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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 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

The Aerosol Model Benchmarking Repository: A toolkit for model intercomparison

The Aerosol Model Benchmarking Repository and Standards (AMBRS) project was initiated to provide tools and to establish community standards for benchmarking aerosol models. This report describes a set of open-source tools for building, running, and analyzing aerosol box model simulations in a standardized framework. The framework consists of three core components: AMBuilder, a CMake-based build system that compiles supported models consistently; AMBRS, a Python module that defines unified numerical experiments and executes them with aligned inputs; and PyParticle, an aerosol analysis package that standardizes output, computes diagnostics, and visualizes simulation results. Together, these tools enable reproducible intercomparison of aerosol schemes and support process-level evaluation of how model simplifications affect predictions of size distributions, cloud condensation nuclei activity, and other relevant properties relevant for the Earth-Energy system. Beyond its role in benchmarking, AMBRS provides a platform for studying aerosol processes across scales and can be used to generate training data for AI/ML applications in support of a broader hierarchical aerosol modeling strategy.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Data and code repository for "How do the weather regimes drive wind speed and power production at the sub-seasonal to seasonal timescales over the CONUS?"

There has been an increasing need for forecasting power generation at the sub-seasonal to seasonal (S2S) timescales to support the operation, management, and planning of the wind-energy system. At the S2S timescales, atmospheric variability is largely related to recurrent and persistent weather patterns, referred to as weather regimes (WRs). In the study "How do the weather regimes drive wind speed and power production at the sub-seasonal to seasonal timescales over the CONUS?", we identify four WRs that influence wind resources over North America using a self-organizing map (SOM) algorithm. These WRs are responsible for large-scale wind and power production anomalies over the CONUS at the S2S timescales. The WR-based reconstruction explains up to 50% of the monthly variance of power production over the western United States, and the explanatory power generally increases with the increase of timescales. The identified relationship between WRs and power production reveals the potential and limitations of the regional WR-based wind resource assessment over different regions of the CONUS across multiple timescales. This repository includes all the data and codes we use for analyses in this study. Users may use them to reproduce the results of this study on their end.

17 WIND ENERGY↗
DOE OSTI2023

Geomechanical in situ testing of fault reactivation in argillite repositories

Abstract. Pressurization of natural faults as a result of repository-induced effects can lead to their reactivation and permeability generation in case such features are present near disposal tunnels. Potential driving forces for such pressurization are the temperature increase caused by heat-producing high-level radioactive waste and the generation of hydrogen and other gases due to corrosion of engineered materials. We are primarily concerned about pressurization and fault activation in host rocks and faults that have very low natural permeability for pore pressure increases to dissipate, such as the argillite rocks currently investigated in Switzerland, France and other countries. This presentation discusses a series of in situ experiments of fault activation by fluid injection conducted in the argillite rock (Opalinus clay) at the Mont Terri underground research laboratory in Switzerland. A multi-model monitoring test bed was installed at Mont Terri that includes distributed fiber optics for strain, temperature, and acoustics; local fault pore pressure and three-dimensional displacement sensors; active seismic imaging; and passive seismic monitoring. The fault experiments (and their subsequent analysis via hydromechanical modeling) provide a new fundamental understanding of the coupling between pore pressure, fault deformation and permeability generation as a function of time and allow exploring how seismic and aseismic events may impact the integrity of faulted argillite host rock. Our experimental observations demonstrate that significant flow (and transport) can occur along the initially impermeable argillite fault when rupture is activated. However, the fault permeability decreases to almost its pre-activation value when fluid injection ceases and fluid pressure drops. Dilatant slip on the fault plane alone does not explain the observed increase in fault permeability; pressure-induced fault opening also plays a role, favored by the softness of the shale along with the fact that the structure of the fault zone prevents fluids from diffusing into the adjacent damage zone. Rupture initiation and permeability generation is initially aseismic, associated only with an increase in noise level and emerging tremors. Micro-earthquakes are initiated later in the experiments and typically occur away from the fluid-pressurized area. Hydromechanical models show that stress transferred from the initial aseismic deformation can build up to stress criticality and later induce seismic rupture. After presenting the experimental results, we will close the presentation with an outlook to future experimental campaigns using the fault test bed at Mont Terri. We are currently planning a controlled thermal stimulation of the fault, where instead of fluid injection as a trigger mechanism we will heat up the nearby rock volume and measure potential effects on fault stability. Lessons learned from our past and future experiments will help inform the safety assessment of geologic disposal in argillite host rock.

