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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 NTRS2013

JPL Mission Bibliometrics

For a number of years ongoing bibliographies of various JPL missions (AIRS, ASTER, Cassini, GRACE, Earth Science, Mars Exploration Rovers (Spirit & Opportunity)) have been compiled by the JPL Library. Mission specific bibliographies are compiled by the Library and sent to mission scientists and managers in the form of regular (usually quarterly) updates. Charts showing publications by years are periodically provided to the ASTER, Cassini, and GRACE missions for supporting Senior Review/ongoing funding requests, and upon other occasions as a measure of the impact of the missions. Basically the Web of Science, Compendex, sometimes Inspec, GeoRef and Aerospace databases are searched for the mission name in the title, abstract, and assigned keywords. All get coded for journal publications that are refereed publications.

Bibliographies↗

NASA NTRS2015

TankSIM: A Cryogenic Tank Performance Prediction Program

Accurate prediction of the thermodynamic state of the cryogenic propellants in launch vehicle tanks is necessary for mission planning and successful execution. Cryogenic propellant storage and transfer in space environments requires that tank pressure be controlled. The pressure rise rate is determined by the complex interaction of external heat leak, fluid temperature stratification, and interfacial heat and mass transfer. If the required storage duration of a space mission is longer than the period in which the tank pressure reaches its allowable maximum, an appropriate pressure control method must be applied. Therefore, predictions of the pressurization rate and performance of pressure control techniques in cryogenic tanks are required for development of cryogenic fluid long-duration storage technology and planning of future space exploration missions. This paper describes an analytical tool, Tank System Integrated Model (TankSIM), which can be used for modeling pressure control and predicting the behavior of cryogenic propellant for long-term storage for future space missions. It is written in the FORTRAN 90 language and can be compiled with any Visual FORTRAN compiler. A thermodynamic vent system (TVS) is used to achieve tank pressure control. Utilizing TankSIM, the following processes can be modeled: tank self-pressurization, boiloff, ullage venting, and mixing. Details of the TankSIM program and comparisons of its predictions with test data for liquid hydrogen and liquid methane will be presented in the final paper.

Bolshinskiy, L. G.↗

NASA NTRS2015

ESIP Earth Sciences Data Analytics (ESDA) Cluster - Work in Progress

The purpose of this poster is to promote a common understanding of the usefulness of, and activities that pertain to, Data Analytics and more broadly, the Data Scientist; Facilitate collaborations to better understand the cross usage of heterogeneous datasets and to provide accommodating data analytics expertise, now and as the needs evolve into the future; Identify gaps that, once filled, will further collaborative activities. Objectives Provide a forum for Academic discussions that provides ESIP members a better understanding of the various aspects of Earth Science Data Analytics Bring in guest speakers to describe external efforts, and further teach us about the broader use of Data Analytics. Perform activities that:- Compile use cases generated from specific community needs to cross analyze heterogeneous data- Compile sources of analytics tools, in particular, to satisfy the needs of the above data users- Examine gaps between needs and sources- Examine gaps between needs and community expertise- Document specific data analytics expertise needed to perform Earth science data analytics Seek graduate data analytics Data Science student internship opportunities.

science data analysis↗

NASA NTRS2016

Lessons Learned and Future Goals of the High Lift Prediction Workshops

The American Institute of Aeronautics and Astronautics (AIAA) High Lift Prediction Workshop series is described. Two workshops have been held to date. Major conclusions are summarized, and plans for future workshops are outlined. A compilation of lessons learned from the first two workshops is provided. This compilation includes a summary of needs for future high-lift experiments that are intended for computational fluid dynamics (CFD) validation.

