestones, and design principles), Chapter 3 discusses GNEII's objectives (including goals, mission, and vision), Chapter 4 discusses GNEII's operations (including education, research, and technical service pillars), Chapter 5 discusses major insights and next steps, and Chapter 6 provides a list of publications offering additional depictions and details of GNEII's evolution. Though only one piece of a multi-faceted, multi-national effort to develop human infrastructure needs for nascent nuclear energy programs, GNEII offers a model that addresses the socio-technical attributes of nuclear 3S that can be replicated globally.

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High Temperature and Power Dependent Photoluminescence Analysis on Commercial Lighting and Display LED Materials for Future Power Electronic Modules

Scientific Reports

Sabbar, Abbas; Madhusoodhanan, Syam; Al-Kabi, Sattar; Dong, Binzhong; Wang, Jiangbo; Atcitty, Stanley A.; Kaplar, Robert K.; Ding, Ding; Mantooth, Alan; Yu, Shui Q.; Chen, Zhong

Commercial light emitting diode (LED) materials - blue (i.e., InGaN/GaN multiple quantum wells (MQWs) for display and lighting), green (i.e., InGaN/GaN MQWs for display), and red (i.e., Al0.05Ga0.45In0.5P/Al0.4Ga0.1In0.5P for display) are evaluated in range of temperature (77–800) K for future applications in high density power electronic modules. The spontaneous emission quantum efficiency (QE) of blue, green, and red LED materials with different wavelengths was calculated using photoluminescence (PL) spectroscopy. The spontaneous emission QE was obtained based on a known model so-called the ABC model. This model has been recently used extensively to calculate the internal quantum efficiency and its droop in the III-nitride LED. At 800 K, the spontaneous emission quantum efficiencies are around 40% for blue for lighting and blue for display LED materials, and it is about 44.5% for green for display LED materials. The spontaneous emission QE is approximately 30% for red for display LED material at 800 K. The advance reported in this paper evidences the possibility of improving high temperature optocouplers with an operating temperature of 500 K and above.

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2018 Energy Storage Pricing Survey

Baxter, Richard

Since grid energy storage is still a nascent industry, it is often difficult to obtain capital costs for various energy storage technologies. This type of information is required to perform an initial cost-benefit analysis related to a potential energy storage deployment, as well as to compare different energy storage technology options. The goal of this report is to summarize energy storage capital costs that were obtained from industry pricing surveys. The methodology breaks down the cost of an energy storage system into the following categories: the storage module; the balance of system; the power conversion system; the energy management system; and the engineering, procurement, and construction costs. Pricing data is presented for the following technologies: pumped hydro storage; compressed air energy storage; sodium battery storage; zinc battery storage; long duration flywheels; short duration flywheels; vanadium flow batteries; zinc bromide flow batteries; iron flow batteries; nickel batteries; lithium ion energy batteries; lithium ion power batteries; lead acid batteries; and advanced lead carbon batteries.

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A Domain-Specific Language for High-Consequence Control Software

Hulette, Geoffrey C.; Armstrong, Robert C.

While most software development for control systems is directed at what the system is supposed to do (i.e., function), high-consequence controls must account for what the system is not supposed to do (i.e., safety, security and reliability requirements). A Domain Specific Language (DSL) for high-consequence digital controls is proposed. As with similar tools for the design of controls, the DSL will have plug-in modules for common controller functions. However, the DSL will also augment these modules with attendant "templates" that aid in the proof of safety, security and reliability requirements, not available in current tools. The object is to create a development methodology that makes construction of high-assurance control systems as easy as controls that are designed for function alone.

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Hydrogen diffusion across interfaces in zirconium

Jones, Reese E.; Reyes, Royce; Zhou, Xiaowang Z.; Foster, Michael E.; Spataru, Dan C.; Spearot, Doug E.

In order to study the effects of Ni oxidation barriers on H diffusion in Zr, a Ni-Zr-H potential was developed based on an existing Ni-Zr potential. Using this and existing binary potentials H diffusion characteristics were calculated and some limited findings for the performance of Ni on Zr coatings are made.