Birkholzer, Jens T.↗
DOE OSTI2026

QPatLib: A community repository of measurement-based quantum computing patterns

QPatLib is a community repository of measurement‑based quantum computing (MBQC) patterns and associated metadata, intended to support reuse, benchmarking, and reproducible comparison of MBQC constructions across platforms and compilers. Patterns in QPatLib are expressed in a standardized, human‑readable measurement calculus representation. Details can be found here: https://doi.org/10.48550/arXiv.2605.12502

graph states↗
DOE OSTI2019

Dose to Cementitious Material for Moderator Exclusion in a Spent Nuclear Fuel Canister During a Repository Timeframe

One of the concerns regarding direct disposal of spent nuclear fuel (SNF) dual-purpose canisters (DPCs) currently in dry storage is criticality during disposal time frames (e.g., 10,000 years or more). Preconditioning DPCs with appropriate filler materials (e.g., cementitious materials, low-melting metals) before disposal could prevent post-closure criticality by means of moderator displacement. However, potential radiolysis of the filler material by ionizing radiation and release of reactive chemical species over repository time frames may negatively impact the mechanical and chemical properties of the filler materials. Evaluation of the energy deposited in candidate filler materials by SNF radiation is essential for the calculation of radiolytic species. This paper provides an evaluation of the total energy deposited by gamma and neutron radiation in a candidate filler material over 10,000 years for a representative pressurized water reactor SNF DPC. The canister is assumed to contain identical SNF assemblies with a burnup value of 55 GWd/MTU, which is the bounding burnup value for more than 95% of the SNF inventory discharged from 1968 to 2013. The evaluated energy deposited per unit volume of filler material between 10 years and 10,000 years after fuel discharge is approximately 9.3E+23 eV/cm3. Gas production from radiolysis was not evaluated and may be revisited in future work. Radiolysis may be the principal gas generation mechanism for a cementitious system.

Radulescu, Georgeta↗
DOE OSTI2019

Getting Data Out of the Ground: Modern Data Challenges Facing EGS Collab, the DOE Geothermal Data Repository, and the Geothermal Industry

The amount of data being generated by the geothermal industry is increasing exponentially. Advanced tools, higher resolution sensors, and digitally integrated equipment are providing valuable insight into geothermal exploration and operational efficiencies, but the volumes of data they generate and the unique properties of Enhanced Geothermal System (EGS) projects are creating challenges of their own. This paper explores those challenges and the steps the U.S. Department of Energy (DOE) is taking to address them through comprehensive data management strategies, improvements to DOE's Geothermal Data Repository (GDR), and the development of a secure data collaboration tool for DOE's Frontier Observatory for Research in Geothermal Energy (FORGE) and EGS Collab projects.

15 GEOTHERMAL ENERGY↗
DOE OSTI2022

Pathways to a Sustainable Aviation Ecosystem: Flight DNA: An Anonymized Aviation Data Tool and Repository

The National Renewable Energy Laboratory (NREL) has deep experience developing secure, national data repositories, which it augments with analysis, technology and market expertise, high-performance computing, and innovative data visualization. By adapting the architecture of existing mobility databases (i.e., Fleet DNA, the Transportation Secure Data Center, the National Fuel Cell Technology Evaluation Center), NREL can build a powerful aviation data clearinghouse - Flight DNA - that helps stakeholders navigate the web of pitfalls and possibilities generated by new aviation technologies.

aviation↗
DOE OSTI2023

Improving the Quality of Geothermal Data Through Data Standards and Pipelines Within the Geothermal Data Repository: Preprint

