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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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At least 523 records · Page 29
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

IER-407 CED-3b Rev-1: Experiment Execution Report for the Inherently Safe Subcritical Assembly (ISSA) Subcritical Measurements

This set of benchmark subcritical multiplicity experiments was conducted at the ISSA experiment center of Lawrence Livermore National Laboratory. The purpose of these subcritical experiments, as described in the ISSA final design report, was to measure fission neutrons by collecting time-tagged data corresponding to a maximum multiplication of approximately 20. The fission source for this experiment was Materials Test Reactor (MTR)-type highly enriched uranium fuel assembly, which is composed of nineteen fuel plates. One, two, four, six and nine ISSA fuel assemblies were closely packed and loaded inside a support fixture assembly and immersed in water. Four 3 He proportional counters were placed around the fuel assemblies, and list-mode experimental data was taken. Additionally, efficiency calibration measurements with calibrated neutron sources were conducted. The LLNL developed codes BIGFIT and OSANTI RESTART will be used to evaluate the measured data and calculate the experimental multiplication.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2018

Methodology for Estimating Safe Charge Limits of Flammable Refrigerants in HVAC&R Applications - Part 1

Refrigerant flammability introduces new challenges to the usage of low global warming potential (Low GWP) refrigerants in real life applications. Those challenges are centered around the deflagration risk associated with their use and its implications on personal safety. Standards have been developed to systematically set maximum allowable flammable refrigerant charges to ensure safety in case of refrigerant leakage. These standards were initially based on limited testing and numerical analyses of refrigerant leakage into confined spaces.

42 ENGINEERING↗
DOE OSTI2018

CarbonSAFE Rocky Mountain Phase I: Ensuring Safe Subsurface Storage of Carbon Dioxide in the Intermountain West

An integrated CCS pre-feasibility study, CarbonSAF E Rocky Mountain Phase I, was conducted by the U niversity of Utah and its partners as part of the US D epartment of Energy’s Carbon Storage Assurance a nd Facility Enterprise (CarbonSAFE) program. The a ssembled project team consisted of academic, indus try and governmental agencies covering the technic al and non- technical challenges of a commercial-sc ale CO 2 storage facility capable of storing 50 million tonnes of anthropogenically-sourced CO 2 . The Rock y Mountain CarbonSAFE team identified the Hunter Power Plant in central Utah as the primary source of CO 2 on which this study would be focused. The nea rby Huntington power plant, also operated by Rocky Mountain Power, was evaluated as a secondary sou rce of CO 2 . The Hunter plant was chosen because o f an interest in CO 2 capture technology by the plant operator, Rocky Mountain Power, and also because i t is a representative example of a typical coal-fired g enerating station in the Rocky Mountain west. Amine -based and cryogenic-based capture assessments w ere performed for approximately 3 million tonnes per year for one of the boiler units at the Hunter plant, yi elding cost of capture estimates of $\$56$/tonne and $\$4 1.50$/tonne. Transportation and intermediate compre ssion would increase the per tonne costs, but will be highly dependent on specific injection locations and available rights-of-way. A high-level technical sub-ba sinal evaluation was performed on the area surround ing the Hunter and Huntington power plants to verify CO 2 storage capacity and integrity. Initial geologic c haracterization efforts focused on sites immediately adjacent to the Hunter plant, including the deep eolia n Permian White Rim Sandstone, which in outcrop a nd core from other locations indicates high permeabi lity and high porosity. However, petrophysical logs fr om wells near Hunter indicate porosity of only 2-4%. As a result, potential injection sites were moved stru cturally down-dip (to the west), into the high permea bility (~200 mD) and high porosity (20%) Navajo san dstone. A comprehensive analysis of the reservoir a nd seals was conducted, providing data to the model , simulation and risk assessment groups on the proje ct. CO 2 capacity estimates for the Navajo Sandston e approximately 18 kilometers from the Hunter plant are well in excess of the 50 million tonnes goal of the project. Area of Review Delineation and Risk Asse ssment on the Navajo, associated seals and shallow groundwater aquifers identified the most significant risks and mitigation options. A non-technical assessment to a commercial-scale CO 2 storage facility in central Utah was conducted. EPA Underground Injection Control Class VI and National Environmental Policy Act permitting present particularly challenging issues related to the development of any saline aquifer for CO 2 storage, including the area around the Hunter plant. While surface and subsurface ownership and ri ghts are not straightforward, especially on any privat e land, many of the stakeholders in central Utah are accustomed and open to oil/gas/mineral-related activities similar to what would be required for CO 2 storage sites.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2019

Transforming the Uranium Fuel Cycle: Safe & Economical Conversion of DUF 6 to DUF 4

The goal of this rapid response project was to show that DUF 6 can be converted to DUF 4 using hexamethyldisilane (HMDS), producing trimethylsilyl fluoride (TMS-F) as a by-product. These would represent a significant improvement in the safety and economy of the current DUF 6 to DUF 4 downconversion, which produces HF as a by-product.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2019

