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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Ensuring a Nuclear Power Plant Safe State Following an EMP Event - Task 7 Deliverable: EMP Testing of Secondary Coupling to Instrumentation Cables
Sandia National Laboratories performed tests to address the potential vulnerability concerns of a coupled High-Altitude Electromagnetic Pulse (HEMP) inducing secondary coupling onto critical instrumentation and control cables in a nuclear power plant, with specific focus on early-time HEMP. Three types of receiving cables in nine configurations were tested to determine transfer functions between two electrically separated cables referenced to the common mode input current on the transmitting cable. One type of transfer function related the input short circuit current and resulting open circuit voltage on the receiving cable. The other transfer function related the input short circuit current and the resulting short circuit current on the receiving cable. A 500 A standard HEMP waveform was input into the transfer functions to calculate peak coupling values on the receiving cables. The highest level of coupling using the standard waveform occurred when cables were in direct contact, with a peak short circuit current of 85 A and open circuit voltage of 9.8 kV, while configurations with separated cables predicted coupling levels of less than 5 A or 500 V.
Sandia National Labs Scaled Wind Farm Technology (SWiFT) Facility - Navigating Safely into the 2020s.
Abstract not provided.
The Automated Mobility District Implementation Catalog, 2nd Edition: Safe and Efficient Automated Vehicle Fleet Operations for Public Mobility
This second volume of the Automated Mobility District (AMD) Implementation Catalog series has been prepared in three parts to assist readers in their review and understanding of the technical information herein. The material may be more easily ingested if each of the three parts is read and then contemplated for its ramifications to the specific interest of the reader before continuing to the next part. Further, each part has been prepared with the intent that it could be read independently from the others. Part 1 is Progress of Automated Vehicle R&D for Deployments in Passenger Service; Part 2 is 10 Early Deployment Sites as Prototypes of AMD Implementation; Part 3 is Five Cardinal Principles for AMD Implementation.
EIC Machine Protection System: safe operation of Rapid Cycling Synchrotron with updated parameters
This note considers safety of operation of the EIC Rapid Cycling Synchrotron (RCS) with updated RCS parameters. This note is concerned only with a potential damage of in-vacuum components due to a direct beam deposit. The problem of the heating produced by the synchrotron radiation of the electron beam is not the topic of this note.
ARC-SAFE: Accelerated Response Semiconducting Contactors and Surge Attenuation for DC Electrical Systems: 1.5-2 kV/3-10 A Circuit Breaker Demonstration.
Abstract not provided.
Molten Salt-Based Batteries for Safe, Reliable, Long-Duration Energy Storage.
Abstract not provided.
ARC-SAFE: Accelerated Response Semiconducting Contactors and Surge Attenuation for DC Electrical Systems, FY23 Annual Meeting Posters.
Abstract not provided.
Industrial Ergonomics And Safe Lifting Practices: Food Depot [Slides]
Injuries happen when we go beyond what tissues can handle. It's repeated loading and subsequent failure of soft tissue that seem to account for most low back pain. This presentation discusses some common causes of workplace injuries and ways to reduce the likelihood of them happening.
Safely Exploring Solar: A Guide for Austin Energy Customers
It's easy to get overwhelmed as you start to explore your solar options. There is a wealth of information available out there, particularly online, and it can be hard to know who to trust. This informational guide has been adapted from Austin Energy's Solar Education Course and other national best practice resources, as of May 1, 2023. It will help you understand some of the key concepts and resources available to help you on your solar journey if you have a home in Austin Energy's service territory and are considering installing solar. This document includes: (1) Austin Energy Programs and Services Related to Solar; (2) Tips for Spotting a Solar Scam; (3) Things to Know When Designing Your System; (4) Key Considerations When Shopping for a Solar Contractor; and (5) Final Takeaways.
