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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 91 records · Page 5

Neutrino signatures of 100 2D Axisymmetric Core-Collapse Supernova Simulations

ABSTRACT We present in this paper a public data release of an unprecedentedly large set of core-collapse supernova (CCSN) neutrino emission models, comprising 100 detailed 2D axisymmetric radiation-hydrodynamic simulations evolved out to as late as ∼5 s post-bounce and spanning an extensive range of massive-star progenitors. The motivation for this paper is to provide a physically and numerically uniform benchmark data set to the broader neutrino detection community to help it characterize and optimize subsurface facilities for what is likely to be a once-in-a-lifetime galactic supernova burst event. With this release, we hope to (1) help the international experiment and modelling communities more efficiently optimize the retrieval of physical information about the next galactic CCSN, (2) facilitate the better understanding of core-collapse theory and modelling among interested experimentalists, and (3) help further integrate the broader supernova neutrino community.

Astronomy & Astrophysics↗

Addressing Market Issues in Electrical Power Systems with Large Shares of Variable Renewable Energy

This paper reports recent findings from IEA Wind TCP Task 25, which compiles international experiences and research related to large-scale integration of wind and other renewable energy. In the paper, we address the main challenges for market integration of variable renewable energy, relating to price formation, cost recovery, balancing and other grid services. The paper gives an overview of recent scenario studies on electricity price impacts of (1) various generation, energy storage and demand types in different markets, and (2) different market designs and energy/climate policies. Studying markets with very high shares of variable renewable energy requires an improved set of analysis tools for forecasting market outcomes, estimating flexibility needs and sources, and assessing resource adequacy. Key market features need to be investigated within these improved analytical capabilities for systems transitioning to high shares of variable renewable energy, storage and flexible demand. System services that can be supported by markets will likely need to be revisited. Finally, this paper identifies open questions and suggested future market design work for supporting systems with very high shares of variable renewable energy, which are to be addressed in follow-up work of Task 25 collaborative research.

cost recovery↗

Distributed Solar Quality and Safety in India: Key Challenges and Potential Solutions

The quality and safety of solar systems and their installation has become a concern for investors, regulators, consumers, and Discoms in India. The push for low prices and lack of quality standards are driving project developers to install low quality products, with poor system design and execution on-site. Existing literature and stakeholder interviews point to the rampant use of low quality, sub-standard solar products in India. These products deliver less energy than expected, or have high detrition rates, or have lower product life–all of which are serious issues for developers whose return on investment depend on the amount of power generation from these solar systems for the expected life of the project. Equipment which does not conform to the minimum quality standards also creates safety risks for the distribution network. Performance and safety concerns lower investor and consumer confidence in solar products with the potential to threaten market development. This report formulates a set of recommendations to concerned authorities in India to improve the quality and safety of rooftop solar systems. Primary and secondary sources are employed to understand the current solar quality and safety scenario in India to provide the basis for future recommendations. An overview of international experiences and lessons learned on solar quality and safety issues is also conducted to understand potential solutions for India.

24 POWER TRANSMISSION AND DISTRIBUTION↗

LBNF/DUNE Cryostats and Cryogenics Infrastructure for the DUNE Far Detector (Design Report)

DUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on both a near detector and a cryogenic far detector. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines many tens-of-kilotons of fiducial mass with sub-centimeter spatial resolution to collect neutrino events and image them with high precision. Given its size, this detector will be implemented as a set of up to four modules, each of which will require its own cryostat that will contain approximately 17.5 metric kilotons of ultra-pure liquid argon (LAr). The cryogenics infrastructure to support the detector modules includes systems to receive, transfer, store, purify, and maintain the LAr. This design report describes the cryostats and the cryogenics infrastructure required for the first two detector modules; this infrastructure is designed to support expansion to up to four far detector modules.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE 10658 Project Sensitivity-Driven Wide Area Protection (SWAP) Coordination Tools for IBRs

