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National Technology & Engineering Solutions of Sandia, LLC Technical Assistance With Energy Cloud (Final CTAP Report)

Jungwirth, Jessica

Sandia provided technical assistance to Energy Cloud to support the assessment of Energy Cloud’s technology for air filtration of the SARS-CoV-2 virus. The Energy Cloud system was developed to filter the SARS-CoV-2 virus from commercial HVAC systems, ducts, and enclosed rooms without generating ozone. The project included a 3-week experimental series with aerosolized SARS-CoV-2 virus at the University of Southern California’s biosafety level 3 (BSL-3) laboratory. USC provided the facility as well as experimentally derived measurements and assessment of the Energy Cloud system efficacy for SARSCoV-2 filtration from air handling systems.

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TYPE Other Report YEAR 2021
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MELCOR Code Change History: Revision 18019 to 21402

Humphries, Larry L.; Beeny, Bradley A.; Haskin, Troy C.; Albright, Lucas I.; Gelbard, Fred M.

This document summarily provides brief descriptions of the MELCOR code enhancement made between code revision number 18019and 21440. Revision 18019 represents the previous official code release; therefore, the modeling features described within this document are provided to assist users that update to the newest official MELCOR code release, 21440. Along with the newly updated MELCOR Users’ Guide [2] and Reference Manual [3], users are aware and able to assess the new capabilities for their modeling and analysis applications.

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TYPE SAND Report YEAR 2021
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Computational and Experimental Validation of Fractal-Fin, Dimpled Solar Heat Collector

Rodriguez, Salvador B.

A 3 foot x 3 foot x 3 foot aluminum solar collector was manufactured using computer numerical control. The interior of the device included six triangular dimpled fins for enhanced heat transfer. The interior vertical wall on the south side was also dimpled. The solar collector working fluid was based on water, and the collector consisted solely of passive heat transfer mechanisms (no moving parts), making it ideal for off-the-grid and rural applications. Two types of heat transfer experiments were conducted. One experiment had external flat heaters attached on the top and the front side, while the other four sides were insulated. Except for the bottom surface, the second experiment had all its exterior surfaces sprayed with black solar paint to collect as much solar heat as possible. Temperature data as a function of time was collected using 14 thermocouples spread strategically throughout the solar collector. In addition, computational fluid dynamics (CFD) simulations were conducted using the dynamic Smagorinsky large eddy simulation turbulence model. The first simulation considered that both the top and front surfaces were exposed to a fixed temperature of 313.7 K (105 °F), while the remaining four surfaces were insulated. For the second simulation, all conditions were the same, except that the temperature for both heated surfaces was raised to 350 K (170.3 °F). The two temperatures are expected to bound the solar collector operational temperature during the late- Spring, Summer, and early-Fall months. The solar collector design, experimental data, CFD output, and a discussion of five manufacturing approaches and costs are documented in this report.

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TYPE SAND Report YEAR 2021
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Summary of Peace Engineering Biome Kickoff Workshop

Armenta, Mikaela L.; Hermina, Wahid L.; Hayden, Nancy K.; Passell, Howard; Garcia, Pablo; Jordan, Ramiro; Koechner, Donna; Amadei, Bernard

There are urgent calls to action by the NAE, the Nobel Prize Summit, the UN, and global scientists to address and solve, in this decade (2020 – 2030), crucial and widely recognized global challenges to peace and security before they become more complex and more environmentally, financially, and socially costly; before we reach the point of no return.

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TYPE Other Report YEAR 2021
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A Review of Local-to-Nonlocal Coupling Methods in Nonlocal Diffusion and Nonlocal Mechanics

Journal of Peridynamics and Nonlocal Modeling

D'Elia, Marta; Elia, Xingjie'; Seleson, Pablo D.; Tian, Xiaochuan; Yu, Yue

Local-to-nonlocal (LtN) coupling refers to a class of methods aimed at combining nonlocal and local modeling descriptions of a given system into a unified coupled representation. This allows to consolidate the accuracy of nonlocal models with the computational expediency of their local counterparts, while often simultaneously removing nonlocal modeling issues such as surface effects. The number and variety of proposed LtN coupling approaches have significantly grown in recent years, yet the field of LtN coupling continues to grow and still has open challenges. This review provides an overview of the state of the art of LtN coupling in the context of nonlocal diffusion and nonlocal mechanics, specifically peridynamics. Furthermore, we present a classification of LtN coupling methods and discuss common features and challenges. The goal of this review is not to provide a preferred way to address LtN coupling but to present a broad perspective of the field, which would serve as guidance for practitioners in the selection of appropriate LtN coupling methods based on the characteristics and needs of the problem under consideration.

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TYPE Journal Article YEAR 2021
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Report on High Energy Arcing Fault Experiments: Experimental Results from Low-Voltage Switchgear Enclosures

Lafleur, Chris; Taylor, Gabriel; Putorti Jr., Anthony D.; Salley, Mark H.

This report documents an experimental program designed to investigate High Energy Arcing Fault (HEAF) phenomena for low-voltage metal enclosed switchgear containing aluminum conductors. This report covers full-scale laboratory experiments using representative nuclear power plant (NPP) three-phase electrical equipment. Electrical, thermal, and pressure data were recorded for each experiment and documented in this report. This report covers experiments performed on two low-voltage switchgear units with each unit consisting of two vertical sections. The data collected supports characterization of the low-voltage HEAF hazard and these results will be used to support potential improvements in fire probabilistic risk assessment (PRA) methods. The experiments were performed at KEMA Labs located in Chalfont, Pennsylvania. The experimental design, setup, and execution were completed by staff from the NRC, the National Institute of Standards and Technology (NIST), Sandia National Laboratories (SNL) and KEMA. In addition, representatives from the Electric Power Research Institute (EPRI) observed some of the experimental setup and execution. The HEAF experiments were performed between August 26 and Augsut 29, 2019 on nearidentical Westinghouse Type DS low-voltage metal-enclosed indoor switchgear. The threephase arcing fault was initiated on the aluminum main bus or in select cases on the copper bus stabs near the breaker. These experiments used either nominal 480 volts AC or 600 volts AC. Durations of the experiments ranged from approximately 0.4 s to 8.3 s with fault currents ranging from approximately 9.2 kA to 19.3 kA. Real-time electrical operating conditions, including voltage, current and frequency, were measured during the experiments. Heat fluxes and incident energies were measured with plate thermometers, radiometers, and slug calorimeters at various locations around the electrical enclosures. Environmental measurements of breakdown, conductivity and electromagnetics were also taken. The experiments were documented with normal and high-speed videography, infrared imaging and photography. The results, while limited, indicated the difficulty in maintaining and sustaining low-voltage arcs on aluminum components of sufficient duration and at a single point as observed operating experience.

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TYPE Other Report YEAR 2021
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Results 10801–10850 of 101,000
Results 10801–10850 of 101,000
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