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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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NASA NTRSDate not supplied

Publishing Variables Archived at GES DISC to Earth System Grid Federation (ESGF)

We present a straightforward and low-cost approach to publish variables archived at NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) to the Earth System Grid Federation (ESGF). An ESGF publication requires a single standard-name variable aggregated over time to facilitate data inter-comparison. It also contains significant metadata to enable searching in ESGF. We look up standard names on high demand in ESGF search history, and using OPeNDAP and NcML technologies we aggregate the corresponding variables available in the GES DISC archive with augmented metadata required by CMIP6 and obs4MIPs Data Specification version 2.1. At this writing 10 variables from a standard product of the Atmospheric Infrared Sounder along with the Tech Notes are published in ESGF by NASA Center for Climate Simulation (NCCS). Users can view, analyze, and subset remotely, and download these aggregated variables via links in any ESGF node after searching. We plan to work on and publish more variables and data from different NASA missions and experiments in our archive.

Fan Fang↗
DOE OSTI2023

A Systematic Investigation of the Effects of Standard-Sample Concentration Mismatch during Fe Isotope Measurement by MC-ICP-MS

Advances in multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS) have led to the widespread use of iron (Fe) isotopes to elucidate the (bio)geochemical history of a range of environments. To generate Fe isotope ratio measurements, standard-sample bracketing (SSB) is commonly used to correct for instrumental mass bias inherent to MC-ICP-MS. However, SSB is only accurate when sample and isotope standard Fe concentrations match, in addition to the bulk solution matrix. When the Fe concentrations differ, Fe isotope ratio measurement results may be inaccurate, a phenomenon known as the "self-induced matrix effect." Here, this study systematically characterised the self-induced matrix effect for dry plasma Fe isotope ratio measurements on three MC-ICP-MS instruments and three introduction systems. Our extensive dataset indicates that: (1) the degree of mass bias is consistent regardless of MC-ICP-MS front-end design, (2) the degree of mass bias becomes less reproducible as the concentration difference between the sample and bracketing standard increases, and (3) this applies to both pure Fe solutions and solutions from geological materials. This study reinforces the requirement to match bracketing standard and sample concentrations within 10% and provides a correction method for that fall beyond the recommended concentration range to subsequently allow for proper concentration matching during SSB.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS2019

Orbital Debris Ontology, Terminology, and Knowledge Modeling

The looming threat orbital debris poses to assets in orbit demands solutions. As the orbital population grows, so does this hazard, but so does the sea of data. The problem is also an opportunity for interdisciplinary innovation and cooperation. This paper focuses on the data and information management aspect of developing solutions for a sustainable and safe orbital space environment. The corresponding author’s in-progress work to develop an orbital debris domain ontology is summarized in order to discuss knowledge modeling for this domain. Methodological approaches of this effort can also contribute to standards efforts and address terminological and policy questions. Leveraging the growing volumes of orbital debris and space situational awareness (SSA) data will create a more complete picture of the orbital space environment. Part of the solution will be: consistent and correct data interpretation, sharing orbital debris and SSA data in one form or another, terminology development & harmonization, and knowledge or domain modeling. To facilitate this, [Rovetto, 2015/16] discussed ontology development for the orbital debris domain. This paper lists concepts from that paper, and subsequently developed concepts [2-9]. Ontology engineering is an interdisciplinary field related to knowledge representation and reasoning in artificial intelligence, semantic technologies and the so-called semantic web. An ontology is effectively a computable and semantically rich terminology that presents a knowledge or domain model for a topic area. Expressions of knowledge or assertions are stored using formally defined term. This knowledge base is reasoned over to yield answers to queries, among other things. Ontologies have been developed in knowledge-based projects across various disciplines, and used for such things as search engines, chatbots, enterprise knowledge graphs, etc. Ontologies support: interoperability, automated reasoning, data sharing and integration, data search and retrieval, and communicating the meaning of data. The Orbital Debris Ontology (ODO), and related ontologies [Rovetto & Kelso 2016] [Rovetto 2016, 2017], were proposed to help achieve this. ODO, for instance, is intended as a domain ontology that can be used across federated databases, offering an explicitly specified set of concepts describing the orbital debris domain. Its meaning-rich taxonomy will provide a sharable semantics for orbital debris data to, in part, consistently communicate the meaning of data to both humans and machines, and tag data elements in space object catalogs to help afford inference tasks, decision support, knowledge discovery, and information integration. ODO and the SSA ontology (SSAO) is part of the overall Orbital Space Domain Ontology concept, which is conceived as a broader domain reference ontology. It aims to provide a knowledge representation structure of the orbital space environment, a common semantic model, and develop a sharable terminology. Collectively this will provide common meaning for datasets, a high-level taxonomy or classification for orbital space objects, and thus means to characterize space objects. Ongoing efforts have included using visualizations, R, JSON-LD, and contemporary semantic technologies. Potential applications and interdisciplinary partnerships include web-based platforms, web apps, visualizations, and academia projects. Community input and participation may yield a more widely understood domain model as well as facilitate terminological standards. For example, the proposed conceptual, terminological and ontological analysis may contribute to such efforts as the Space Debris Mitigation Requirements in the International Standards Organization by developing more precise, consistent and coherent terms and definitions. Projects that seek to develop in-house ontologies can use ODO and related ontologies as domain reference ontologies. This paper was developed independent of author affiliations. Readers are encouraged to contact corresponding author(1) with general interest and potential opportunities to support or realize the described project.