Utilities have seen a rapid increase in solar, wind, and battery energy storage systems that interconnect to their electric system through inverters. Inverter-Based Resources (IBRs) have fault current characteristics that are unlike the fault current response of traditional rotating-machine-based generators, which is well-known and repeatable. IBR’s non-traditional fault current behavior is due to the IBR control scheme, which is configured to provide a clean AC output but also protects the inverter’s sensitive power electronics devices from damage from conditions such as overcurrent. This results in a low fault current magnitude, low or no negative sequence current injection, the variability of sequence component currents, the variability of voltage with respect to current angles, and the lack of inertia. The control scheme also results in a fault current response that can vary between manufacturers and between models of the same manufacturer. High penetration of IBRs can adversely affect the protection schemes applied in areas with high penetration of IBRs. With the proliferation of IBRs, utilities are finding out that conventional protection schemes are not adequately equipped to protect the electric systems. This is mainly because the existing protection elements and practices have been designed based on the fault current response of conventional rotating machines. In several cases, the available literature does not provide any clear solution for the issues when the protection scheme does not operate properly near IBRs. This report identifies various protection challenges due to IBRs that industry is facing, from the utility perspective. Instead of focusing on one issue, this report looks broadly at all the challenges that system protection has experienced with high penetration of IBRs. Based on the IBR response from various utilities during real fault events and gathering perspectives from different utility SMEs via questionnaire, the report summarizes the gathered data and internal experiences.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Utilities Perspective on Protection Challenges with High IBR Penetration

Utilities have seen rapid increase in Solar, Wind, and Battery Energy Storage Resources that interconnect to their electric system through Inverters. Inverter-Based Resources (IBRs) have fault current characteristics that are unlike the fault current response of traditional rotating-machine-based generators, which is well known and repeatable. IBR’s non-traditional fault current behavior is due to the IBR control scheme, which is configured to provide a clean AC output but also protect the inverter’s sensitive power electronics devices from damage, one source of which is overcurrent. This results in low fault current magnitude, low or no negative sequence current injection, the variability of sequence component currents, the variability of voltage with respect to current angles, and the lack of inertia. The control scheme also results in a fault current response that can vary between manufactures and between models of the same manufacturer. High penetration of IBRs can adversely affect the protection schemes applied in areas with high penetration of IBRs. With the proliferation of IBRs, utilities are finding out that conventional protection schemes are not adequately equipped to protect the electric systems. This is mainly because the existing protection elements and practices have been designed based on the fault current response of conventional rotating machines. In several cases, the available literature does not provide any clear solution for the issues when the protection scheme does not operate properly near IBRs. This presentation identifies various protection challenges due to IBRs that industry is facing, from the utility perspective. Instead of facing on one issue, we are looking broadly on all the challenges that system protection has experienced with high penetration of IBRs. Based on the IBR response from various utilities during real fault events and gathering perspective from different utility SMEs via questionnaire, the presentation summarizes on gathered data and internal experiences.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Utility Perspective on Protection Challenges with High Penetration of IBRs

Utilities have seen rapid increase in Solar, Wind, and Battery Energy Storage Resources that interconnect to their electric system through Inverters. Inverter-Based Resources (IBRs) have fault current characteristics that are unlike the fault current response of traditional rotating-machine-based generators, which is well known and repeatable. IBR’s non-traditional fault current behavior is due to the IBR control scheme, which is configured to provide a clean AC output but also protect the inverter’s sensitive power electronics devices from damage, one source of which is overcurrent. This results in low fault current magnitude, low or no negative sequence current injection, the variability of sequence component currents, the variability of voltage with respect to current angles, and the lack of inertia. The control scheme also results in a fault current response that can vary between manufactures and between models of the same manufacturer. High penetration of IBRs can adversely affect the protection schemes applied in areas with high penetration of IBRs. With the proliferation of IBRs, utilities are finding out that conventional protection schemes are not adequately equipped to protect the electric systems. This is mainly because the existing protection elements and practices have been designed based on the fault current response of conventional rotating machines. In several cases, the available literature does not provide any clear solution for the issues when the protection scheme does not operate properly near IBRs. This report / presentation identifies various protection challenges due to IBRs that industry is facing, from the utility perspective. Instead of facing on one issue, this report looks broadly on all the challenges that system protection has experienced with high penetration of IBRs. Based on the IBR response from various utilities during real fault events and gathering perspective from different utility SMEs via questionnaire, the report summarizes on gathered data and internal experiences.

14 SOLAR ENERGY↗

Simulation Center for Runaway Electron Avoidance and Mitigation (SCREAM SciDAC) (Technical Final Report)