Rumsey, Christopher L.↗

NASA NTRS2017

Tracking Historical NASA EVA Training: Lifetime Surveillance of Astronaut Health (LSAH) Development of the EVA Suit Exposure Tracker (EVA SET)

During a spacewalk, designated as extravehicular activity (EVA), an astronaut ventures from the protective environment of the spacecraft into the vacuum of space. EVAs are among the most challenging tasks during a mission, as they are complex and place the astronaut in a highly stressful environment dependent on the spacesuit for survival. Due to the complexity of EVA, NASA has conducted various training programs on Earth to mimic the environment of space and to practice maneuvers in a more controlled and forgiving environment. However, rewards offset the risks of EVA, as some of the greatest accomplishments in the space program were accomplished during EVA, such as the Apollo moonwalks and the Hubble Space Telescope repair missions. Water has become the environment of choice for EVA training on Earth, using neutral buoyancy as a substitute for microgravity. During EVA training, an astronaut wears a modified version of the spacesuit adapted for working in water. This high fidelity suit allows the astronaut to move in the water while performing tasks on full-sized mockups of space vehicles, telescopes, and satellites. During the early Gemini missions, several EVA objectives were much more difficult than planned and required additional time. Later missions demonstrated that "complex (EVA) tasks were feasible when restraints maintained body position and underwater simulation training ensured a high success probability".1,2 EVA training has evolved from controlling body positioning to perform basic tasks to complex maintenance of the Hubble Space Telescope and construction of the International Space Station (ISS). Today, preparation is centered at special facilities built specifically for EVA training, such as the Neutral Buoyancy Laboratory (NBL) at NASA's Johnson Space Center ([JSC], Houston) and the Hydrolab at the Gagarin Cosmonaut Training Centre ([GCTC], Star City, outside Moscow). Underwater training for an EVA is also considered hazardous duty for NASA astronauts. This activity places astronauts at risk for decompression sickness and barotrauma as well as various musculoskeletal disorders from working in the spacesuit. The medical, operational and research communities over the years have requested access to EVA training data to better understand the risks. As a result of these requests, epidemiologists within the Lifetime Surveillance of Astronaut Health (LSAH) team have compiled records from numerous EVA training venues to quantify the exposure to EVA training. The EVA Suit Exposure Tracker (EVA SET) dataset is a compilation of ground-based training activities using the extravehicular mobility unit (EMU) in neutrally buoyant pools to enhance EVA performance on orbit. These data can be used by the current ISS program and future exploration missions by informing physicians, researchers, and operational personnel on the risks of EVA training in order that future suit and mission designs incorporate greater safety. The purpose of this technical report is to document briefly the various facilities where NASA astronauts have performed EVA training while describing in detail the EVA training records used to generate the EVA SET dataset.

Laughlin, Mitzi S.↗

NASA NTRS2016

Landslides in West Coast Metropolitan Areas: The Role of Extreme Weather Events

Rainfall-induced landslides represent a pervasive issue in areas where extreme rainfall intersects complex terrain. A farsighted management of landslide risk requires assessing how landslide hazard will change in coming decades and thus requires, inter alia, that we understand what rainfall events are most likely to trigger landslides and how global warming will affect the frequency of such weather events. We take advantage of 9 years of landslide occurrence data compiled by collating Google news reports and of a high-resolution satellite-based daily rainfall data to investigate what weather triggers landslide along the West Coast US. We show that, while this landslide compilation cannot provide consistent and widespread monitoring everywhere, it captures enough of the events in the major urban areas that it can be used to identify the relevant relationships between landslides and rainfall events in Puget Sound, the Bay Area, and greater Los Angeles. In all these regions, days that recorded landslides have rainfall distributions that are skewed away from dry and low-rainfall accumulations and towards heavy intensities. However, large daily accumulation is the main driver of enhanced hazard of landslides only in Puget Sound. There, landslide are often clustered in space and time and major events are primarily driven by synoptic scale variability, namely "atmospheric rivers" of high humidity air hitting anywhere along the West Coast, and the interaction of frontal system with the coastal orography. The relationship between landslide occurrences and daily rainfall is less robust in California, where antecedent precipitation (in the case of the Bay area) and the peak intensity of localized downpours at sub-daily time scales (in the case of Los Angeles) are key factors not captured by the same-day accumulations. Accordingly, we suggest that the assessment of future changes in landslide hazard for the entire the West Coast requires consideration of future changes in the occurrence and intensity of atmospheric rivers, in their duration and clustering, and in the occurrence of short-duration (sub-daily) extreme rainfall as well. Major regional landslide events, in which multiple occurrences are recorded in the catalog for the same day, are too rare to allow a statistical characterization of their triggering events, but a case study analysis indicates that a variety of synoptic-scale events can be involved, including not only atmospheric rivers but also broader cold- and warm-front precipitation. That a news-based catalog of landslides is accurate enough to allow the identification of different landslide/ rainfall relationships in the major urban areas along the US West Coast suggests that this technology can potentially be used for other English-language cities and could become an even more powerful tool if expanded to other languages and non-traditional news sources, such as social media.

landslides↗

NASA NTRS2016

Predictions of Solar Cycle 24: How are We Doing?