Robert J. Rovetto↗
DOE OSTI2025

Continued Testing and Modeling of the AirSquared All-Metal Tritium Scroll Pump

The implementation of fusion energy requires the processing of the deuterium-tritium mixture used to fuel the reaction. Many gas processing operations require either a gas-motive force or a pressure gradient across a system; both are achieved using vacuum pumps. However, because of the material challenges of working with tritium, specialized pumps are required that use only metal on wetted surfaces. This prevents tritium retention and degradation of materials such as oils and polymers and reduces the generation of tritiated waste. Typical gas handling systems for tritium operations involve metal bellows pumps, all-metal scroll pumps, and metal turbomolecular pumps, depending on the pressure requirements. With the industry standard Normetex Type 15 m 3 /h (typically referred to as the Normetex 15) pump no longer available, the fusion market requires viable alternatives. In this study, we test an American-made pump, the AirSquared V16H034A-C01, and compare its performance to the Normetex. A performance model of the AirSquared pump is also produced, which can be applied to general process models to generate an accurate description of pressures and flows through various unit operations.

08 HYDROGEN↗
NASA NTRS2004

The Precession Index and a Nonlinear Energy Balance Climate Model

A simple nonlinear energy balance climate model yields a precession index-like term in the temperature. Despite its importance in the geologic record, the precession index e sin (Omega)S, where e is the Earth's orbital eccentricity and (Omega)S is the Sun's perigee in the geocentric frame, is not present in the insolation at the top of the atmosphere. Hence there is no one-for-one mapping of 23,000 and 19,000 year periodicities from the insolation to the paleoclimate record; a nonlinear climate model is needed to produce these long periods. A nonlinear energy balance climate model with radiative terms of form T n, where T is surface temperature and n less than 1, does produce e sin (omega)S terms in temperature; the e sin (omega)S terms are called Seversmith psychroterms. Without feedback mechanisms, the model achieves extreme values of 0.64 K at the maximum orbital eccentricity of 0.06, cooling one hemisphere while simultaneously warming the other; the hemisphere over which perihelion occurs is the cooler. In other words, the nonlinear energy balance model produces long-term cooling in the northern hemisphere when the Sun's perihelion is near northern summer solstice and long-term warming in the northern hemisphere when the aphelion is near northern summer solstice. (This behavior is similar to the inertialess gray body which radiates like T 4, but the amplitude is much lower for the energy balance model because of its thermal inertia.) This seemingly paradoxical behavior works against the standard Milankovitch model, which requires cool northern summers (Sun far from Earth in northern summer) to build up northern ice sheets, so that if the standard model is correct it must be more efficient than previously thought. Alternatively, the new mechanism could possibly be dominant and indicate southern hemisphere control of the northern ice sheets, wherein the southern oceans undergo a long-term cooling when the Sun is far from the Earth during northern summer. The cold water eventually flows north, cooling the northern hemisphere. This might explain why the northern oceans lag the southern ones when it comes to orbital forcing.