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Sodium Fire Collaborative Study Progress (CNWG FY 2019)

Laros, James H.; Uchibori, Akihiro

This report discusses the progress on the collaboration between Sandia National Laboratories (Sandia) and Japan Atomic Energy Agency (JAEA) on the sodium fire research in fiscal year 2019. First, the current sodium pool fire model in MELCOR, which is adapted from CONTAIN-LMR code, is discussed. The associated sodium fire input requirements are also presented. A proposed model improvement developed at Sandia is discussed. Finally, the validation study of the sodium pool fire model in MELCOR carried out by a JAEA's staff is described. To validate this model, a JAEA sodium pool fire experiment (F7-1 test) is used. A preliminary calculation is performed using a modified MELCOR model from a previous experiment simulation. The results of the calculation are discussed as well as suggestions for improvement. Finally, recommendations are made for new MELCOR simulations for next fiscal year, 2020.

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Radiation and Self Heating Effects in Hetero-Junction Bipolar Transistors (FY2019 L2 MileStone 6723 Report)

Hembree, Charles E.; Robertson, Perry J.

Hetero-Junction Bipolar Transistors (HBT) have several advantages over Silicon Bipolar Junction Transistors (BJT) in radiation environments. One advantage is an intrinsic hardness to displacement damage causing radiation. The generally smaller size of HBTs compared to BJTs also means that less photocurrent is generated by these devices. A disadvantage of the smaller size is less ability to dissipate heat due to smaller surface areas and contacts. This report describes simulations intended to study the initial heating of HBT transistors due to ionizing radiation events and the subsequent heating caused by feedback in the devices when responding to these events.

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2020 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base

Griffith, Stacy R.

The 2020 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base has been prepared in accordance with the "Letter of Agreement Between Department of Energy, National Nuclear Security Administration, Sandia Field Office (DOE/NNSA/SFO) and 377th Air Base Wing (ABW), Kirtland Air Force Base (KAFB) for Terrestrial Sampling" (signed January 2017), Sandia National Laboratories, New Mexico (SNL/NM). The Letter of Agreement requires submittal of an annual terrestrial sampling plan.

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TICTOC: Compact Atomic Clock with Integrated Photonics

Ivory, Megan K.; Gehl, M.; Setzer, William J.; McGuinness, Hayden J.; Haltli, Raymond A.; Blain, Matthew G.; Stick, Daniel L.; Parazzoli, Lambert P.

Atomic clocks are precision timekeeping devices that form the basis for modern communication and navigation. While many atomic clocks are room-sized systems requiring bulky free space optics and detectors, the Trapped-lon Clock using Technology-On-Chip (TICTOC) project integrates these components into Sandia's existing surface trap technology via waveguides for beam delivery and avalanche photodiodes for light detection. Taking advantage of a multi-ensemble clock interrogation approach, we expect to achieve record time stability (< 1 ns error per year) in a compact (< /1 2 L) clock. Here, we present progress on the development of the integrated devices and recent trapped ion demonstrations.

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Low frequency stable and accurate potential-based time domain integral equations for dielectric regions

2019 Photonics and Electromagnetics Research Symposium - Fall, PIERS - Fall 2019 - Proceedings

Roth, Thomas E.; Chew, W.C.

Potential-based formulations are new approaches gaining interest for deriving computational electromagnetics methods that perform markedly better for low frequencies and complicated structures (e.g., subwavelength and multiscale geometries) compared to traditional field-based formulations. Further, these methods are also more directly applicable to coupling into quantum physics problems that are becoming more prevalent in engineering applications. These methods derive their improved performance by developing systems to be discretized directly in terms of the magnetic vector potential and electric scalar potential, which are deemed more fundamental quantities for quantum applications than the electric and magnetic fields. Performing derivations in this way has resulted in equations that can accurately capture both wave physics (where the electric and magnetic fields are tightly coupled) and quasistatic phenomena (where the electric and magnetic fields become increasingly uncoupled) at the same time. This work focuses on continuing the development of time domain integral equations (TDIEs) based on the potential-based formulation to meet the demanding bandwidth requirements needed to efficiently analyze a wide range of quantum electromagnetic physics. Past work on potential-based TDIEs were applicable to perfect electrically conducting objects, and were shown to be stable and accurate over broad frequency ranges. More recently, initial efforts at developing potential-based TDIEs for dielectric regions were introduced. However, these initial equations did not exhibit the low frequency accuracy and stability properties desired from this formulation. This work demonstrates a new set of TDIEs that overcome the limitations of the original formulation, achieving high accuracy and good stability at analyzing dielectric objects at very low frequencies. These properties of the improved formulation are demonstrated through numerical results.

