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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 289 records · Page 16

Capturing, Analyzing, Maintaining, and Disseminating Shape Memory Material Data Between Information Management Systems

With an increased demand on reducing the time, cost, and effort to develop new materials, Integrated Computational Materials Engineering (ICME) has received widespread attention in various engineering disciplines as a catalyst for significantly reducing experimental testing during the material design process. An ICME approach to design can enable ‘fit-for-purpose’ materials to be realized in engineering applications by incorporating well-understood process-property-performance relationships between the various length and time scales in a material’s structure, enabling material optimization. However, such an approach requires validated multiscale models at the various length scales for a material, which in turn requires a large amount of data, a robust means of storing the data, and the ability to link data to developed material models. The NASA Vision 2040 [1] has identified nine key elements to enabling ICME approaches in system level design, with one being “Data, Information, and Visualization”, thus outlining the importance of a robust information management system for ICME. As the relationship between microstructure, properties, and material performance become better understood and incorporated into multiscale models that can be leveraged in application design, the emergence of new materials with application-driven properties can be realized. One such new material class that has seen growing attention are shape memory materials (SMM), in which a material can transition between a deformed and undeformed state via a reversible phase transformation when subject to a thermal, mechanical, or magnetic load [2]. SMMs have been used widely in aerospace and biomedical industries, including applications such as actuators, low-shock mechanisms, medical staples, braces, and stents [3, 4]. These materials exhibit unique behavior due to their ability to transition between phases, and thus the mechanisms that enable this transition must be captured in a data information management system and incorporated into SMM material models. At NASA Glenn Research Center, the Shape Memory Materials Database (SMMD) Tool has been developed to capture the necessary information that governs SMM material behavior and provide users the ability to select and visualize various SMMs for a specific application [5]. The database contains point-wise data for published SMM materials, along with the pedigree metadata for traceability necessary for a robust information management system. The database is also capable of storing in-house test data performed at NASA GRC by interacting with the developed Shape Memory Alloy (SMA) Analytics tool to extract the necessary point-wise values and populate the database. Although the SMMD Tool offers its users a single, authoritative source for SMM material data that is critical for model development and material design, the full material pedigree of the in-house test data for SMMs is not currently captured and is out of the scope for the SMMD tool. In this work, the schema for capturing SMM test data within the larger NASA GRC ICME Schema [6, 7, 8, 9] will be developed and implemented for thermomechanical tests conducted at NASA GRC. The developed schema will not only store the relevant data needed for the SMMD tool, but also the material pedigree (i.e., production of the bulk material, bulk material analysis, sample cut-out diagrams, sample fabrication procedure, etc.), test pedigree (i.e., test equipment used, measurement systems used, raw test data), and analysis pedigree (i.e., how the data in the SMMD tool is calculated). Furthermore, a Python-based framework will be developed to seamlessly interact between the SMA Analytics and SMMD tools, which will write the full dataset and associated metadata to the GRC Information Management System before passing the required point-wise data to the SMMD tool. Data informatics is a key element of the NASA Vision 2040, which requires not only that data is stored and maintained throughout the material lifecycle, but that the data is also accessible and reusable such that material development efforts can be minimized. Therefore, for an ICME design approach to be realized, a centralized information management system that drives the ICME process must be able to communicate with other databases. The work that will be presented in this presentation will therefore not only demonstrate the ability of NASA GRC’s information management system to capture SMM data, but also its ability to interact with pre-existing tools specialized for such materials.

Data management↗

Methods and devices for maintaining a resonant wavelength of a photonic microresonator

A photonic microresonator incorporates a localized heater element within a section of an optical bus waveguide that is in proximity to the resonator structure. The application of an adjustable control voltage to the heater element provides a localized change in the refractive index value of the bus waveguide, compensating for temperature-induced wavelength drift and maintaining a stabilized value of the microresonator's resonant wavelength.

36 MATERIALS SCIENCE↗

Store operations to maintain cache coherence

In one embodiment, a computer-implemented method includes encountering a store operation during a compile-time of a program, where the store operation is applicable to a memory line. It is determined, by a computer processor, that no cache coherence action is necessary for the store operation. A store-without-coherence-action instruction is generated for the store operation, responsive to determining that no cache coherence action is necessary. The store-without-coherence-action instruction specifies that the store operation is to be performed without a cache coherence action, and cache coherence is maintained upon execution of the store-without-coherence-action instruction.