Rubincam, David↗
NASA NTRS2017

International Standard Payload Rack to International Space Station, Software Interface Control Document Part 1: International Space Station Program Revision M

The purpose of this document is to provide definition of the software interface requirements between the International Standard Payload Rack (ISPR) plus C&DH related non-rack end items and the International Space Station (ISS) flight elements. Related non-rack end items include portable payloads in any of the modules, payloads on the Japanese Experiment Module Exposed Facility (JEM EF), payloads on the Columbus Exposed Payload Facility (COL EPF), and attached payloads mounted on the ISS truss.

Nelson, George C.↗
NASA NTRS1993

Optical media standards for industry

Optical storage is a new and growing area of technology that can serve to meet some of the mass storage needs of the computer industry. Optical storage is characterized by information being stored and retrieved by means of diode lasers. When most people refer to optical storage, they mean rotating disk media, but there are 1 or 2 products that use lasers to read and write to tape. Optical media also usually means removable media. Because of its removability, there is a recognized need for standardization, both of the media and of the recording method. Industry standards can come about in one or more different ways. An industry supported body can sanction and publish a formal standard. A company may ship enough of a product that it so dominates an application or industry that it acquires 'standard' status without an official sanction. Such de facto standards are almost always copied by other companies with varying degrees of success. A governmental body can issue a rule or law that requires conformance to a standard. The standard may have been created by the government, or adopted from among many proposed by industry. These are often known as de jure standards. Standards are either open or proprietary. If approved by a government or sanctioning body, the standard is open. A de facto standard may be either open or proprietary. Optical media is too new to have de facto standards accepted by the marketplace yet. The proliferation of non-compatible media types in the last 5 years of optical market development have convinced many of the need for recognized media standards.

Hallam, Kenneth J.↗
NASA NTRS2006

Guidelines for the Utilization of Composite Materials in Oxygen Storage Tanks

Space travel is inherently dangerous and, currently, quite expensive. NASA has always done everything possible to minimize the risk associated with the materials chosen for space travel applications by requiring that all materials associated with NASA programs meet the strict requirements established by NASA testing standard NASA-STD-600 1 Flammability, Odor, Offgassing, and Compatibility Requirements and Test Procedures for Materials in Environments that Support Combustion. NASA also has the need to develop lighter weight structural materials that will allow more payload weight to be carried into space. NASA is utilizing composite materials inside the orbiter to lighten the overall weight, but has not considered composite materials for oxygen tanks because of the inherent incompatibility of composite materials with atomic oxygen. This presentation will focus on how oxygen tanks can be built from composite materials. Details will be provided for the design and compatibility testing techniques that will be utilized to create a new NASA standard, NASA-HDBK-6018, which will serve as the starting point for the design of oxygen tanks made from composite materials.