For machine learning outputs to be applicable to real world problems, high quality data are needed to ensure high quality results. With the more recent emphasis on machine learning in geothermal, there is an increasing need for greater focus on the quality of the data available for use in these projects. For example, Geothermal Operational Optimization Using Machine Learning (GOOML) utilized large quantities of geothermal power plant operational data to inform power plant operational configurations to maximize power generation. High quality datasets result from dependable sensors or devices collecting data, high frequency of measurements, sufficient data points, adequate metadata, reliable storage of data, and sufficient data curation. Another component that contributes to high quality data is reusability, which can be enhanced through data standardization. Data Standardization creates consistency in formatting and contents of like datasets, lessening preprocessing requirements and ensuring adequate information provided by a given dataset. The Geothermal Data Repository (GDR) aims to help improve data quality through automated data standardization for high-value datasets through the implementation of data pipelines alongside reliable and accessible long-term storage for datasets. As such, the GDR has decided to shift away from recommending the use of Excel-based content models and towards the implementation of automated data pipelines. This takes the burden of data standardization off the user and project team and will increase the availability of standardized geothermal data available through the GDR. A set of recommendations, or a data standard for each data type will exist with each data pipeline in order to advise data collection for maximum usability for future research. This paper serves to describe the GDR's proposed transition towards data standardization through automated data pipelines, to discuss the need for and value of such a shift, and to call for suggestions from the community regarding the most useful data standards and pipelines.

data↗
DOE OSTI2013

Cigeo, the French Geological Repository Project - 13022

The Cigeo industrial-scale geological disposal centre is designed for the disposal of the most highly-radioactive French waste. It will be built in an argillite formation of the Callovo-Oxfordian dating back 160 million years. The Cigeo project is located near the Bure village in the Paris Basin. The argillite formation was studied since 1974, and from the Meuse/Haute-Marne underground research laboratory since end of 1999. Most of the waste to be disposed of in the Cigeo repository comes from nuclear power plants and from reprocessing of their spent fuel. (authors)

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DOE OSTI2013

Wireless Transmission of Monitoring Data out of an Underground Repository: Results of Field Demonstrations Performed at the HADES Underground Laboratory - 13589

As part of the European 7. framework project MoDeRn, Nuclear Research and Consultancy Group (NRG) performed experiments in order to demonstrate the feasibility of wireless data transmission through the subsurface over large distances by low frequency magnetic fields in the framework of the geological disposal of radioactive waste. The main objective of NRG's contribution is to characterize and optimize the energy use of this technique within the specific context of post-closure monitoring of a repository. For that, measurements have been performed in the HADES Underground Research Laboratory (URL) located at Mol, Belgium, at 225 m depth. The experimental set-up utilizes a loop antenna for the transmitter that has been matched to the existing infrastructure of the HADES. Between 2010 and 2012 NRG carried out several experiments at the HADES URL in order to test the technical set-up and to characterize the propagation behavior of the geological medium and the local background noise pattern. Transmission channels have been identified and data transmission has been demonstrated at several frequencies, with data rates up to 10 bit/s and bit error rates <1%. A mathematical model description that includes the most relevant characteristics of the transmitter, transmission path, and receiver has been developed and applied to analyze possible options to optimize the set-up. With respect to the energy-efficiency, results so far have shown that data transmission over larger distances through the subsurface is a feasible option. To support the conclusions on the energy need per bit of transmitted data, additional experiments are foreseen. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Modeling of Coupled Thermo-Hydro-Mechanical-Chemical Processes for High-Level Radioactive Waste Repositories - 17361

To ensure that multi-barrier systems in high-level radioactive waste (HLW) repositories can efficiently perform their functions and isolate the waste from the biosphere, coupled thermo-hydro-mechanical-chemical (THMC) processes used for the performance assessment of HLW disposal facilities should be modeled. To evaluate coupled THMC processes, the DECOVALEX project, a unique international research collaboration project initiated in 1992, developed mathematical models and field experiments involving THMC processes in engineered barrier systems and host rocks for HLW disposal. The DECOVALEX project and the current status of coupled THMC model development can provide further insights into the performance assessment of HLW disposal facilities. This study provides information regarding the DECOVALEX project and reviews the development of coupled THMC models. The study results furnish knowledge of coupled THMC processes and techniques for the performance assessment and safety analysis of the final HLW disposal. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Problems Related to Temperature-Induced Processes in Long-Term Repositories for Nuclear Waste - 17514