97 MATHEMATICS AND COMPUTING↗

Store operations to maintain cache coherence

In one embodiment, a computer-implemented method includes encountering a store operation during a compile-time of a program, where the store operation is applicable to a memory line. It is determined, by a computer processor, that no cache coherence action is necessary for the store operation. A store-without-coherence-action instruction is generated for the store operation, responsive to determining that no cache coherence action is necessary. The store-without-coherence-action instruction specifies that the store operation is to be performed without a cache coherence action, and cache coherence is maintained upon execution of the store-without-coherence-action instruction.

97 MATHEMATICS AND COMPUTING↗

Method and system to maintain electrolyte stability for all-iron redox flow batteries

Methods and systems are provided which maintain the positive and negative electrolyte pH and stability of a redox flow battery through the use of electrochemical rebalancing cells. The electrochemical cells may be activated by applying an electrical load to affect changes to the pH of the electrolytes. The use of the electrochemical cells improves long term performance stability redox flow batteries by decreasing and/or eliminating Fe(OH)3 precipitation formation.

25 ENERGY STORAGE↗

Muon Monitor Data To Maintain The Quality Of The NuMI Neutrino Beam at Fermilab

The NuMI-AIP has been proposed to upgrade the NuMI target system for a 1-MW operation. The facility produces an intense muon neutrino beam by using a high power pion production target and a focusing magnetic horns for long baseline neutrino experiment. A muon monitor which measures muon beam profile, is a key beam element to maintain the quality of muon neutrino beam. The system will be upgraded for the high beam power operation. We studied the response of muon monitors with the proton beam power, proton beam position on the target, and focusing strength of the horn. The results were evaluated for future operations. The response function needs to be modeled by using Machine Learning algorithms which will be implemented into a muon monitor signal analyzer. The new analyzer will forecast the neutrino beam quality and control the beam position on the target if needed. Upgrading the helium gas handling system is the other key to improve the stability of the muon monitor signal. We will present the status of the upgrade plan.

43 PARTICLE ACCELERATORS↗

Maintaining the Stockpile

One of NNSA’s core missions is to ensure the United States maintains a safe, secure, and effective nuclear weapons stockpile through the application of unparalleled science, technology, engineering, and manufacturing. NNSA extends the service life of weapons that have reached the end of their original design life through Life Extension Programs (LEPs). Other modernization efforts include Alterations (ALTs), which do not change the weapon’s operational capabilities, and Modifications, which do change the weapon’s operational capabilities. NNSA also conducts surveillance and assessment to ensure that weapons currently in the stockpile remain safe, secure, and effective. Labs, plants, and sites across the Nuclear Security Enterprise work together on this enduring national security mission.

Source record↗

W87-1 Modification Program (Maintaining the Stockpile)

NNSA resumed work on a W78 warhead replacement, designated as the W87-1, in fiscal year (FY) 2019 following the 2018 Nuclear Posture Review. By replacing the legacy W78, the W87-1 will maintain continuity for the ground-based leg of the U.S. nuclear deterrent. The warhead is named the W87-1 to reflect that it has a similar primary design to the W87-0 and will fly in a similar reentry vehicle. The W87-1 is based on a previously-tested nuclear component and will include an insensitive high explosive primary that had been designed and tested with advanced safety features. The warhead will be fielded by FY 2030 on the U.S. Air Force (USAF)’s Ground Based Strategic Deterrent. The W87-1 will not provide new military capabilities, yet it will provide enhanced safety and security compared to the legacy W78. The W87-1 will be certified without the need for additional underground nuclear explosive testing.