Davis, Samuel E.↗
NASA NTRS2015

Cryogenic Insulation Standard Data and Methodologies Project

Extending some recent developments in the area of technical consensus standards for cryogenic thermal insulation systems, a preliminary Inter-Laboratory Study of foam insulation materials was performed by NASA Kennedy Space Center and LeTourneau University. The initial focus was ambient pressure cryogenic boil off testing using the Cryostat-400 flat-plate instrument. Completion of a test facility at LETU has enabled direct, comparative testing, using identical cryostat instruments and methods, and the production of standard thermal data sets for a number of materials under sub-ambient conditions. The two sets of measurements were analyzed and indicate there is reasonable agreement between the two laboratories. Based on cryogenic boiloff calorimetry, new equipment and methods for testing thermal insulation systems have been successfully developed. These boiloff instruments (or cryostats) include both flat plate and cylindrical models and are applicable to a wide range of different materials under a wide range of test conditions. Test measurements are generally made at large temperature difference (boundary temperatures of 293 K and 78 K are typical) and include the full vacuum pressure range. Results are generally reported in effective thermal conductivity (ke) and mean heat flux (q) through the insulation system. The new cryostat instruments provide an effective and reliable way to characterize the thermal performance of materials under subambient conditions. Proven in through thousands of tests of hundreds of material systems, they have supported a wide range of aerospace, industry, and research projects. Boiloff testing technology is not just for cryogenic testing but is a cost effective, field-representative methodology to test any material or system for applications at sub-ambient temperatures. This technology, when adequately coupled with a technical standards basis, can provide a cost-effective, field-representative methodology to test any material or system for applications at sub-ambient to cryogenic temperatures. A growing need for energy efficiency and cryogenic applications is creating a worldwide demand for improved thermal insulation systems for low temperatures. The need for thermal characterization of these systems and materials raises a corresponding need for insulation test standards and thermal data targeted for cryogenic-vacuum applications. Such standards have a strong correlation to energy, transportation, and environment and the advancement of new materials technologies in these areas. In conjunction with this project, two new standards on cryogenic insulation were recently published by ASTM International: C1774 and C740. Following the requirements of NPR 7120.10, Technical Standards for NASA Programs and Projects, the appropriate information in this report can be provided to the NASA Chief Engineer as input for NASA's annual report to NIST, as required by OMB Circular No. A-119, describing NASA's use of voluntary consensus standards and participation in the development of voluntary consensus standards and bodies.

Technology Portfolio System↗
DOE OSTI2023

Comparative Analysis of Standard and Advanced USL Methodologies for Nuclear Criticality Safety

The American National Standards Institute/American Nuclear Society national standards 8.1 and 8.24 provide guidance on the requirements and recommendations for establishing confidence in the results of the computerized models used to support operation with fissionable materials. By design, the guidance is not prescriptive, leaving freedom to the analysts to determine how the various sources of uncertainties are to be statistically aggregated. Due to the involved use of statistics entangled with heuristic recipes, the resulting safety margins are often difficult to interpret. Also, these technical margins are augmented by additional administrative margins, which are required to ensure compliance with safety standards or regulations, eliminating the incentive to understand their differences. With the new resurgent wave of advanced nuclear systems, e.g., advanced reactors, fuel cycles, and fuel concepts, focused on economizing operation, there is a strong need to develop a clear understanding of the uncertainties and their consolidation methods to reduce them in manners that can be scientifically defended. In response, the current studies compare the analyses behind four notable methodologies for upper subcriticality limit estimation that have been documented in the nuclear criticality safety literature: the parametric, nonparametric, Whisper, and TSURFER methodologies. Specifically, the work offers a deep dive into the various assumptions of the noted methodologies, their adequacies, and their limitations to provide guidance on developing confidence for the emergent nuclear systems that are expected to be challenged by the scarcity of experimental data. Here, to limit the scope, the current work focuses on the application of these methodologies to criticality safety experiments, where the goal is to calculate a bias, a bias uncertainty, and a tolerance limit for k eff in support of determining an upper subcriticality limit for nuclear criticality safety.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
NASA NTRS1975

Detailed requirements document for the problem reporting data system (PDS)

The system is described as a computer-based system designed to track the status of problems and corrective actions pertinent to space shuttle hardware. The input, processing, output, and performance requirements of the system are presented along with standard display formats and examples. Operational requirements, hardware, requirements, and test requirements are also included.

