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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 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS2005

NASA Research Center Contributions to Space Shuttle Return to Flight (SSRTF)

Contributions provided by the NASA Research Centers to key Space Shuttle return-to-flight milestones, with an emphasis on debris and Thermal Protection System (TPS) damage characterization, are described herein. Several CAIB recommendations and Space Shuttle Program directives deal with the mitigation of external tank foam insulation as a debris source, including material characterization as well as potential design changes, and an understanding of Orbiter TPS material characteristics, damage scenarios, and repair options. Ames, Glenn, and Langley Research Centers have performed analytic studies, conducted experimental testing, and developed new technologies, analysis tools, and hardware to contribute to each of these recommendations. For the External Tank (ET), these include studies of spray-on foam insulation (SOFI), investigations of potential design changes, and applications of advanced non-destructive evaluation (NDE) technologies to understand ET TPS shedding during liftoff and ascent. The end-to-end debris assessment included transport analysis to determine the probabilities of impact for various debris sources. For the Orbiter, methods were developed, and validated through experimental testing, to determine thresholds for potential damage of Orbiter TPS components. Analysis tools were developed and validated for on-orbit TPS damage assessments, especially in the area of aerothermal environments. Advanced NDE technologies were also applied to the Orbiter TPS components, including sensor technologies to detect wing leading edge impacts during liftoff and ascent. Work is continuing to develop certified TPS repair options and to develop improved methodologies for reinforced carbon-carbon (RCC) damage progression to assist in on-orbit repair decision philosophy.

Cockrell, Charles E., Jr.↗
NASA NTRS2012

NASA Tech Briefs, June 2012

Topics covered include: iGlobe Interactive Visualization and Analysis of Spatial Data; Broad-Bandwidth FPGA-Based Digital Polyphase Spectrometer; Small Aircraft Data Distribution System; Earth Science Datacasting v2.0; Algorithm for Compressing Time-Series Data; Onboard Science and Applications Algorithm for Hyperspectral Data Reduction; Sampling Technique for Robust Odorant Detection Based on MIT RealNose Data; Security Data Warehouse Application; Integrated Laser Characterization, Data Acquisition, and Command and Control Test System; Radiation-Hard SpaceWire/Gigabit Ethernet-Compatible Transponder; Hardware Implementation of Lossless Adaptive Compression of Data From a Hyperspectral Imager; High-Voltage, Low-Power BNC Feedthrough Terminator; SpaceCube Mini; Dichroic Filter for Separating W-Band and Ka-Band; Active Mirror Predictive and Requirement Verification Software (AMP-ReVS); Navigation/Prop Software Suite; Personal Computer Transport Analysis Program; Pressure Ratio to Thermal Environments; Probabilistic Fatigue Damage Program (FATIG); ASCENT Program; JPL Genesis and Rapid Intensification Processes (GRIP) Portal; Data::Downloader; Fault Tolerance Middleware for a Multi-Core System; DspaceOgreTerrain 3D Terrain Visualization Tool; Trick Simulation Environment 07; Geometric Reasoning for Automated Planning; Water Detection Based on Color Variation; Single-Layer, All-Metal Patch Antenna Element with Wide Bandwidth; Scanning Laser Infrared Molecular Spectrometer (SLIMS); Next-Generation Microshutter Arrays for Large-Format Imaging and Spectroscopy; Detection of Carbon Monoxide Using Polymer-Composite Films with a Porphyrin-Functionalized Polypyrrole; Enhanced-Adhesion Multiwalled Carbon Nanotubes on Titanium Substrates for Stray Light Control; Three-Dimensional Porous Particles Composed of Curved, Two-Dimensional, Nano-Sized Layers for Li-Ion Batteries 23 Ultra-Lightweight; and Ultra-Lightweight Nanocomposite Foams and Sandwich Structures for Space Structure Applications.