Predictions of solar activity are an essential part of our Space Weather forecast capability. Users are requiring usable predictions of an upcoming solar cycle to be delivered several years before solar minimum. A set of predictions of the amplitude of Solar Cycle 24 accumulated in 2008 ranged from zero to unprecedented levels of solar activity. The predictions formed an almost normal distribution, centered on the average amplitude of all preceding solar cycles. The average of the current compilation of 105 predictions of the annual-average sunspot number is 106 +/- 31, slightly lower than earlier compilations but still with a wide distribution. Solar Cycle 24 is on track to have a below-average amplitude, peaking at an annual sunspot number of about 80. Our need for solar activity predictions and our desire for those predictions to be made ever earlier in the preceding solar cycle will be discussed. Solar Cycle 24 has been a below-average sunspot cycle. There were peaks in the daily and monthly averaged sunspot number in the Northern Hemisphere in 2011 and in the Southern Hemisphere in 2014. With the rapid increase in solar data and capability of numerical models of the solar convection zone we are developing the ability to forecast the level of the next sunspot cycle. But predictions based only on the statistics of the sunspot number are not adequate for predicting the next solar maximum. I will describe how we did in predicting the amplitude of Solar Cycle 24 and describe how solar polar field predictions could be made more accurate in the future.

Pesnell, William D.↗

NASA NTRS2016

Compatibility Assessment Tool

In support of ground system development for the Space Launch System (SLS), engineers are tasked with building immense engineering models of extreme complexity. The various systems require rigorous analysis of pneumatics, hydraulic, cryogenic, and hypergolic systems. There are certain standards that each of these systems must meet, in the form of pressure vessel system (PVS) certification reports. These reports can be hundreds of pages long, and require many hours to compile. Traditionally, each component is analyzed individually, often utilizing hand calculations in the design process. The objective of this opportunity is to perform these analyses in an integrated fashion with the parametric CADCAE environment. This allows for systems to be analyzed on an assembly level in a semi-automated fashion, which greatly improves accuracy and efficiency. To accomplish this, component specific parameters were stored in the Windchill database to individual Creo Parametric models based on spec control drawings. These parameters were then accessed by using the Prime Analysis within Creo Parametric. MathCAD Prime spreadsheets were created that automatically extracted these parameters, performed calculations, and generated reports. The reports described component compatibility based on local conditions such as pressure, temperature, density, and flow rates. The reports also determined component pairing compatibility, such as properly sizing relief valves with regulators. The reports stored the input conditions that were used to determine compatibility to increase traceability of component selection. The desired workflow for using this tool would begin with a Creo Schematics diagram of a PVS system. This schematic would store local conditions and locations of components. The schematic would then populate an assembly within Creo Parametric, using Windchill database parts. These parts would have their attributes already assigned, and the MathCAD spreadsheets could begin running through database parts to determine which components would be suited for specific locations within the assembly. This eliminates a significant amount of time from the design process, and makes initial analysis assessments more accurate. Each component that would be checked for a location within the assembly would generate a report, showing whether the component was compatible. These reports could be used to generate the PVS report without the need to perform the same analysis multiple times. This process also has the potential to be expanded upon to further automate PVS reports. The integration of software codes or macros could be used to automatically check through hundreds of parts for each location on the schematic. If the software could recognize which type of component would be necessary for each location, it is possible that simply starting the macro could completely choose all the components needed for the schematic, and in turn the system. This would save many hours of work initially selecting components, which could end up saving money. Overall, this process helps to automate initial component selections for PVS systems to fit local design specifications. These selections will automatically generate reports showing how the design criteria are met by the specific component that was chosen. These reports will contribute to easier compilation of the PVS certification reports, which currently take a great amount of time and effort to produce.

