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Spotlight SAR Data Collection Geometry from ECEF Coordinates

Doerry, Armin W.; Bickel, Douglas L.

High-performance spotlight Synthetic Aperture Radar (SAR) requires measurement of the radars motion during the synthetic aperture. A convenient coordinate frame for motion measurement is often not the convenient coordinate frame for motion compensation during the SAR data generation and image formation processing. A convenient frame for radar motion measurement is the Earth-Centered Earth-Fixed (ECEF) coordinate frame, whereas spotlight SAR processing typically require s polar coordinates from a selected Scene Reference Point (SRP). This report presents the conversion from ECEF coordinates to appropriate parameters for SAR processing.

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TYPE SAND Report YEAR 2020
DOIOSTI

The Rise in the Utilization of IoT Devices in Nuclear Facilities

Runyan-Beebe, Christopher A.

The term Internet of Things (loT) encompasses everything connected to the internet, but it is increasingly being used to define objects that "talk" to each other. A broader term is that loT are the devices that connect to each other and to the internet. It has been mentioned that loT offers the potential for a "Forth industrial revolution" (1). This is primally because of the ease of use and quick link-up of devices within an area. This poses options for great interactivity but also create security concerns as many of these devices may not have been vetted for industrial use. By allowing for the intercommunication of these devices and combining with automated systems, we can now gather information, provide analysis and create automotive actions. This allows for faster response times as well as lowering the overall cost for operations in nuclear power facilities. (2)

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TYPE Other Report YEAR 2020
DOIOSTI

Microgrid Design Toolkit (MDT) Simple Use Case Example for Islanded Mode Optimization (Software v1.3)

Eddy, John P.; Gilletly, Samuel D.; Bandlow, Alisa

This simple Microgrid Design Toolkit (MDT) use case will provide you an example of a basic microgrid design. It will introduce basic principles of using the MDT islanded mode optimization by modifying a baseline microgrid design and performing an analysis of the results. Please reference the MDT User Guide (SAND2020-4550) for detailed instructions on how to use the tool.

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TYPE SAND Report YEAR 2020
DOIOSTI

Microgrid Design Toolkit (MDT) Simple Use Case Example for the Microgrid Sizing Capability (Software v1.3)

Arguello, Bryan; Bandlow, Alisa; Ellison, James

This simple Microgrid Design Toolkit (MDT) use case will provide you an example of performing microgrid sizing by identifying the types and quantities of technology to be purchased for use in a microgrid. It will introduce basic principles of using the MDT microgrid sizing capability by comparing the results of two microgrids in two different markets. Please reference the MDT User Guide (SAND2020-4550) for detailed instructions on how to use the tool.

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TYPE SAND Report YEAR 2020
DOIOSTI

Effect of Line-Tower Coupling on E1 Pulse Excitation of an Electrical Transmission Line

2020 IEEE International Symposium on Electromagnetic Compatibility and Signal/Power Integrity, EMCSI 2020

San Martin, Luis; Warne, Larry K.; Campione, Salvatore; Halligan, Matthew; Guttromson, Ross

In a transmission line, we evaluate the coupling between a line and a tower above ground when the excitation is an El high-altitude electromagnetic pulse (HEMP). Our model focuses on capturing correctly the effect of the coupling on the peak of the HEMP induced current that propagates along the line. This assessment is necessary to accurately estimate the effect of the excitation on the systems and components of the power grid. This analysis is a step towards a quantitative evaluation of HEMP excitation on the power grid.

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TYPE Conference Poster YEAR 2020
DOIOSTIScopus

SIGNAL Game Manual

Lakkaraju, Kiran; Epifanovskaya, Laura W.E.; Letchford, Joshua; Whetzel, Jonathan H.; Armenta, Mikaela L.; Goldblum, Bethany; Tibbetts, Jake

SIGNAL is a first of its kind experimental wargame developed as part of the Project on Nuclear Gaming (PoNG). In this document we describe the rules and game mechanics associated with the online version of SIGNAL created by team members from the University of California, Berkeley, Sandia National Laboratories, and Lawrence Livermore National Laboratory and sponsored by the Carnegie Corporation of New York. The game was developed as part of a larger research project to develop the experimental wargaming methodology and explore its use on a model scenario: the impact of various military capabilities on conflict escalation dynamics. We discuss the results of this research in a forthcoming paper that will include this manual as an appendix. It is our hope that this manual will both contribute to our players' understanding of the game prior to play and that it will allow for replication of the SIGNAL game environment for future research purposes. The manual begins by introducing the terminology used throughout the document. It then outlines the technical requirements required to run SIGNAL. The following section provides a description of the map, resources, infrastructure, tokens, and action cards used in the game environment. The manual then describes the user interface including the chat functions, trade mechanism, currency and population counts necessary for players to plan their actions. It then turns to the sequence of player actions in the game describing the signaling, action, and upkeep phases that comprise each round of play. It then outlines the use of diplomacy including alliances with minor states and trade between players. The manual also describes the process for scoring the game and determining the winner. The manual concludes with tips for players to remember as they embark upon playing the game.