Runaway electrons can severely damage the plasma facing components on ITER during a major disruption and pose a major risk for tokamak fusion. It has been recognized that an adequate disruption mitigation system (DMS) is essential for the safe operation of ITER. The United States is responsible for the design and implementation of the disruption mitigation system on ITER, and in July 2016 the Simulation Center for Runaway Electron Avoidance and Mitigation (SCREAM) was launched by DOE, in a joint Fusion Energy Sciences (FES) and Advanced Scientific Computing Research (ASCR) collaboration. SCREAM was a comprehensive theory and simulation SciDAC center that provided physics guidance in the avoidance and mitigation of runaway electrons, and in tandem with domestic and international experiments, helped establish the qualitative and quantitative bases for safe operational scenarios and viable mitigation techniques. The SCREAM center assembled a national team of experts in runaway electron physics, tokamak disruptions, magnetohydrodynamic (MHD) simulation, and advanced algorithms and computing. The team combined advanced simulation and analysis capability facilitated by direct participation of ASCR SciDAC institutes with theoretical models and code development by FES scientists to focus on the runaway risk for ITER and tokamaks in general. The research scope was focussed on integrated simulations of kinetic runaway electrons, including MHD and fluid models of impurity transport, within a research plan guided by theory. The specific research tasks were (1) establish the fundamental physics of runaway generation, saturation, and dynamical evolution in a tokamak; (2) examine the critical path toward runaway avoidance; and (3) investigate the viability and effectiveness of the leading candidate schemes for runaway mitigation. In all three areas, members of the team carried out scoping studies that established the readiness for rapid and critical advances, especially in the deployment and further development of large-to extreme-scale simulation tools. Our multi-pronged computational approach included (1) relativistic Fokker-Planck solvers with discretization in phase space, (2) self-consistent particle-in-cell techniques, (3) particle-based Monte-Carlo, and (4) MHD-particle hybrid simulations. Cross-check between these different methods provided an additional means for verification and further bolstered the fidelity of our physics prediction. Validation against experimental results brings confidence to the predictive capability for ITER and frequently leads to new ideas for understanding and mitigating the thermal quench driven runaway electron phenomenon.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Lessons Learned from Site Selection Efforts for Deep Geological Disposal

This report discusses international experiences from site selection of deep geological repositories (DGR) for radioactive waste disposal. Based on experiences from three countries with recent or ongoing site selections, the report describes different site selection approaches and summarizes lessons learned. The German and Swiss programs are two slightly different examples of one end of the spectrum of potential siting approaches: Starting with the entire country, a technically based downselection is performed to select the repository site. The Canadian program is an example of the other end of the spectrum: Here, the program started with an extensive engagement program with Canadians to collaboratively develop a socially acceptable and technically sound national approach for the long-term management of used nuclear fuel. This was followed by the launch of a collaboratively developed consent-based siting process designed to seek an informed and willing host with suitable sites, considering both technical and community well-being site requirements.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Analytical study of the optimum geometric configuration of a space shuttle materials laboratory

A steady state, collisionless flow analysis was made of the density distribution within a hemisphere-disc system due to independent, uniformly distributed internal gas sources. The model was used to estimate the density within a molecular shield, deployed from the shuttle orbiter, which contained internal experiments having a prescribed gas source. Contour plots of the density distribution within the system were presented for disc-to-hemisphere radius ratios of .1, .3, .5, .7, and for disc-to-hemisphere surface emission flux density ratios of .01, 1, 100. The hemisphere-disc system was compared to the empty hemisphere, and it was found that if the disc emission flux density was the same as the hemisphere and the disc radius was not greater than 1/3 of the hemisphere radius, the increase in density at the center of the hemisphere-disc system was less than 50%.

Clay, F. P., Jr.↗

The depiction of Alboran Sea Gyre during Donde Va? using remote sensing and conventional data

Experienced oceanographic investigators have come to realize that remote sensing techniques are most successful when applied as part of programs of integrated measurements aimed at solving specific oceanographic problems. A good example of such integration occurred during the multi-platform international experiment, Donde Va? in the Alboran Sea during the period June through October, 1982. The objective of Donde Va? was to derive the interrelationship of the Atlantic waters entering the Mediterranean Sea and the Alboran Sea Gyre. The experimental plan conceived solely with this objective in mind consisted of a variety of remote sensing and conventional platforms: three ships, three aircraft, five current moorings, two satellites and a specialized beach radar (CODAR). Integrated analyses of these multiple-data sets are still being conducted. However, the initial results show detailed structure of the incoming Atlantic jet and Alboran Sea Gyre that would not have been possible by conventional means.

Laviolette, P. E.↗

Proceedings of the Fifth Parabolic Dish Solar Thermal Power Program

The proceedings of the Fifth Parabolic Dish Solar Thermal Power Program Annual Review are presented. The results of activities within the Parabolic Dish Technology and Module/Systems Development element of the Department of Energy's Solar Thermal Energy Systems Program were emphasized. Among the topics discussed were: overall Project and Program aspects, Stirling and Brayton module development, concentrator and engine/receiver development along with associated hardware and test results; distributed systems operating experience; international parabolic dish development activities; and non-DOE-sponsored domestic dish activities. Solar electric generation was also addressed.