Concepts for the final disposal of high level radioactive waste in deep geological formations must consider the heat pulse produced from radioactive decay during operations and in the post-closure phase as an important factor for the integrity of barrier systems. Several safety cases in different countries limit the maximum temperature at the boundary between the technical barrier/canister surface to the host rock/buffer material to 100 C. Increases in maximum temperature have very diverse effects with respect to the type, intensity and range of the heat pulse. These depend, among other factors, on i) the amount of heat emitted, ii) the type of host rock including site-specific characteristics, iii) the safety and repository concept and further site-specific boundary conditions. The German Commission on the Disposal of High-level Radioactive Waste (Commission) recommended, for precautionary reasons, that the temperature limit at the outer surface of waste containers should not exceed 100 C. Higher temperatures could only be considered if the maximum physically possible temperatures in the respective host rock have been reliably set as a result of research findings. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Risks of Hazardous Substances in Radioactive Waste for the Konrad Repository in Germany - 17522

When disposing of radioactive waste with negligible heat generation, the activity of the radionuclides is limited. However, the waste including radioactive material comprises a certain proportion of non-radioactive material. The risk of hazardous contamination of the groundwater by non-radioactive substances must be taken into account. It must be ascertained that the non-radioactive material cannot affect near-surface groundwater, which is a resource for drinking water supply. To achieve this, limit values on the amount of hazardous substances in the total waste volume shall be determined. In 2002 a regulatory approval was granted to the 'Konrad' final storage facility for radioactive waste with negligible heat generation according to the German Water Resources Act. This approval is embedded in the license (plan-approval decision) based on the German Atomic Energy Act. The approval is based on the model of a possible discharge of contaminants from the final storage facility. In a long-term simulation spanning 300,000 years, contact of the waste with the groundwater in the surrounding rock formations over the postoperational phase was conservatively assumed. The maximum amount of allowable disposal of substances - such that no concern of affecting the near-surface groundwater arises - can be derived from the solubility of the respective substances. Implementing the permit according to the Water Resources Act requires: - classification of the waste through delivery declaration obligations - monitoring the substance inspection in the waste to assess its suitability for the disposal, and - stock keeping procedures for the disposal waste by the operator. While the repository is operated by the Federal Office for Radiation Protection (BfS) (http://www.bfs.de./EN/home/home{sub n}ode;), reporting to the Federal Environment Ministry, the statutory water permit is issued and applied by the State of Lower Saxony as responsible state authority. A waste package/container list supplements a comprehensive list of substances. From this - depending on the respectively conditioned waste - material vectors can be derived. For this purpose, BfS provides a database with a substances and container list to the waste owners. In the meantime, first experiences have been collected in applying the approval. More than 540 waste containers with a total mass of almost 6,000 Mg have been controlled and are ready for disposal. In our presentation we will show the recent development in supervising the preparation for the disposal of mixed waste. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Planning large-scale excavation and construction activities within an aerially constrained site for construction of a repository for low and short-lived intermediate level radioactive waste at the Bulgarian national disposal facility - 15372

The Bulgarian State Enterprise for Radioactive Waste Management (SERAW) is planning the construction of a near-surface repository for low and short-lived intermediate level radioactive waste, the National Disposal Facility (NDF), at the Radiana Site adjacent to the Kozloduy Nuclear Power Plant (KNPP). The Site, a rectangular area approximately 1.2 km east-west by 0.4 north-south, is located on a slopping area between the second and sixth loess terraces above the River Danube with elevations ranging from approximately +40 m to elevation +95 m. Construction of the NDF will be divided into three phases separated by approximately 20 years each. The first phase will see the construction of the primary support facilities, referred to as the Auxiliary Buildings and including the Waste Reception and Buffer Storage (WRBS) Building, and the first set of 22 reinforced concrete disposal cells and supporting infrastructure, including a network of subsurface observation galleries, the Infiltration Network Control (ICN) Galleries. Each disposal cell will be 20.15 m long by 17.05 m wide by 9.45 m in height. The disposal cells will be arranged in two parallel rows. Disposal activities will be conducted using overhead cranes installed inside of track mounted mobile roofs. Each row of disposal cells will be serviced by one mobile roof. The mobile roofs will be supported by massive concrete foundations. Construction at the site will present several logistical challenges that will need to be overcome to fully realize the NDF. First in order to begin construction of these facilities nearly 1 million 3 of soil will require excavation and handling. Consistent with requirements to minimize potential environmental impacts identified in the site Environmental Safety Assessment (EIA) excavated soil will, to the extent possible, remain onsite. Approximately three quarters of the soil can be accommodated within the site boundaries. Another challenge results from requirements imposed by the ground conditions. The sub-grade at the site, which consists primarily of loess, will require considerable improvement. To this end a 5 m thick loess-cement cushion will be constructed across much of the site. Specifically, the cushion will be required beneath the disposal cells and the WRBS Building. Construction of the loess-cement cushion in the disposal area will require detailed planning and coordination, particularly as the cushion beneath the disposal cells also contains embedded structures, including the ICN Galleries as well as massive concrete foundation beams required for the two mobile roofs. Construction of these structures will require planned interruptions in the construction of the loess-cement cushion. Specific cement types and strict quality requirements will be required for completion of the loess-cement cushion as well as for completion of the ICN Galleries. The construction planning will need to account for the large volumes of soil to be excavated as well as ensuring sufficient material supplies in terms of both quality as well as quantity. Large quantities of materials including both dry cement for mixing with the loess, and wet concrete for pouring of the mobile roof foundations are accounted for by the plan. However, even after completion of these activities additional challenges are addressed by the plan related to the contemporaneous construction management of the auxiliary buildings and the disposal cells. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Corrosion Kinetics of Stainless Steel by Hydrogen Measurement under Deep Geological Repository Condition - 16047

