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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 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Short-lived noble gas effluent trends from a research reactor

An understanding of anthropogenic sources of radioactive noble gases in the atmosphere is needed to enhance the discrimination ability of the International Monitoring System's sensors. These sources include commercial and research nuclear reactors and medical isotope production facilities. While abiding by local environmental ordinances these facilities all emit noble gas radioisotopes through normal operation. Here, this research presents measurements and analysis of noble gas isotopes ( 41 Ar, 135 Xe, 135m Xe, 137 Xe, 138 Xe, 87 Kr, 88 Kr, and 89 Kr) made directly at the stack of the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory. The Xe and Kr noble gases are concurrently observed with 41 Ar, a neutron activation product, when the reactor is operational. The magnitude of the Xe and Kr noble gases released is not constant over the HFIR cycle, but they temporally match the 41 Ar trend. An isotope activity ratio analysis of these shorter lived isotopes combined with the observation of the cycle's temporal trend helps understand the noble gas production mechanism at the HFIR. Isotopes with short half-lives are not useful for long-range environmental monitoring. However, these measurements could potentially be combined with atmospheric modeling to predict the background source term of the longer-lived Xe ratios at a monitoring station.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2021

Materials and Fuels Complex Human Performance and Nuclear Safety Culture Pocket Guide

The facilities at the Materials and Fuels Complex (MFC) contain a diverse collection of nuclear research and development capabilities which enable experiments and engineering to drive the world’s nuclear energy future. It is our responsibility to ensure safe, efficient, and reliable operation of MFC facilities to support INL’s nuclear science and technology and national security missions. The MFC management plan makes it clear that safely achieving this takes the right people using good processes.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2020

Rapid Simulation of Irradiation Damage in PWR Internals (NSUF 2019 Milestone Report)

This document summarizes the progress made by Oak Ridge National Laboratory (ORNL) in collaboration with the University of Michigan on “Rapid Simulation of Irradiation Damage in PWR Internals,” a research project led by the University of Michigan and supported by US Department of Energy Office of Nuclear Energy Nuclear Science User Facilities Consolidated Innovative Nuclear Research program. In this reporting period, samples that were exposed to combined neutron and ion irradiation were prepared and shipped to the University of Michigan for further analysis. This report summarizes the specimen preparation performed at ORNL’s Low Activation Materials Development and Analysis facility. The benchmarking work of microstructural characterization on reactor-irradiated samples with different dose levels was completed.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Irradiation performance of a U-7Mo in Al-Si matrix dispersion full-size fuel plate assembly

The Korea Atomic Energy Research Institute (KAERI) is leading the Ki-Jang Research Reactor (KJRR) project with the intent to develop a new reactor for medical isotope production and other nuclear research purposes. The KJRR core is designed to use high density fuel system where uranium alloyed with 7 wt% molybdenum (U-7Mo) particles are dispersed in a matrix of aluminum alloyed with 5 wt% silicon (Al-5Si) and clad in aluminum alloy 6061 (Al-6061) to form fuel plates. KAERI developed a fabrication facility to construct KJRR fuel assemblies and partnered with the Idaho National Laboratory (INL) to irradiate a full-size fuel assembly, with 21 total fuel plates, in the Advanced Test Reactor (ATR). Irradiation testing and subsequent Post Irradiation Exam (PIE) campaigns were performed successfully over a multi-year project. Monte Carlo neutronic calculations, coupling with a depletion code, were performed based on ATR’s as-run power history which showed that the highest power plate (plate 20) reached 83.1 % end-of-life (EOL) local burnup based on initial 235 U content. Additionally, finite element thermal modeling was performed based as-run power history which showed a beginning-of-life (BOL) peak local heat flux of 184 W/cm 2 . No anomalous fuel performance was observed during the irradiation and target test conditions were achieved. PIE showed favorable performance of the fuel assembly regarding all important phenomena. This paper describes the KJRR fuel assembly irradiation conditions and PIE data to support the conclusion that it performed well, without evidence of unexpected or problematic fuel performance, within an irradiation test designed to bound the KJRR design environment.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2022

Does a visit to EBR-I improve perceptions of nuclear power?