Additives in Localized High Concentration Electrolytes for Safe Lithium-Ion Batteries
In this work, the effects of various additives in a localized high concentration electrolyte (LHCE) on the cycling performance of lithium (Li)-ion batteries were studied. The LHCEs utilize trimethyl phosphate as a flame-retarding solvent and 1H,1H,5H-octafluoropentyl 1,1,2,2-tetrafluoroethyl ether as a medium-high flash point diluent, for the purpose to reduce the electrolyte flammability and improve the battery safety, which are not possessed by the conventional electrolytes of LiPF 6 in organic carbonates due to their high flammability. The LHCEs have unique solvation structure which enables the use of flame-retardant solvents to greatly decrease the electrolyte flammability as well as enhance the battery cycling stability. However, the additives added in the LHCEs result in different battery performances. The organic carbonate additives largely reduce the initial capacities although the cell capacity can be partially recovered with cycling. The two phosphate salt additives behave better than the organic carbonate additives in terms of cell capacity and cycling stability. More cell performance evaluation will be conducted and the detailed characterization will be performed to investigate the root causes of different behaviors of additives in the LHCEs on battery performances.
KOMPASS-II: Compaction of Crushed salt for Safe Containment – Phase 2
Long-term stable sealing elements are a basic component in the safety concept for a possible repository for heat-emitting radioactive waste in rock salt. The sealing elements will be part of the closure concept for drifts and shafts. They will be made from a welldefinied crushed salt in employ a specific manufacturing process. The use of crushed salt as geotechnical barrier as required by the German Site Selection Act from 2017 /STA 17/ represents a paradigm change in the safety function of crushed salt, since this material was formerly only considered as stabilizing backfill for the host rock. The demonstration of the long-term stability and impermeability of crushed salt is crucial for its use as a geotechnical barrier. The KOMPASS-II project, is a follow-up of the KOMPASS-I project and continues the work with focus on improving the understanding of the thermal-hydraulic-mechanical (THM) coupled processes in crushed salt compaction with the objective to enhance the scientific competence for using crushed salt for the long-term isolation of high-level nuclear waste within rock salt repositories. The project strives for an adequate characterization of the compaction process and the essential influencing parameters, as well as a robust and reliable long-term prognosis using validated constitutive models. For this purpose, experimental studies on long-term compaction tests are combined with microstructural investigations and numerical modeling. The long-term compaction tests in this project focused on the effect of mean stress, deviatoric stress and temperature on the compaction behavior of crushed salt. A laboratory benchmark was performed identifying a variability in compaction behavior. Microstructural investigations were executed with the objective to characterize the influence of pre-compaction procedure, humidity content and grain size/grain size distribution on the overall compaction process of crushed salt with respect to the deformation mechanisms. The created database was used for benchmark calculations aiming for improvement and optimization of a large number of constitutive models available for crushed salt. The models were calibrated, and the improvement process was made visible applying the virtual demonstrator.
How Safe Are Solid-State Batteries? An Exploration of Heat Release
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ARC-SAFE: Accelerated Response Semiconducting Contactors and Surge Attenuation for DC Electrical Systems
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ARC-SAFE: Accelerated Response semiconducting Contactors and Surge Attenuation For DC Electrical systems (Final Scientific/Technical Report)
The landscape of power transmission and distribution is quickly evolving as more power conversion is done through power electronics and transmitted or distributed at medium voltage direct current (MVDC). As power electronics tend to store less energy and be less resilient to faults than conventional power transformers, a reliable and fast protection against faults is critical to protect power electronics (PE) based infrastructure, especially for medium- and high-voltage applications. This motivates the development of PE based protection circuits to replace slower contemporary electromechanical breakers. In this project a novel PE based MVDC circuit breaker is developed; the new design is comprised of 1) a normally-on leg made of commercially-available, cascaded SiC junction field effect transistors (JFETs) with a passive balancing network, and 2) a normally-off leg based on an optically-triggered gallium nitride (GaN) photoconductive semiconductor switch (PCSS). The normally-off leg was designed to be quickly turned on, to divert current to an auxiliary dissipative circuit, as the normally-on leg is turned off. This approach, using solid-state devices, was selected for a high-performance, fast-switching operation for the DC circuit breaker as compared to approaches that use slower mechanical switches. To be practical, the circuit breaker must have low conduction loss (low Ron) in the normally-on leg and fast coordinated triggering of the normally-off leg to avoid damage from inductive flyback, which could be considerable for long lengths of cable.