Spent fuel assemblies consisting of stainless steels are expected to be disposed of in a deep underground repository. The radionuclides release and gas generation from activated metallic wastes in a disposal system will be controlled by the corrosion reaction. Most studies on stainless steel corrosion have been investigated under corrosion rates around several μm.a{sup -1}. A recent study has revealed that the corrosion rate of stainless steel is extremely slow-less than nm.a{sup -1} at 303 K. In the present study, corrosion kinetics at different temperatures up to 353 K were evaluated from the oxidation reaction by hydrogen gas measurement using 18Cr-8Ni austenitic stainless steel in a deoxygenated glass ampoule filled with a dilute NaOH solution of pH 12.5 for 24 months. Uniform corrosion and a reaction of 3Fe + 4H{sub 2}O → Fe{sub 3}O{sub 4} + 4H{sub 2} were assumed. After 24 months, the corrosion rates, which decreased with time but increased with rising temperature, were on average 7.80 x 10{sup -4}, 2.65 x 10{sup -3}, and 7.62 x 10{sup -3} μm.a{sup -1} at 303 K, 323 K, and 353 K, respectively. The corrosion kinetics were found to follow a parabolic rate law, which suggests the corrosion process is under diffusion control. The activation energy evaluated by the Arrhenius relationship of the parabolic rate constants has been determined to be 82.5 ± 6.2 kJ/mol, which corresponds to the values at high temperatures down to 423 K. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

A New Manufacturing Method of Bentonite Pellets as a Gap Filling Material for HLW Repository - 16110

In high-level waste (HLW) repositories in Japan, there is a need to properly deal with gaps that surround buffers made of bentonite-based material, which are inevitably generated during construction. Bentonite pellets are thought to be a candidate material for filling these gaps. To fill the gaps densely in order to ensure desired buffer quality, high-density pellets with spherical shape would be suitable, and we have developed a new method for manufacturing such bentonite pellets, which is different from conventional methods. The new method first produces spherical pellets by extrusion and spheronization by alternately using two commercially available pelletizing machines. Then, the pellets, which do not have a very high density because of their water content, are turned into high-density ones using dry shrinkage. For typical Japanese sodium bentonite, we confirmed that spherical pellets can be manufactured when the water content is relatively high within the range of 25 to 30%. We observed that proper dry shrinkage enables the wet spherical pellets with a low density of about 1,500 kg/m{sup 3} to turn into ones with a high dry density of about 2,000 kg/m{sup 3} . Drying slowly causes the proper dry shrinkage. We performed simple laboratory tests to evaluate the filling performance of pellets produced by the new manufacturing method. The maximum filling density obtained was 1,540 kg/m{sup 3} when large (20-mm diameter) and small (1-mm diameter) pellets were mixed in the proportion of 60 % to 40 %, which is considerably higher than the previously reported maximum filling density in Japan, which was about 1,300 kg/m{sup 3}. (authors)

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