The advancement of nuclear research depends not only on the improvements made by scientists and engineers, but also on public approval in the United States. Presently, the public is not just curious about new applications of nuclear power but also concerned about the potential impact on their own safety and environment. It is projected that nuclear power production in the U.S. will decline due to industry stagnation. The skepticism of nuclear energy has remained high for decades. These attitudes need to be understood by policymakers, industry, and advocates given the electricity needs, competition, and climate change. The Experimental Breeder Reactor-I is the world’s first nuclear reactor to produce usable electricity. It has been a museum since 1975 and sees an average of 10,000 visitors every summer. I set out to gauge the opinion of visitors as they tour the facility. In this research project, I conduct a public opinion poll (n=162) over the course of a week to see if a visit to EBR-I improves the perception of nuclear power. The results suggest that a visit to EBR-I increased perceptions of nuclear power in a positive direction.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2023

CRADA Number NFE-19-07859 with Purist, Inc. (CRADA Final Report)

Cooperative Research and Development Agreement (CRADA) NFE-19-07859 between Oak Ridge National Laboratory (ORNL) and Purist Inc. (Purist) focused on developing a technology for production of high purity radioisotopes using small-scale underutilized research nuclear reactors. Purist is developing a novel production mechanism that will produce, and efficiently isolate radioisotopes with high specific activity at small-scale research reactors. The goal of this technology is to enable underutilized smaller scale reactors, typically not capable of producing medical grade radioisotopes, to be utilized as a production supply source. Such radioisotope production facilities will complement production efforts of the few larger production facilities to reduce and prevent risk in the medical isotope supply chain. The work done under this CRADA explored target development, to maximize isotope production and separation using Purist’s technology to ultimately obtain a radioisotope product with high specific activity for use in medical applications. Furthermore, under this CRADA post production, capture, concentration and encapsulation of the radioisotope product was studied by developing post irradiation midi to microscale processes to capture, store and release the separated radioisotopes from large volumes of the capture matrix after production, via automated High-Pressure Ion Chromatography (HPIC) and microfluidic purification/separation systems. This will enable concentration of the radioisotope product obtained into small volumes, which will aid in packaging and transporting the final radioisotope product to users.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2023

Locating Operational Events of the Cooling Tower of a Nuclear Reactor with a Very Local Seismic Network

Geolocation of emergent seismic signals is challenging at close distances. Here, we used three-component data from a seismic network and a targeted experiment at a research nuclear reactor to locate seismic sources. Utilizing known events collected during the targeted experiment, we were able to infer source locations with seismic amplitudes and polarization characteristics of the data. Although the resolution of the source location is not perfect, the seismic amplitudes and polarization analysis offer useful constraints. For the known events, the source region inferred with our analysis includes the true source locations. Synthetic tests indicate the resolution is largely due to limited data coverage and measurement uncertainties because the synthetic tests show similar results compared with the field data. We identified the source of the unknown event through spectrum cross correlation between the signals from the known events and an unknown event. Our findings were confirmed by operational staff at the facility. When the propagation medium properties (i.e., seismic velocity and quality factor for attenuation) are known, our analysis can be applied to continuous data from a seismic array to infer both source amplitude and location. If the medium properties are not known, a targeted experiment can be conducted to estimate them.

58 GEOSCIENCES↗
DOE OSTI2025

High y + Shear-Stress Turbulence Implementation for High Flux Isotope Reactor Narrow Channel Flows

The research objective of this work was to improve the engineering predictions of the turbulence characteristics of flows in curved narrow channels. Such channel flows are commonly encountered in nuclear research and test reactors, with one of them being the high-flux isotope reactor (HFIR). Research reactors bear high heat fluxes, and the proper computing of turbulence is paramount for safe and reliable reactor operation. The study builds on the results of a previous direct numerical simulation of turbulence to inform a well-known Reynolds-averaged Navier–Stokes shear-stress turbulence model and improves its accuracy in simulating parallel channel flows. A new formulation of the loss term in the dissipation conservation equation is suggested. Combined with high wall distance computational grids, the new implementation provides a fast-running flow solution, suitable for engineering purposes. Model generalization for parallel channel flows, in a broader range of frictional Reynolds numbers, is suggested by introducing a new form of the model constants.

CFD↗
DOE OSTI2025

Advancing International Integration and Strengthening Responsible Peaceful Uses of Nuclear Applications Through Specialized Curriculums