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Historical Examination of the ASTM Standard E722 1-MeV Silicon Equivalent Fluence Metric

Depriest, Kendall D.

ASTM Committee E10 on Nuclear Technology and Applications develops and maintains many standards that are relevant to the radiation metrology activities in Sandia National Laboratories' Radiation and Electrical Sciences Center. This is particularly true for the reactor facilities and Subcommittee E10.07 on Radiation Dosimetry for Radiation Effects on Materials and Devices. In the past decade, Subcommittee E10.07 has been making substantive changes to the standard widely used to assess radiation hardness to neutron effects in electronics, E722 – Standard Practice for Characterking Neutron Fluence Spectra in Terms of an Equivalent Monoenergetic Neutron Fluence for Radiation-Hardness Testing of Electronics. ASTM Standard E722 describes the method that defines the 1-MeV silicon and the 1-MeV gallium arsenide equivalent fluence radiation damage metrics. An evaluation of the impact of changes to the shape of the 1-MeV silicon equivalent fluence radiation damage metric from the 1985 version (E722-85) to the most recent version (E722-19) is performed.

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Mobile Device Application for Gunshot Trilateration

Booth, Stephanie B.; Carlson, Jeffrey J.

The New Mexico Small Business Assistance program at Sandia National Labs and Parental Values, LLC have agreed to explore commonly known principles to describe techniques in trilateration. The objective from Parental Values' standpoint is to use these commonly known principles for the purpose of their own software development by their employees. The software would be meant for mobile devices held by minors and the software would be monitored by parent(s) and/or guardians. The software would be able to notify parent(s)/guardian(s) in the event of an active shooter in a proximity close enough for the mobile devices' onboard microphones to detect a gunshot's noise. This document is meant for the employees of Parental Values to understand the commonly known principles as it applies to their intended implementation.

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Photoluminescence Spectroscopy to Determine Residual Stresses in Glass-to-Metal Seals

Huntley, Emily H.; Strong, Kevin T.; Elisberg, Brenton E.; Meserole, Stephen M.; Diebold, Thomas W.

In components with two materials, such as glass-to-metal (GtM) seals, residual stress can reduce long-term reliability. Therefore, it is important to be able to accurately measure residual stress within these components. The residual stress can be from a large strain due to the mismatch of thermo-physical response of the two materials or a small strain due to stress and/or structural relaxation. Both modeling and experimental measurements were conducted on multiple GtM seals constructed with CGI 930 glass with purposely added alumina particles. The alumina particles have an established Cr fluorescence pattern and the shift in position of these peaks can accurately measure the strain of the alumina crystals. Photoluminescence spectroscopy (PLS) technique was utilized due to its non-destructive nature and high spatial resolution. PLS scans of these components were analyzed and compared to the models developed previously.

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Geomechanical Characterization of Geo-architectured Rock Specimens Using Gypsum-based 3D Printing

Williams, Michelle W.