Source record↗

W88 Alteration 370 (Maintaining the Stockpile)

The W88 nuclear warhead entered the stockpile in late 1988 and is deployed on the Navy’s Trident II D5 Submarine-Launched Ballistic Missile (SLBM) system, carried onboard Ohio-class ballistic missile submarines. Deployed now for almost three decades, several updates are required to address aging issues and to maintain its current state of readiness. The W88 Alteration (Alt) 370 program replaces the arming, fuzing, and firing subsystem, adds a lightning arrestor connector, and refreshes the conventional high explosives within the weapon to enhance nuclear safety and support future life extension program options. The W88 Alt 370 program is scheduled to be completed concurrent with planned exchanges of limited-life, or routinely replaced, components, including the gas-transfer system

Source record↗

Method and system to maintain electrolyte stability for all-iron redox flow batteries

Methods and systems are provided which maintain the positive and negative electrolyte pH and stability of a redox flow battery through the use of electrochemical rebalancing cells. The electrochemical cells may be activated by applying an electrical load to affect changes to the pH of the electrolytes. The use of the electrochemical cells improves long term performance stability redox flow batteries by decreasing and/or eliminating Fe(OH)3 precipitation formation.

25 ENERGY STORAGE↗

Conservation of Helium while Maintaining High System Purity

Recent helium shortages and helium price increases have lead to an increased emphasis being placed on conserving helium. The need to conserve helium must be balanced with need to maintain the high levels of purity necessary to prevent operational problems caused by contamination. Helium losses and contamination control are especially important for test stands that have cryogenic distribution systems operating continuously with frequent changeover of cryogenic temperature components that are being tested. This paper describes a mathematical model to estimate the quantity of helium lost and the purity of the helium after the pump and backfill procedure is complete. The process to determine the optimal time during pump down to cut off pumping and start backfilling is described. There is a tradeoff between trying to achieve the lowest possible pressure during pumping and the quantity of air leaking into the volume while pumping is occurring. An additional benefit of careful selection of pump and backfill parameters in conjunction with real-time pressure monitoring can reduce the labor and time required to complete a successful pump and backfill procedure. This paper is intended to be a tool for engineers to review their pump and backfill procedures and measured data to optimize helium losses, system purity, and labor required.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Issues about implementation of geometry control to maintain nuclear criticality safety - 14438

The control of the geometry to establish and maintain Nuclear Criticality Safety (NCS) of a fissile unit is usually preferred by licensees and regulators since such a control is based on passive engineering and requires less operating constraints than other methods of control (mass, etc.). Nevertheless, several safety issues are associated with this method of control to ensure the geometry during all the unit lifetime, in normal and abnormal situations, from its manufacturing to its decommissioning. The first issue is to identify the dimensions defining the geometry, taking into account reflectors and mobile equipment, and the interaction conditions of the controlled unit to ensure the subcriticality. Thus, the dimensions important and to be controlled are identified in the NCS assessment. These dimensions are called Nuclear Criticality Safety Dimensions (NCSD) in this paper. Then, the second and the third issues are to define NCSD limits to be respected and to verify the compliance of the actual unit geometry with these limits at each stage of the unit life. Regarding the third issue, the challenges are the practicality of the control, its uncertainty and the management of non-compliances. Finally, the fourth issue is to properly document and record the NCSD and the compliance verification. This paper focuses on the main issues related to the implementation of geometry control on the NCS assessment and suggests advices to fulfill these challenges. (authors)

42 ENGINEERING↗

Performance Versus Maintainability: A Case Study of Scream on Frontier

The Simple Cloud-Resolving E3SM Atmosphere Model (Scream) won the inaugural ACM Gordon Bell Prize for Climate Modeling. While most of Scream is portable Kokkos code, the Gordon-Bell runs did include tuning specifically for Frontier, the exascale computer at Oak Ridge National Laboratory. Production science runs use the same high-level configuration of Scream, but the tuned kernels do not meet the software standards necessary to merge into the production code base. This work describes experiments to refactor these kernels to meet the maintainability requirements of the production Scream code base while preserving high performance.

White, Trey↗

Radiation Protection Instrument Reliability and Maintainability Data

This report is a collection of reliability and maintenance data on several types of radiation protection instrumentation. Some radiation detectors are used for personnel safety; others are used for environmental stewardship. Six types of instruments are addressed in this report. These are: continuous air monitors, tritium room air monitors, facility vent stack monitors, tritium bubbler monitors, tritium in effluent water monitors, and general purpose radiation survey meters. Literature searches, operating experience data, and occurrence reports were used to identify failure modes and to estimate quantitative failure rates for several general types of radiation protection instruments. Likewise, data on instrument repair has been found when possible and used to estimate the mean time to repair. These data can be useful for facility safety assessment, personnel safety assessment, environment assessment, and for equipment and labor planning purposes.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