Nuclear technology has been pivotal in addressing some of the most pressing global challenges, ranging from energy production to combatting infectious diseases to agricultural security. Oak Ridge National Laboratory (ORNL), as a leader in nuclear research and development including in the field of radioisotopes, is well situated to share lessons learned and enhance global collaboration from years of discoveries in the field. Accordingly, the U.S. Department of Energy’s National Nuclear Security Administration (NNSA) sponsors specialized educational programs at ORNL, with support from the IAEA, focused on advancing peaceful nuclear applications and associated industries while upholding strong nuclear safety, security, and safeguards standards. The Joint U.S./IAEA International School on Peaceful Uses of Nuclear Applications, launched in 2024, is a cornerstone of this collaboration. The school provides an opportunity for early-career professionals from around the globe to gain practical knowledge and skills in utilizing nuclear technologies for peaceful purposes. This initiative demonstrates the United States’ commitment to its obligations under the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), specifically Article IV, which calls on nuclear-weapon states to facilitate access to the peaceful uses of nuclear energy while guarding against the proliferation of nuclear weapons. In this paper, we explore the curriculum, objectives, and global impact of the program. Participants of the ICARST-2025 conference are invited to learn more about this program, contribute to its development, and explore opportunities for collaboration. This school exemplifies how strategic partnerships, and educational initiatives can drive the peaceful and beneficial use of nuclear technology worldwide

Raffo Caiado, Ana [ORNL] (ORCID:0009000239304805)↗
DOE OSTI2022

Environmentally Assisted Cracking Research for Current and Advanced Nuclear Structural Materials

Understanding environmentally assisted cracking is an important aspect of nuclear materials research, as it provides information about failure mechanisms that lead to safety concerns or shutdowns. Idaho National Laboratory has ongoing research to understand how materials behave in the harsh nuclear environments for both the current fleet of light water reactors, as well as advanced reactors, where materials are exposed to more extreme environments. Corrosion and cracking of current materials, advanced materials, and materials formed through advanced manufacturing techniques are being examined, with particular interest in irradiation effects on corrosion and cracking, as well as the effects of environmental impurities. Testing, such as stress corrosion cracking, corrosion fatigue, and in-situ crack growth measurements, as well as a suite of characterization tools, including electron microscopy techniques and x-ray computed tomography, are being utilized to better understand the material response, limitations, and cracking mechanisms to ensure safe and reliable nuclear plants.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Regressing Nuclear Reactor Power Level Using Low-Cost Sensor Network Data

Multisensor networks deployed at nuclear facilities can be leveraged to collect data used as inputs to machine learning models predicting nuclear safeguard relevant information. This work demonstrates an application of this idea by regressing nuclear reactor power levels, a key indicator for nuclear safeguard verification, at the McClellan Nuclear Research Center using data collected by five Merlyn multisensor platforms with LASSO and LSTM models. This work also demonstrates the use of Leave One Node Out to measure the importance of each multisensor for this regression problem providing insight into model explainability and allowing inferential hypotheses about the nuclear facility to be made. This work can be used as a starting point for future development of methods for regression on reactor power levels at nuclear facilities using multisensor network data.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2025

Passive Temperature Sensors for Nuclear Applications

In April 2007, the Department of Energy (DOE) designated the Advanced Test Reactor (ATR) a National Scientific User Facility (NSUF) to advance US leadership in nuclear science and technology. By attracting new users from universities, laboratories, and industry, this program supports basic and applied nuclear research to help address the nation's energy security needs. In support of this program, the Idaho National Laboratory (INL) established in-house capabilities to develop, fabricate, test, and qualify new and enhanced temperature sensors for irradiation testing. This effort is continuing today through the DOE?s Advanced Sensors and Instrumentation (ASI) program. Although most efforts emphasize sensors capable of providing real-time data, selected tasks have been completed to enhance passive sensors for irradiations where instrumentation leads cannot be included. These sensors include silicon carbide (SiC) monitors, melt wires and the sublime temperature monitor. SiC monitors are available to detect peak irradiation temperatures between 200°C and 800°C in reactor locations where instrumentation leads cannot be used. SiC monitors may be evaluated using specialized equipment installed at INL?s Measurement Sciences Laboratory (MSL). A melt wire inventory is also maintained at MSL. This inventory contains wires for specific use in irradiation experiments ranging in temperatures from 30°C to 1500°C. Melt wires and SiC monitors have had decades of research and application. Recent research has produced a passive monitor known as the sublime temperature monitor. This passive sensor has the capability of recording temperature gradients. This paper will discuss passive temperature sensors currently being researched and implemented under the ASI program.