West, R. S.↗
NASA NTRS1989

Spacelab system analysis: The modified free access protocol: An access protocol for communication systems with periodic and Poisson traffic

The protocol definition and terminal hardware for the modified free access protocol, a communications protocol similar to Ethernet, are developed. A MFA protocol simulator and a CSMA/CD math model are also developed. The protocol is tailored to communication systems where the total traffic may be divided into scheduled traffic and Poisson traffic. The scheduled traffic should occur on a periodic basis but may occur after a given event such as a request for data from a large number of stations. The Poisson traffic will include alarms and other random traffic. The purpose of the protocol is to guarantee that scheduled packets will be delivered without collision. This is required in many control and data collection systems. The protocol uses standard Ethernet hardware and software requiring minimum modifications to an existing system. The modification to the protocol only affects the Ethernet transmission privileges and does not effect the Ethernet receiver.

Ingels, Frank↗
DOE OSTI2020

Recommendations for Data-in-Transit Requirements for Securing DER Communications

With the adoption of Distributed Energy Resource (DER) interoperability standards, common communication protocols are now being deployed between power system operators and DER devices. In 2018, a revision to the US interconnection and interoperability standard, Institute of Electrical and Electronics Engineers (IEEE) Std. 1547, required DER equipment to have an IEEE 2030.5, IEEE 1815, or SunSpec Modbus communication exchange interface. This change supports the future transition to secure connection and exchange of information between the DER equipment and implementing parties, such as grid operators. Adoption of standardized communication protocols and associated information models is a critical step toward interoperability between power system operators and DER, such as photovoltaic (PV) and energy storage systems. However, security requirements for these standardized communication protocols are not comprehensive, resulting in non-standard and vendor-specific implementation that may leave DER equipment susceptible to cyberattacks. This paper examines the data-in-flight security requirements for standardized DER communication protocols, per IEEE 1547-2018 revision, as it relates to device authentication, key management, and encryption. The state of the art for these security features is also explored, addressing their impact on communication and performance of low-cost single board computers, which are typical of DER devices. In conclusion, a recommendation is provided to adopt a common set of communication requirements, which are intended to achieve interoperability and implement data security over DER network pathways, while ensuring reliable, secure, and real-time information delivery.

42 ENGINEERING↗
NASA NTRS2019

Improving the Nuclear Launch Approval Process; Progress and Plans

Launches involving radioisotope power systems (RPS) or radioisotope heater units (RHU’s) must comply with a number of different statutory, regulatory, and administrative requirements. While some of these are well defined, others have been carried out on the basis of past practice rather than a set of formal standards. In addition, some of the requirements reference outdated standards and are in need of updates. The overall process is also time consuming and expensive. This paper describes efforts by NASA, the Department of Energy (DOE) and others to make improvements to the process while maintaining safety and environmental protection.

McCallum, Peter↗
NASA NTRS2007

Revitalization of Space-Related Human Factors, Environmental and Habitability Data

The NASA Chief Health and Medical Officer (CHMO) recently directed that the agency establish crew health standards to aid in the development of requirements for future vehicles and habitats. Response to this direction includes development of a new NASA habitability and human factors standard and an accompanying design handbook. The new standard contains high-level, over-arching principles to assure its applicability and usability across all NASA development programs. The handbook will provide detailed design requirements and suggestions that will meet the standards. The information contained in NASA-STD-3000 will be updated and included in the new design handbook. In this approach, each new program will derive detailed program-specific requirements from the new standard using the handbook as a design guide and resource. With the completion of the standard, the focus of this year s effort is the development of the new handbook: Human Integration Design Handbook (HIDH). This is an opportunity for the space flight human factors and habitability community to consolidate up-to-date data for use by NASA programs and designers as well as outside researchers and policy makers looking for the next research focus. The goal of the handbook is to help NASA design and build human space flight systems which accommodate the capabilities and limitations of the crew so as to provide an environment where the crew can live and work effectively, safely, and comfortably. Handbook contents will address that primary goal, addressing unique aspects of space flight and habitation, including reduced gravity conditions, time lags, EVA systems and day/night cycles, not addressed in other standards or handbooks. The handbook will be divided into topics similar to NASA-STD-3000 (anthropometrics, architecture, workstations, etc.) and each topic area will contain elements for designers, human factors practitioners, program managers, operators, and researchers. The handbook will include the following elements: (1) Design considerations include a clear and concise summary of what is important to designers in space vehicle / habitat design, design information to translate Earth-base knowledge to the space environment, space issues and the data necessary to address those issues, and a consistent set of terminology. (2) Updates to Lessons Learned and example solutions from Shuttle and Station program experience will provide historical examples to help prevent repeating mistakes or reinvention of the wheel. (3) Requirements will aid in the translation of standards into program specific requirements. The scope of included requirements will define the pool that each program needs to consider and tailor for their specific program. (4) Requirements rationale will help understanding of the importance of these considerations. The HIDH development team at JSC is finalizing the format of the new handbook, prioritizing topic areas for expansion and update, and contacting subject matter experts within the scientific community to assist with this effort. Plans are also being made to continue handbook expansion and maintenance to assure it remains a valuable resource for human factors and human space flight programs.