Source record↗
NASA NTRS2022

An Overview of Atmospheric Features Over the Western North Atlantic Ocean and North American East Coast – Part 1: Analysis of Aerosols, Gases, and Wet Deposition Chemistry

The Western North Atlantic Ocean (WNAO) and adjoining East Coast of North America are of great importance for atmospheric research and have been extensively studied for several decades. This broad region exhibits complex meteorological features and a wide range of conditions associated with gas and particulate species from many sources regionally and other continents. As Part 1 of a 2‐part paper series, this work characterizes quantities associated with atmospheric chemistry, including gases, aerosols, and wet deposition, by analyzing available satellite observations, ground‐based data, model simulations, and reanalysis products. Part 2 provides insight into the atmospheric circulation, boundary layer variability, three‐dimensional cloud structure, properties, and precipitation over the WNAO domain. Key results include spatial and seasonal differences in composition along the North American East Coast and over the WNAO associated with varying sources of smoke and dust and meteorological drivers such as temperature, moisture, and precipitation. Spatial and seasonal variations of tropospheric carbon monoxide and ozone highlight different pathways towards the accumulation of these species in the troposphere. Spatial distributions of speciated aerosol optical depth and vertical profiles of aerosol mass mixing ratios show a clear seasonal cycle highlighting the influence of different sources in addition to the impact of intercontinental transport. Analysis of long‐term climate model simulations of aerosol species and satellite observations of carbon monoxide confirm that there has been a significant decline in recent decades among anthropogenic constituents owing to regulatory activities.

ACTIVATE↗
NASA NTRS1972

Study of short haul high-density V/STOL transportation systems. Volume 2: Appendices

Essential supporting data to the short haul transportation study are presented. The specific appendices are arena characteristics, aerospace transportation analysis computer program, economics, model calibration, STOLport siting and services path selection, STOL schedule definition, tabulated California corridor results, and tabulated Midwest arena results.

Solomon, H. L.↗
NASA NTRS1972

American Airlines Propeller STOL Transport Economic Risk Analysis

A Monte Carlo risk analysis on the economics of STOL transports in air passenger traffic established the probability of making the expected internal rate of financial return, or better, in a hypothetical regular Washington/New York intercity operation.

Ransone, B.↗
NASA NTRS1976

Improved space radiation shielding methods

The computing software that was used to perform the charged particle radiation transport analysis and shielding design for the Mariner Jupiter/Saturn 1977 spacecraft is described. Electron fluences, energy spectra and dose rates obtained with this software are presented and compared with independent computer calculations.

Davis, H. S.↗
NASA NTRS1977

Radiation shielding methods

System aids in charged-particle radiation transport analysis and shielding design. System can be adapted for shielding design and analysis in any charged-particle radiation environment.

Davis, H. S.↗
NASA NTRS1982

A numerical model simulation of the regional air pollution meteorology of the greater Chesapeake Bay area - Summer day case study

The mesoscale numerical model of the University of Virginia (UVMM), has been applied to the greater Chesapeake Bay area in order to provide a detailed description of the air pollution meteorology during a typical summer day. This model provides state of the art simulations for land-sea thermally induced circulations. The model-predicted results agree favorably with available observed data. The effects of synoptic flow and sea breeze coupling on air pollution meteorological characteristics in this region, are demonstrated by a spatial and temporal presentation of various model predicted fields. A transport analysis based on predicted wind velocities indicated possible recirculation of pollutants back onto the Atlantic coast due to the sea breeze circulation.

Segal, M.↗
NASA NTRS1985

Cosmic ray environment model for Earth orbit

A set of computer codes, which include the effects of the Earth's magnetic field, used to predict the cosmic ray environment (atomic numbers 1 through 28) for a spacecraft in a near-Earth orbit is described. A simple transport analysis is used to approximate the environment at the center of a spherical shield of arbitrary thickness. The final output is in a form (a Heinrich Curve) which has immediate applications for single event upset rate predictions. The codes will culate the time average environment for an arbitrary number (fractional or whole) of circular orbits. The computer codes were run for some selected orbits and the results, which can be useful for quick estimates of single event upset rates, are given. The codes were listed in the language HPL, which is appropriate or a Hewlett Packard 9825B desk top computer. Extensive documentation of the codes is available from COSMIC, except where explanations have been deferred to references where extensive documentation can be found. Some qualitative aspects of the effects of mass and magnetic shielding are also discussed.