11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

FY21 NNSA-IAEC Science Area V, Environmental ISR, Waste Management and Subsurface Science (Final Report)

The FY21 NNSA NA-22 Final Report represents the progress achieved over the past year (FY21) by the research team for Topic Area 3, Waste Management & Subsurface Science (WM3), and Topic Area 7, Radiation and Thermal Effects on Bituminous Rocks (WM7). WM3 and WM7 are part of Science Area V (Subsurface Science and Waste Management) in the NNSA-IAEC Science and Technology Working Group. The project was initiated four years ago (2017) with an MOU agreement between the U.S. National Nuclear Security Administration (NNSA) and the Israel Atomic Energy Commission (IAEC) to evaluate the feasibility of geological subsurface disposal of radioactive waste in Israel. The core WM3 and WM7 teams are comprised of scientists and engineers from Los Alamos National Laboratory, the Geologic Survey of Israel (GSI), and the Nuclear Research Center - Negev (NRCN), with a close collaboration to the teams from Sandia National Laboratory (SNL) and Lawrence Livermore Laboratory (LLNL)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2023

Large Detector Systems in Particle Physics Experiments & the Role Africa Will Play in Detector Technologies of the Future

In this talk, we will give a brief overview of some of the detector technologies deployed in large-scale experiments in particle physic research lab the world and through a specific Micro Pattern Gaseous Detector (MPGD) technologies example, we will discuss challenges associated to these technologies in term of production, assembly, characterization and deployment in complex detector system for the experiments. In the second half of the talk, we will initiate the discussion on the role that African countries could play in the development of detector technologies in the future for application in various field of fundamental and applied science. We will hope to engage the audience to explore initiatives under the African Strategy for Fundamental and Applied Physics (ASFAP) umbrella to encourage African research institutions and universities to invest in detector research and development (R&D) and in infrastructures dedicated aimed at covering all aspects of detector technologies and providing opportunities to generation of bright young African minds to take part in international collaboration of large-scale experiments at facilities such as the Electron Ion Collider (EIC) in the USA or the European Organization for Nuclear Research (CERN) and to contribute to the deployment and operation of detector technologies in future experiments.

Gnanvo, Kondo↗
DOE OSTI2023

Intern Poster Session

This poster has been developed for display during the 2023 Intern Poster Session. The poster is apart of the Nuclear Research and Experiments category. The focus of this poster is on the modifications made to the design of an integral effect test (IET) facility currently being designed for a new Small Modular Reactor (SMR) design. My contributions made to the IET facility are laid out along with an explanation on some of the aspects of designing a new nuclear reactor. This poster covers the ideas and importance of scaling and IET facilities with the context of the standards set by the NRC. There are also graphics of some other examples of IET facilities developed for other reactor designs. My contributions include designing the piping and instrumentation layout of the IET facility using CAD software. This is a key step in the process of designing this IET facility and needs to be designed to avoid excessive head loss.

42 ENGINEERING↗
DOE OSTI2020

Disposition of Newly Generated Transuranic Waste at ORNL - 20107

ORNL operates the High Flux Isotope Reactor, which provides a high neutron source for production of isotopes for medical, industrial, and nuclear research programs and is the US DoE's center for production, storage, and distribution for TRU isotopes (plutonium through californium). Operation of these facilities results in the generation of CH-TRU and RH-TRU waste for disposal at the WIPP. This paper describes the program ORNL is implementing in collaboration with the Carlsbad Field Office National TRU Program Difficult Waste Team to disposition newly generated TRU waste. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2025

Estimating Potential Tritium and Plutonium Production in North Korea’s Experimental Light Water Reactor

Our work explores North Korea's 100 MW-th Experimental Light Water Reactor (ELWR) and its potential contributions to the country's nuclear weapons program. Built at the Yongbyon Nuclear Research Center, the ELWR began operations in October 2023 and represents North Korea's first attempts at a light-water reactor using domestically-enriched, ceramic fuel. Our study examines possible configurations for energy, tritium, and tritium-plutonium co-production. Assuming a single-batch core, the ELWR can be used to annually produce 48-82 grams of tritium, which can supply 2-4 new boosted warheads each year, up to a maximum arsenal of 88-150 warheads total. Concurrent production of tritium and weapon-grade plutonium is also possible but requires reprocessing of spent ceramic fuel. Furthermore, these findings underscore how North Korea's nuclear capabilities may be advanced through the ELWR's dual-use potential.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2025

Verification and Validation of Open-Source Computational Fluid Dynamics Capabilities in MOOSE

The Multiphysics Object Oriented Simulation Environment (MOOSE) advances predictive modeling in nuclear research by simplifying the application design process and making modeling more efficient and accessible to researchers and the broader community. Because of MOOSE’s critical role in the scientific computation field, verification and validation are important to evaluate the reliability and credibility of MOOSE’s code, simulations, and models. To assess MOOSE’s Navier Stokes module and turbulence models, the following verification and validation University of Manchester ERCOFTAC cases were simulated in MOOSE, and the results were compared: Case 032 Turbulent Flow in a 2D Channel Case 079 Natural Convection in an Enclosed Cavity

46 - INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AN↗