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TYPE SAND Report YEAR 2020
DOIOSTI

Computational fluid dynamics analysis of char conversion in Sandia's pressurized entrained flow reactor

Review of Scientific Instruments

Bosenhofer, Markus; Hecht, Ethan S.; Shaddix, Christopher R.; Konig, Bernhard; Rieger, Johannes; Harasek, Michael

Design and analysis of practical reactors utilizing solid feedstocks rely on reaction rate parameters that are typically generated in lab-scale reactors. Evaluation of the reaction rate information often relies on assumptions of uniform temperature, velocity, and species distributions in the reactor, in lieu of detailed measurements that provide local information. This assumption might be a source of substantial error, since reactor designs can impose significant inhomogeneities, leading to data misinterpretation. Spatially resolved reactor simulations help understand the key processes within the reactor and support the identification of severe variations of temperature, velocity, and species distributions. In this work, Sandia's pressurized entrained flow reactor is modeled to identify inhomogeneities in the reaction zone. Tracer particles are tracked through the reactor to estimate the residence times and burnout ratio of introduced coal char particles in gasifying environments. The results reveal a complex mixing environment for the cool gas and particles entering the reactor along the centerline and the main high-speed hot gas reactor flow. Furthermore, the computational fluid dynamics (CFD) results show that flow asymmetries are introduced through the use of a horizontal gas pre-heating section that connects to the vertical reactor tube. Computed particle temperatures and residence times in the reactor differ substantially from the idealized plug flow conditions typically evoked in interpreting experimental measurements. Furthermore, experimental measurements and CFD analysis of heat flow through porous refractory insulation suggest that for the investigated conditions (1350 °C, <20 atm), the thermal conductivity of the insulation does not increase substantially with increasing pressure.

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TYPE Journal Article YEAR 2020
DOIOSTIScopus

Sandia Nuclear Cartridge Concept

Mohagheghi, Amir H.; Middleton, Bobby D.

Nuclear power offers the promise of long-term electrical power for remote areas. Recent advances in passive safety and long-life cores make a reactor that can be operated autonomously for 20 years or more a real possibility. This white paper discusses a reactor concept that offers the potential for further development, resulting in a permanently hermetically-sealed "nuclear cartridge." The term "nuclear cartridge" is meant to imply a nuclear energy source that can be inserted into a site and operated autonomously until its energy has been depleted, then withdrawn and replaced by another cartridge. The concept can be scaled for various sizes, ranging from about 1 megawatt-electric (MWe) to about 100 MWe. The paper also discusses the concept of Integrated Safety, Operations, Security, and Safeguards (ISOSS) by design as it applies to this reactor design. Finally, a discussion of smart grids and how they can benefit the transfer of power to the end user is included. The Nuclear Cartridge concept has been developed with the following characteristics in mind: highly reliable autonomous operation coupled with international monitoring, requiring minimal on-site operations personnel; walkaway passively safe design; cartridge replacement cycle on the order of 20 years; load following capability; physical security by design requiring minimal security personnel during operations; and proliferation resistance by design. As illustrated in figure 1, integrating the reactor with advanced power conversion, smart grids, and other sources of energy results in a resilient and sustainable energy source.

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TYPE Other Report YEAR 2020
DOIOSTI

Metal Alloy and RHEA Additive Manufacturing for Nuclear Energy and Aerospace Applications

Rodriguez, Salvador B.

An open-literature search was conducted to consider the current status of the additive manufacturing (AM) industry with respect to metal alloys and refractory high entropy alloys (RHEAs). Key areas of interest include methodologies and applications that are suitable for the nuclear and aerospace industries, as well as other industrial applications. We investigated various promising 3D metal technologies, with emphasis on cost, operation, throughput, maintenance, and output volume size. In addition, technical issues and the current status of the metal printing market are summarized. The project scope also included the manufacturing of open-literature RHEA test coupons at Sandia's laser engineered net shape (LENS) machine.

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TYPE SAND Report YEAR 2020
DOIOSTI

High-Frequency Metal-Oxide Varistor Modeling Response to Early-time Electromagnetic Pulses

2020 IEEE International Symposium on Electromagnetic Compatibility and Signal/Power Integrity, EMCSI 2020

Bowman, Tyler C.; Halligan, Matthew; Llanes, Rodrigo

The electric power grid is one of the most critical infrastructures in the modern world, and the continued protection and resilience of this system from threats is of significant concern. One such set of threats is nanosecond-scale transient effects generated by high-altitude electromagnetic pulses, for which the effect on the power grid is still being studied. Lightning surge arresters serve as the current grid protection against fast transients but are designed and modeled for protection against lightning and switching transients. Surge arrester response to faster transients is not well known. This work defines a scalable metal-oxide surge arrester model with specific consideration to frequencies attributed to fast transient overvoltages from electromagnetic pulses. Measurements using vector network analyzer sweeps at low and high bias as well as high-voltage I-V curve traces are presented to define arrester behavior and to parameterize it from measurement data. The proposed model is compared to the standard IEEE model for lightning arresters in this paper. Furthermore, model parameters are defined by scalable terms to be easily implemented for transmission-level devices. The scalable model enables enhanced assessment of protection levels and grid susceptibility against fast transients.

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TYPE Conference Poster YEAR 2020
DOIOSTIScopus
Results 16601–16700 of 99,299
Results 16601–16700 of 99,299