Lucas, J. W.↗

Space Station - The next logical step

NASA is committed to the development of a permanently manned Space Station within a decade, in concert with European and Japanese space agencies. In addition to continuing scientific research, the Space Station will proceed with applied science and industrialization experiments. International cooperation opportunities arise within the Space Station program for users (in the definition of missions), for builders (in the development of station resources and capabilities), and operators (in the orbital maintenance of the Space Station).

Finn, T. T.↗

Moderate Resolution Imaging Spectrometer (MODIS) design evolution and associated development and verification of data product efforts

The Moderate Resolution Imaging Spectrometer (MODIS) is a key observing facility to be flown on the Earth Observing System (EOS). The facility is composed of two instruments called MODIS-N (nadir) and MODIS-T (tilt). The MODIS-N is being built under contract to NASA by the Santa Barbara Research Center. The MODIS-T is being fabricated by the Engineering Directorate at the Goddard Space Flight Center. The MODIS Science Team has defined nearly 40 biogeophysical data products for studies of the ocean and land surface and properties of the atmosphere including clouds that can be expected to be produced from the MODIS instruments shortly after the launch of EOS. The ocean, land, atmosphere, and calibration groups of the MODIS Science Team are now proceeding to plan and implement the operations and facilities involving the analysis of data from existing spaceborne, airborne, and in-situ sensors required to develop and validate the algorithms that will produce the geophysical data products. These algorithm development and validation efforts will be accomplished wherever possible within the context of existing or planned national and international experiments or programs such as those in the World Climate Research Program.

Salomonson, Vincent V.↗

Regional studies of the land surface using space-based means

Regional ecological studies are considered in the context of the global change problem. The Kursk-91 international experiment is used to illustrate applications of remote sensing data and data bases of field experiments for assessment of parameters of the state of the soil and vegetative cover and subsequent study of biospheric stability on the basis of regular satellite observations.

Kozoderov, V. V.↗

The Future of New Discoveries on the International Space Station

The Materials Science program is one of the five Microgravity research disciplines in NASA's Human Exploration and Development of Space (HEDS). This research uses the low gravity environment to obtain the fundamental understanding of various phenomena effects and it's relationship to structure, processing, and properties of materials. The International Space Station (ISS) will complete the first major assembly phase within the next year thus providing the opportunity for on-orbit research and scientific utilization in early 2001. Research will become routine as the final Space Station configuration is completed. Accommodations will support a variety of Materials Science payload hardware both in the US and international partner modules. This paper addresses the current scope of the flight investigator program that will utilize the various capabilities on ISS. The type of research and classification of materials that are addressed using multiple types of flight apparatus will be explained. The various flight and ground facilities that are used to support the NASA program are described. The early utilization schedule for the materials science payloads with associated hardware will be covered. The Materials Science Research Facility and related international experiment modules serves as the foundation for this capability. The potential applications and technologies obtained from the Materials Science program are described.

Schlagheck, Ronald↗

A New Direction for NASA Materials Science Research Using the International Space Station

NASA recently created a fifth Strategic Enterprise, the Office of Biological and Physical Research (OBPR), to bring together physics, chemistry, biology, and engineering to foster interdisciplinary research. The Materials Science Program is one of five Microgravity Research disciplines within this new enterprise's Division of Physical Sciences Research. The Materials Science Program will participate within this new enterprise structure in order to facilitate effective use of ISS facilities, target scientific and technology questions and transfer scientific and technology results for Earth benefits. The Materials Science research will use a low gravity environment for flight and ground-based research in crystallization, fundamental processing, properties characterization, and biomaterials in order to obtain fundamental understanding of various phenomena effects and relationships to the structures, processing, and properties of materials. Completion of the International Space Station's (ISS) first major assembly, during the past year, provides new opportunities for on-orbit research and scientific utilization. Accommodations will support a variety of Materials Science payload hardware both in the US and international partner modules with emphasis on early use of Express Rack and Glovebox facilities. This paper addresses the current scope of the flight investigator program. These investigators will use the various capabilities of the ISS to achieve their research objectives. The type of research and classification of materials being studied will be addressed. This includes the recent emphasis being placed on nanomaterials and biomaterials type research. Materials Science Program will pursue a new, interdisciplinary approach, which contributes, to Human Space Flight Exploration research. The Materials Science Research Facility (MSRF) and other related American and International experiment modules will serve as the foundation for this research. Discussion will be included to explain the changing concept for materials science research processing capabilities aboard the ISS along with the various ground facilities necessary to support the program. Finally, the paper will address the initial utilization schedule and strategy for the various materials science payloads including their corresponding hardware.

Schlagheck, Ronald↗