Edmonds, L.↗
NASA NTRS2005

Characterization of Space Shuttle Ascent Debris Aerodynamics Using CFD Methods

An automated Computational Fluid Dynamics process for determining the aerodynamic Characteristics of debris shedding from the Space Shuttle Launch Vehicle during ascent is presented. This process uses Cartesian fully-coupled, six-degree-of-freedom simulations of isolated debris pieces in a Monte Carlo fashion to produce models for the drag and crossrange behavior over a range of debris shapes and shedding scenarios. A validation of the Cartesian methods against ballistic range data for insulating foam debris shapes at flight conditions, as well as validation of the resulting models, are both contained. These models are integrated with the existing shuttle debris transport analysis software to provide an accurate and efficient engineering tool for analyzing debris sources and their potential for damage.

Murman, Scott M.↗
NASA NTRS2021

St. Joseph Peninsula Disasters: Using NASA Earth Observations to Investigate Land Cover, Shoreline Change, and Sediment Transport in St. Joseph Peninsula after Hurricane Michael

T.H. Stone Memorial St. Joseph Peninsula State Park experienced significant damages from Hurricane Michael in 2018, the first Category 5 hurricane to hit the contiguous United States since 1992. These damages included a 300-meter-wide and 10-meter-deep breach in the peninsula, habitat disruption, and a forced closure of over half of the total park area. These damages, coupled with restricted visitor access, resulted in a significant loss of revenue for the park. NASA DEVELOP partnered with the Florida Department of Environmental Protection (DEP) to determine the overall impact of Hurricane Michael on land cover and shoreline change by using NASA Earth observations including Landsat 7 Enhanced Thematic Mapper Plus (ETM+), Landsat 8 Operational Land Imager (OLI), Aqua Moderate Resolution Imaging Spectroradiometer (MODIS), and the European Space Agency’s Sentinel-2 Multispectral Instrument (MSI) to analyze sediment transport and climatology to further understand the lasting impacts of hurricanes on the ecosystems of the park. The DEVELOP team’s analyses showed that chlorophyll-a concentrations, sea surface temperature, and precipitation are increasing over time. The sediment transport analysis showed dynamic movement across the peninsula, with the greatest erosion occurring within the bay and along the length of the peninsula. These results are supported by evidence of declining seagrass abundances and seasonal turbidity patterns within those areas. Providing these analyses for the partner allows for a greater understanding of how best to proceed with restoration efforts, which may include rebuilding camping services, expanding fishing recreation, and conserving habitats for endangered species.

Erica Kriner↗
NASA NTRSDate not supplied

Particle Impact Simulation and Ignition Prediction

An experimentally calibrated tool is needed to predict if a system is susceptible to failure by particle impact ignition (PI) based on use conditions, materials, and flow geometry. This tool will accelerate new components, evaluating existing hardware, and help disposition anomalies. Conduct particle impact testing with in-situ diagnostics and complementary simulations on subset of key engineering materials (IN718, M400, 316L, 6061, Ti64, Zr) to develop a proof-of-concept predictive tool for assessing the risk of PI for idealized geometries (spherical particles) in realistic environments. Assess particle/target interactions (coefficient of restitution, ignition, kindling) using instrumented particle impact rigs while systematically varying key parameters (materials, particle size, environment, target configuration). Determine key field variables (temperature, strain, stress) in particle impacts using Multiphysics finite element and hydrocode simulations validated through comparison with experimental measurements and observations. Synthesize experiments and simulations into constitutive models for PI that can be integrated with existing computational fluid dynamics (CFD) and Debris Transport Analysis (DTA) tools in future efforts

particle impact↗
NASA NTRSDate not supplied

Synergy of Satellite Radiation, Precipitation, and Other Meteorological Variable Observations for Global Mean Sea Surface Turbulent Heat Flux Estimation