Egbert, James Allen↗

NASA NTRS2016

Expanded Benefits for Humanity from the International Space Station

In 2012, the International Space Station (ISS) partnership published the updated International Space Station Benefits for Humanity, 2nd edition, a compilation of stories about the many benefits being realized in the areas of human health, Earth observations and disaster response, and global education. This compilation has recently been revised to include updated statistics on the impacts of the benefits, and new benefits that have developed since the first publication. Two new sections have also been added to the book, economic development of space and innovative technology. This paper will summarize the updates on behalf of the ISS Program Science Forum, made up of senior science representatives across the international partnership. The new section on "Economic Development of Space" highlights case studies from public-private partnerships that are leading to a new economy in low earth orbit (LEO). Businesses provide both transportation to the ISS as well as some research facilities and services. These relationships promote a paradigm shift of government-funded, contractor-provided goods and services to commercially-provided goods purchased by government agencies. Other examples include commercial firms spending research and development dollars to conduct investigations on ISS and commercial service providers selling services directly to ISS users. This section provides examples of ISS as a test bed for new business relationships, and illustrates successful partnerships. The second new section, Innovative Technology, merges technology demonstration and physical science findings that promise to return Earth benefits through continued research. Robotic refueling concepts for life extensions of costly satellites in geo-synchronous orbit have applications to robotics in industry on Earth. Flame behavior experiments reveal insight into how fuel burns in microgravity leading to the possibility of improving engine efficiency on Earth. Nanostructures and smart fluids are examples of materials improvements that are being developed using data from ISS. The publication also expands the benefits of research results in human health, environmental change and disaster response and in education activities developed to capture student imaginations in support of science, technology, engineering and mathematics, or STEM, education internationally. Applications to human health of the knowledge gained on ISS continues to grow and improve healthcare technologies and our understanding of human physiology. Distinct benefits return to Earth from the only orbiting multi-disciplinary laboratory of its kind. The ISS is a stepping stone for future space exploration by providing findings that develop LEO and improve life on our planet.

Rai, Amelia↗

NASA NTRS2018

Assessing the Completeness of Occupational Exposure Data in the Lifetime Surveillance of Astronaut Health

INTRODUCTION: Longitudinal analysis on how spaceflight affects human health requires significant amounts of data. Missing data, especially if missing in a non-random fashion, could be a significant challenge to the success and validity of ongoing occupational surveillance and research. Astronaut occupational health data have been collected since 1959 in various formats and as part of several flight programs. As a result of changing methodologies over this span, epidemiologists in the NASA Lifetime Surveillance of Astronaut Health (LSAH) project regularly compile data sets with important exposure or outcome data missing. METHODS: NASA medical records of astronauts participating in voluntary annual LSAH examinations were reviewed and compiled to develop Individual Exposure Profiles (IEP) for each astronaut. These data were supplemented by an interview. If the interview yielded medically relevant information absent from the medical record, that information was considered an update. The IEPs were analyzed to identify trends regarding the characteristics of astronauts who provided updates and what kinds of information were consistently being updated. RESULTS: To date, 190 astronauts have participated in the IEP project. Medical information was updated for 119 individuals during these interviews. The astronauts' likelihood of updating their record upon interview was not significantly related to their spaceflight experience, era of active spaceflight, or duration of longest spaceflight. The most commonly updated categories of medical information were issues encountered during spaceflights, including CO2 symptoms, vision changes, back pain, headaches, and space motion sickness. DISCUSSION: The most commonly updated categories correspond to areas where LSAH has ongoing analysis efforts and therefore do not appear to have been reported at random. This presentation will address identification of missing astronaut health data and trends, forward work identified by the IEP project and how this information may be used for future LSAH data gap analyses.