Due to natural heterogeneity in rock specimens, classifying rock characteristics can present difficulties. 3D printing geo-architectured rock specimens has the potential to reduce the heterogeneity and help evaluate characteristics with reproducible microstructures, bedding, and strength to advance mechanical interpretations. This testing focused on 3D printing effects on strength and rock behavior by varying amount of binder, printing direction, and atmospheric conditions. A powder-based Gypsum 3D printer was used to create 1.5-inch diameter cylindrical samples. Unconfined compressive strength (UCS) testing was completed on these samples to gather failure plots and peak strength. Multiple batches of cylindrical samples were printed with varying printing direction, binder amount, and atmospheric conditions. UCS results show that the strongest samples were those that were printed perpendicular to the loading direction compared to those printed parallel or 45 degrees. Due to reactions of the printing material with water, those at dry conditions were the strongest. Samples with the most binder amount proved to also be stronger than those with less. 3D printing of rock samples has to the potential to reduce heterogeneity rock presents, however additional factors introduced by the printing process can affect overall rock strength and behavior. Test results of the 3D printed geo-architected rock specimens demonstrated reasonable reproducibility and appear to be a promising path towards increasing the ability to characterize natural rock.

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Foresee the Future: Using Machine Learning, Climate, and Site Characteristics to Predict PV Solar Plant Generation

Gunda, Thushara; Cai, May

Accurately predicting power generation for PV sites is critical for prioritizing relevant operations & maintenance activities, thereby extending the lifetime of a system and increasing the amount of revenue generated. Machine learning techniques can help us in this regard by providing more accurate predictions of PV power production, such that the forecasts take into account not only a site's system design characteristics, but also important weather and climate information. This type of research is important because we can leverage the vast amounts of SCADA data we collect to build more effective, accurate models that can help improve our performance management.

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Magnetic Shielding with Soft Magnetic Alloys

Cummings, Jeremy C.

Abnormal electrical environments receive a lot of attention from nuclear safety engineers, but less attention has been paid to the magnetic effects that accompany such environments. Engineers with backgrounds outside of physics or electrical engineering may not be as familiar with this topic; this report serves as a brief summary of the phenomena and proposes experiments to support practical engineering solutions. Lightning strikes, in particular, create an environment hazardous to electronics, especially to components that rely on magnetic coupling for normal function. The most direct method of mitigating unwanted magnetic effects caused by lightning is to shield the component of interest; several materials and configuration options are explained here. An experimental approach is recommended to validate numerical modeling.

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Economic Impact Brochure (FY19)

Valencia, J L.

Sandia has demonstrated its commitment to the small business community through annually increasing small business goals, the 5% New Mexico small business pricing preference, and the newly launched Mentor-Protégé' program. We look forward to continuing to build relationships with small and diverse suppliers to achieve our national security mission and spur economic growth in New Mexico and across the country.

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Build Guide for the Geophysical Monitoring System (GMS) Common Source Code 2019 Release

Harris, James M.; DuBois, Justin D.; Rivera, Katherine Z.; Manzanares, David A.

This document provides a "Build Guide" for a Generic Runnable System (GRS) of the Geophysical Monitoring Systems (GMS) common source code. This guide includes a list of software dependencies and licenses, hardware specifications, and instructions for how to build the system from the source code. The document is written for individuals who are experienced as administrators of Linux systems.

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Inertial Fusion Energy program within OFES

Slutz, Stephen A.

Inertial Fusion is being supported by the NNSA for weapon physics and, although net gain has not yet been attained, significant progress has been made. National Ignition Facility (NIF) capsules have attained fusion gain within the fuel. MagLIF, which is presently being studied at the Z facility, has demonstrated the basic principles of Magneto-Inertial Fusion (MIF), which may provide an alternative path to fusion. Despite these successes there is presently no effort to determine if inertial fusion can be used to generate electrical energy. It would be prudent to have a small program directed to the application of inertial fusion for energy (IFE). This program would not have the same goals as the NNSA and should thus be funded by OFES.

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Development, Demonstration and Validation of Data-Driven Compact Diode Models for Circuit Simulation and Analysis

Aadithya, Karthik V.; Kuberry, Paul A.; Paskaleva, Biliana S.; Bochev, Pavel B.; Leeson, Kenneth M.; Mar, Alan M.; Mei, Ting M.; Keiter, Eric R.