Arms Control Opportunities for Inherently Safe and Secure Nuclear Command, Control, and Communications

The Department of Defense Science Board has stated that the United States is "not prepared to defend againsr cyber-attacks and that the military could lose "trust in the information and ability to control U.S. systems and forces [including nuclear forces]." One potential weak spot in cyber-security is storing encryption keys in computer memory. This paper explores the use of hardware devices (so-called Physical Unclonable Functions, or PUFs) to generate, in the nuclear weapon itself, unique encryption keys each time they are needed. Not only do we find that this has the potential to mitigate a number of cyberthreats, but such hardware has the potential to greatly diminish the total uncertainty associated with radiation-based warhead authentication procedures; a procedure many analysts feel will be key to future arms control regimes. After outline the use of PUFs in nuclear command, control, and communications--and indicating some of the areas that still require further research--we discuss their application to arms control and warhead authentication

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2019

Transforming the Uranium Fuel Cycle: Safe & Economical Conversion of DUF 6 to DUF 4 [Slides]

Project Outcomes: Designed and fabricated SS reaction vessels for executing reactions with UF 6 at SIGMA, followed by transport and analysis at TA-48; Established a new capability at SIGMA for performing small mass transfers of UF 6 ; Safety documentation approved for performing new UF 6 chemistry at SIGMA; Staff training and conversion opportunity established for LANL Seaborg post-doc; Neat reaction with HMDS (CH 3 ) 3 Si-Si(CH 3 ) 3 produced fluorosilanes; In reactions with solvents, fluorination observed. No DUF 4 observed yet. Observations: Only 4 reactions were completed – more clearly needed; Due to problems with procurement, we did not get the mass control flow (MFC) unit until late August; Due to staff and time shortages UF 4 was never delivered from SIGMA to TA-48 by SHIP-IT; Established ability for future collaboration between C and Sigma.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2020

Working Safely at LANL during the COVID-19 Pandemic (Rev. 2)

The COVID-19 pandemic is an emerging, rapidly evolving public health emergency. The content of this course reflects the most up-to-date guidance and information from the Centers for Disease Control and Prevention (CDC), World Health Organization (WHO) and scientific literature available at the time the course was developed. Check the LANL COVID-19 Hub for the latest information and guidance. Updates to the course will be made as necessary to reflect evolving guidance form public health authorities and new data form the scientific literature.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2020

Aerial Crosspolarized NQR-NMR: Buried Explosive Detection From a Safe Distance

Nuclear quadrupole resonance is a non-destructive detection and inspection technique with potential as a non-destructive test (NDT) tool. Establishment of the capability opens the door to its use in furthering the mission of the labs. There are many possible uses of the capability: explosive detection and stress/strain detection in epoxies are two of the more obvious and are the main results of this work. Enhancement of the signal-to-noise ratio (SNR) and improvements in the acquisition time of the experiment were key focuses of this work. These were achieved by combing special spin-lock pulse sequences with cross-polarization (CP) schemes to improve the signals with shorter acquisition times. A novel rotating magnetic field device was created to facilitate CP in the field. Implementation of these schemes provided a significant reduction in SNR/time.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2020

Stabilization of Uranium Metal by Chloride Conversion-Economical, Safe, Scalable [Factsheet]

Researchers at Los Alamos National Laboratory have developed SUCCESS, a process to convert uranium metal to uranium tetrachloride enabling production of these valuable compounds for actinide science, molten salt nuclear reactors, and energy research. Conventional methods are problematic due to the oxide reduction processes use rare reagents and generate significant amounts of waste and hydride conversion process using chlorine at high temperature is hazardous. This new method using inexpensive reagents chemically transform uranium metal into uranium halide compounds under mild conditions. The facile conversion to stable uranium tetrachloride could reduce the need to mine uranium for uses other than nuclear, by recycling the uranium without oxidation. The Laboratory is interested in supporting further scale-up efforts using a Cooperative Research and Development Agreement (CRADA) or by granting a license to a qualified entity

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

Science-integrated Artificial-intelligence for Flooding and precipitation Extremes (SAFE)

A grand challenge in hydrologic science is to understand why signals of climate change and variability, which are often visible in precipitation extremes at aggregate scales, are not consistently observed in the case of extreme flooding. However, a solution to this challenge may prove elusive unless the water cycle is viewed in an integrative manner. Thus, for riverine flooding, while Hortonian (infiltration excess) runoff may have stronger correlation with precipitation extremes and hence perhaps to warming trends or climate oscillators, Dunne (saturation excess) runoff may have a more complex relationships with time series of precipitation and with evaporation and transpiration, but rain-on-snow and snowmelt events may depend on land-surface and atmospheric temperatures. Atmospheric rivers and tropical cyclones lead to precipitation or flooding and are impacted by climate. Flooding assessments need to consider long-term baselines, evolving risk factors, coupled natural-human systems, and novel adaptation such as nature-inspired design.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

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.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2022

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.

33 ADVANCED PROPULSION SYSTEMS↗