Sieker, Jeremy↗

NASA NTRS2020

Julia Programming Language Benchmark Using a Flight Simulation

Julia is a relatively new computer language that aims to reduce the challenge for mathmodelers to develop fast computer tools and simulations. It potentially combines the ease-of-coding feature of scripting languages (like Python) with the performance of compiled languages (like C++). A key question for Julia application to the simulation domain is, “Can Julia, with its obvious coding simplicity, provide runtime speeds comparable to conventional compiled languages for flight simulation?” A unique combination of existing elements can be employed to address the previous question: Extensively documented object-oriented simulation architecture, Industry standard rocket flight simulation, Separate versions (C++, Java, and Python) already benchmarked.

Sells, Ray↗

NASA NTRS2019

Overview of Liner Activities in Support of the International Forum for Aviation Research

This paper provides an overview of liner research being conducted by members of the International Forum for Aviation Research (IFAR). The IFAR consists of representatives from a number of national research labs and is established to enable information exchange on aviation research activities. NASA has provided three challenges that explore different aspects of acoustic liner research, and will compile the results from each of the partners into a common database when the challenges are completed. The goal of the first challenge is to compare experimental methods applied at different national labs for acoustic liner evaluation, and to compare impedance eduction methodologies for uniform liners. The second challenge is to evaluate the ability of 3D propagation codes to predict the effects of spanwise variable-impedance liners on the acoustic pressure field. The third challenge is to explore different approaches to simultaneously educe the impedances for each zone of a three-zone liner. Each challenge is intended to be conducted as a blind test. Thus, only representative results achieved by the NASA Liner Physics Team for each of the three challenges are presented herein. When the results from all participants are available, the compiled results are intended to be provided in future reports.

Jones, Michael G.↗

NASA NTRS2020

Copilot 3

Ultra-critical systems require high-level assurance, which cannot always be guaranteed in compile time. The use of runtime verification (RV) enables monitoring these systems in runtime, to detect property violations early and limit their potential consequences. The introduction of monitors in ultra-critical systems poses a challenge, as failures and delays in the RV subsystem could affect other subsystems and threaten the mission as a whole. This paper presents Copilot 3, a runtime verification framework for real-time embedded systems. Copilot monitors are written in a compositional, stream-based language with support for a variety of Temporal Logics (TL), which results in robust, high-level specifications that are easier to understand than their traditional counterparts. The framework translates monitor specifications into C code with static memory requirements, which can be compiled to run on embedded hardware. This paper presents version 3 of the Copilot language, demonstrates its suitability with a number of examples, and discusses its use in larger applications. Additionally, it describes the framework?s architecture, its implementation as a Domain Specific Language (DSL) embedded in Haskell, and the progress of the project over the years.

Ivan Perez↗

NASA NTRS2019

TPSAS-NF1676L-32323-DND

The GSICS VIS/NIR subgroup has several items to discuss and to provide a brief summary of the GSICS VIS/NIR activities. The first item is currently using Aqua-MODIS as the visible calibration reference. The plan is to migrate to NPP-VIIRS as the visible calibration reference. Then official source is the NOAA NPP VIIRS dataset, which is only archived with V0. However, NOAA has updated the calibration known as V2. The specifics will be discussed of how to scale the V0 visible radiances to the V2 standard. Second item is to outline a deep convective cloud (DCC) paper visible calibration paper with input from the various agencies using the GSICS DCC calibration approach. Also, to finalize the solar spectra selection. Lastly, to start the conversation with Rayleigh scattering calibration. Several slides will be compile using conclusions from GSICS web meetings, which are compiled from input across multiple agencies. Topics include improvements in spectral band adjustment factors, desert calibration, and homogenization of data records.