Russo, Dane↗
NASA NTRS1985

NASA/aircraft industry standard specification for graphite fiber toughened thermoset resin composite material

A standard specification for a selected class of graphite fiber/toughened thermoset resin matrix material was developed through joint NASA/Aircraft Industry effort. This specification was compiled to provide uniform requirements and tests for qualifying prepreg systems and for acceptance of prepreg batches. The specification applies specifically to a class of composite prepreg consisting of unidirectional graphite fibers impregnated with a toughened thermoset resin that produce laminates with service temperatures from -65 F to 200 F when cured at temperatures below or equal to 350 F. The specified prepreg has a fiber areal weight of 145 g sq m. The specified tests are limited to those required to set minimum standards for the uncured prepreg and cured laminates, and are not intended to provide design allowable properties.

Source record↗
DOE OSTI2020

Simulations of short-term exposure to NO 2 and PM 2.5 to inform capture efficiency standards

The California building code requires all new or renovated residential dwelling units to have kitchen exhaust ventilation to manage air pollutants and moisture generated during cooking. Current performance requirements are specified as a minimum airflow and maximum sound level. This report presents an analysis to support consideration of adding a capture efficiency requirement to the code. The analysis uses a physics-based simulation model to calculate air pollutant concentrations in homes that result from cooking and the inflow of outdoor air, mediated by loss and removal process including deposition, dwelling unit ventilation, and the use of a range hood with varying levels of capture efficiency. Calculated pollutant concentrations are compared to relevant, health-based guidelines. The analysis considers the highest 1-hour concentration of nitrogen dioxide (NO 2 ), which is a product of natural gas combustion and the highest 24-hour concentrations of fine particulate matter (PM 2.5 ) which is emitted in substantial quantities from frying, broiling and grilling among other cooking activities. For NO 2 , the analysis considers cooking of a dinner for 3-4 persons consisting of pasta, meat sauce, a par-boiled vegetable, and baked garlic bread. For PM 2.5 , the analysis considers a day in which breakfast emitted particles at the 80th percentile and lunch and dinner entailed particle emissions at the 50th percentile of cooking emission events reported in the literature. Model simulations were performed to determine the level of range hood capture efficiency that will allow these cooking scenarios to occur in the vast majority (>99%) of new homes being built in California while maintaining pollutant concentrations below the health-based guidelines, if the range hood is used throughout cooking. All homes were assumed to have dwelling unit ventilation at the rate required in the building code. Simulation model input parameters were specified using a Monte Carlo approach to represent a range of housing characteristics, outdoor conditions, and indoor pollutant dynamics. Simulation results suggest that requiring a minimum capture efficiency of at least 70% is needed to avoid unacceptably high NO 2 (1-h average concentration of 100 ppb or higher) and at least 60% to avoid unacceptably high PM 2.5 (24-h average of 25 μg/m³ or higher). These results were driven by multi-family homes, which have a smaller volume of air to dilute any pollutants not captured and removed at the cooking area, resulting in higher concentrations.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1979

Spacecraft charging standard

The spacecraft charging protection requirements for space vehicles which are to operate in the magnetospheric plasma environment are presented.

Holman, A. B.↗