Compact semiconductor device models are essential for efficiently designing and analyzing large circuits. However, traditional compact model development requires a large amount of manual effort and can span many years. Moreover, inclusion of new physics (e.g., radiation effects) into an existing model is not trivial and may require redevelopment from scratch. Machine Learning (ML) techniques have the potential to automate and significantly speed up the development of compact models. In addition, ML provides a range of modeling options that can be used to develop hierarchies of compact models tailored to specific circuit design stages. In this paper, we explore three such options: (1) table-based interpolation, (2) Generalized Moving Least-Squares, and (3) feedforward Deep Neural Networks, to develop compact models for a p-n junction diode. We evaluate the performance of these "data-driven" compact models by (1) comparing their voltage-current characteristics against laboratory data, and (2) building a bridge rectifier circuit using these devices, predicting the circuit's behavior using SPICE-like circuit simulations, and then comparing these predictions against laboratory measurements of the same circuit.

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Big Wheel Farm: Farmland Scour Reduction

Olson, Sterling S.; Chartrand, Chris C.; Roberts, Jesse D.

Flood irrigation benefits from low infrastructure costs and maintenance but the scour near the weirs can cause channeling of the flow preventing the water from evenly dispersing across the field. Using flow obstructions in front of the weir could reduce be a low cost solution to reduce the scour. The mitigation strategy was to virtually simulate the effects of various geometric changes to the morphology (e.g. holes and bumps) in front of the weir as a means to diffuse the high intensity flow coming from the gate. After running a parametric study for the dimensions of the shapes that included a Gaussian, semi-circle, and rectangle; a Gaussian-hole in front of the gates showed the most promise to reduce farm field shear-stresses with the added benefit of being easy to construct and implement in practice. Further the simulations showed that the closer the Gaussian-hole could be placed to the gate the sooner the high shear stress could be reduced. To realize the most benefit from this mitigation strategy, it was determined that the maximum depth of the Gaussian-hole should be 0.5 m. The width of the hole in the flow direction and the length of the Gaussian-hole normal to the flow should be 0.5 m and 3 m respectively as measured by the full width at half maximum.

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Transient and Steady-State Inverse Problems in Sierra/Aria

Wagman, Ellen B.; Kurzawski, Andrew K.; Bunting, Gregory B.; Walsh, Timothy W.; Aquino, Wilkins A.; Brunini, Victor B.

Inverse problems arise in a wide range of applications, whenever unknown model parameters cannot be measured directly. Instead, the unknown parameters are estimated using experimental data and forward simulations. Thermal inverse problems, such as material characterization problems, are often large-scale and transient. Therefore, they require intrusive adjoint-based gradient implementations in order to be solved efficiently. The capability to solve large-scale transient thermal inverse problems using an adjoint-based approach was recently implemented in SNL Sierra Mechanics, a massively parallel capable multiphysics code suite. This report outlines the theory, optimization formulation, and path taken to implement thermal inverse capabilities in Sierra within a unit test framework. The capability utilizes Sierra/Aria and Sierra/Fuego data structures, the Rapid Optimization Library, and an interface to the Sierra/InverseOpt library. The existing Sierra/Aria time integrator is leveraged to implement a time-dependent adjoint solver.

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Advanced WEC Dynamics and Controls MASK3 Test

Coe, Ryan G.; Bacelli, Giorgio B.; Spencer, Steven; Kjdulle, Dforbus

Sandia National Laboratories and the Department of Energy (DOE) have completed on a multi-year program to examine the effects of control theory on increasing power produced by resonant wave energy conversion (WEC) devices. The tank tests have been conducted at the Naval Surface Warfare Center Carderock Division (NSWCCD) Maneuvering and Sea Keeping Basin (MASK) in West Bethesda, MD. This report outlines the "MASK3" wave tank test within the Advanced WEC Dynamics and Controls (AWDC) project. This test represents the final test in the AWDC project. The focus of the MASK3 test was to consider coordinated 3-degree-of-freedom (3DOF) control of a WEC in a realistic ocean environment. A key aspect of this test was the inclusion of a "self-tunine mechanism which uses an optimization algorithm to update controller gains based on a changing sea state. The successful implementation of the self-tuning mechanism is the last crucial step required for such a controller to be implemented in real ocean environments.

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Results 17801–18000 of 96,771
Results 17801–18000 of 96,771