David Doelling↗

NASA NTRS2020

Landslides Across the USA: Occurrence, Susceptibility, and Data Limitations

Detailed information about landslide occurrence is the foundation for advancing process understanding, susceptibility mapping, and risk reduction. Despite the recent revolution in digital elevation data and remote sensing technologies, landslide mapping remains resource intensive. Consequently, a modern, comprehensive map of landslide occurrence across the United States (USA) has not been compiled. As a first step toward this goal, we present a national-scale compilation of existing, publicly available landslide inventories. This geodatabase can be downloaded in its entirety or viewed through an online, searchable map, with parsimonious attributes and direct links to the contributing sources with additional details. The mapped spatial pattern and concentration of landslides are consistent with prior characterization of susceptibility within the conterminous USA, with some notable exceptions on the West Coast. Although the database is evolving and known to be incomplete in many regions, it confirms that landslides do occur across the country, thus highlighting the importance of our national-scale assessment. The map illustrates regions where high-quality mapping has occurred and, in contrast, where additional resources could improve confidence in landslide characterization. For example, borders between states and other jurisdictions are quite apparent, indicating the variation in approaches to data collection by different agencies and disparity between the resources dedicated to landslide characterization. Further investigations are needed to better assess susceptibility and to determine whether regions with high relief and steep topography, but without mapped landslides, require further landslide inventory mapping. Overall, this map provides a new resource for accessing information about known landslides across the USA.

Landslide mapping↗

NASA NTRSDate not supplied

Trends in Small Satellite Presentations from 2017-2019

As the small satellite community expands and new technologies emerge, it is important to understand and interpret these changes over time. In doing so, we observe progress and aid future development within the field. During the summer of 2020 we compiled for assessment purposes, archived presentation data for years 2017-2019 from three primary sources: the CubeSat Developers Workshop, Interplanetary Small Satellite Conference, and the Small Satellite Conference. A few examples of the information we recorded and compiled were presenter names and affiliations, presentation topic, and mission progress status. Ultimately, we reviewed roughly 600 presentations between the three conferences and the data obtained therein form the basis of our trend assessment. The paper focuses on trends interpreted through the assessment of key elements available in the content of each presentation to include: SmallSat mission developers, subsystem developments and the expanded scope for small satellite destinations. Data was generalized using various forms of analysis depending on the type of information being assessed. In the end, we achieved our goal of reducing the content to its key points and major takeaways from the conference proceedings. In this presentation, the observed trends in data and our findings will be discussed. First, we will cover changes in presentation topics by categorizing them as either: science, technology, science/technology, or other. Our next topic will be about the agencies and organizations at the forefront of small satellite research and development. The following section will explain trends in subsystem developments for telecommunications, propulsion, power, and thermal management. Further discussion will highlight how the scope of interplanetary spaceflight has expanded since 2017 as new small spacecraft missions venture beyond low-Earth orbit into deep space exploration. And finally, we will observe what information was lacking in archived presentations which included but not limited to: mission’s funding source, presentation focus area, and software used.

Small Satellite↗

NASA NTRSDate not supplied

Trends in Small Satellite Presentations from 2017 - 2019

Small Satellites↗

NASA NTRS2021

Commercial Hypersonic Transportation Market Study

At the request of NASA, Deloitte conducted an independent market study to provide an independent assessment on the economic viability of hypersonic and supersonic air transportation to inform ongoing strategic planning of research areas within the government and industry and to focus on the areas for technology development and vehicle design requirements. The Study was organized into three primary areas of investigation: Defining the Market appetite for high speed air transport, Defining the business cases; and Assessing Barriers in the environment. The market demand was assessed across a range of Mach numbers from Mach 2 to Mach 6 and ticket price elasticity was determined by surveying potential customers, literature reviews and stakeholder and expert interviews for passenger aircraft, private aircraft and cargo markets. The business case analyses assessed potential business cases across a three-dimensional trade space: flight speed (Mach 2-6), passenger capacity (20-200 passengers) and design range (2500-7500 nmi.). By using the SpaceWorks Rosetta model, we were able to assess each combination in the trade space and to determine the steady state Internal Rate of Return (IRR or profit) was our primary figure of merit and allowed us to rank order the business cases to understand the trends and draw conclusions from the complex trade space. Lastly, we assessed other potential barriers to high speed flight. These were determined through literature review and stakeholder/expert interviews. Once these were compiled, we developed an objective scoring system to allow us to determine overall significance and challenge to aspiring market entrants. The majority of the research was conducted between July and December of 2020 and the results compiled and communicated to NASA in the first quarter of calendar year 2021. This report, along with the companion briefing deck, document the summation of our research and serve as a data repository for use by future researchers in government and industry.

hypersonic aircraft↗