Sea surface turbulent heat flux is one of the key components in global freshwater and energy balances and plays an important role in atmospheric dynamics, thermodynamics and general circulation. This turbulent heat flux is dominantly decided by sea surface latent heat release with some contribution from sensible heat exchange. The flux and its anomaly could significantly affect ocean heat storage and ocean circulation. They are part of and have great impacts on climate variability. Though the turbulent heat flux is extremely important for the climate and weather systems, only very limited ship and buoy observations of the flux are available over open oceans. There are no global, operational, direct measurements of this crucial meteorological variable. Global estimates are, basically, indirectly calculated from bulk turbulent flux parameterization with a combination of satellite column water vapor, sea surface water temperature, and wind speed observations. Critical parameters such as sea surface air temperature and humidity are estimated from empirical relations of theses variables with the water vapor and sea surface water temperature, respectively. Lacking accurate knowledge on surface air temperature and humidity, uncertainties in the parameterization and potential changes in the non-linear turbulent processes with long-term climate variations could cause large errors in estimated long-term turbulent fluxes from the indirect method as shown in current global sea surface turbulent flux datasets. This study uses synergized data of satellite global radiation, precipitation, and other meteorological variable observations to estimate sea surface turbulent heat fluxes. The radiation observations are made by the satellite Clouds and the Earth’s Radiant Energy System (CERES) sensors, while the global precipitation data is from NASA’s satellite Global Precipitation Climatology Project (GPCP). Other data includes satellite sea surface water temperature and wind speed observations. These datasets are obtained from a wide range of space sensors from passive to active instruments and from visible and near infrared to thermal infrared and microwave spectral sounders. One significant feature of these datasets is that they have multi-decades long climate records. Top-of-atmosphere (TOA) radiation and its anomaly represents the net heat energy input to the climate system, and the oceanic precipitation and ocean-land moisture transport can be used to quantify sea surface latent heat release. Based on the synergized datasets and the principle of global water and energy balances, global mean turbulent heat fluxes are estimated. The turbulent heat anomalies for the first two decades of the 21st century are, then, obtained mainly from global CERES radiation and GPCP precipitation anomalies, along with CERES derived ocean-land heat transports. Analysis indicates that the uncertainties in the estimated turbulent flux anomalies may be reduced considerably. The results suggest a strong needs in synchronized and synergized observations of atmospheric radiation, precipitation, and oceanic meteorological variables for long-term climate studies.

Bing Lin↗
NASA NTRS2024

Particle Impact Simulation and Ignition Prediction

An experimentally calibrated tool is needed to predict if a system is susceptible to failure by particle impact ignition (PI) based on use conditions, materials, and flow geometry. This tool will accelerate new components, evaluating existing hardware, and help disposition anomalies. - Conduct particle impact testing with in-situ diagnostics and complementary simulations on subset of key engineering materials (IN718, M400, 316L, 6061, Ti64, Zr) to develop a proof-of-concept predictive tool for assessing the risk of PI for idealized geometries (spherical particles) in realistic environments. - Assess particle/target interactions (coefficient of restitution, ignition, kindling) using instrumented particle impact rigs while systematically varying key parameters (materials, particle size, environment, target configuration). - Determine key field variables (temperature, strain, stress) in particle impacts using Multiphysics finite element and hydrocode simulations validated through comparison with experimental measurements and observations. - Synthesize experiments and simulations into constitutive models for PI that can be integrated with existing computational fluid dynamics (CFD) and Debris Transport Analysis (DTA) tools in future efforts.

Jonathan Tylka↗
NASA NTRS2001

Optimizing Airspace System Capacity Through a Small Aircraft Transportation System: An Analysis of Economic and Operational Considerations

America's air transport system is currently faced with two equally important dilemmas. First, congestion and delays associated with the overburdened hub and spoke system will continue to worsen unless dramatic changes are made in the way air transportation services are provided. Second, many communities and various regions of the country have not benefited from the air transport system, which tends to focus its attention on major population centers. An emerging solution to both problems is a Small Aircraft Transportation System (SATS), which will utilize a new generation of advanced small aircraft to provide air transport services to those citizens who are poorly served by the hub and spoke system and those citizens who are not served at all. Using new innovations in navigation, communication, and propulsion technologies, these aircraft will enable users to safely and reliably access the over 5,000 general aviation landing facilities around the United States. A small aircraft transportation system holds the potential to revolutionize the way Americans travel and to greatly enhance the use of air transport as an economic development tool in rural and isolated communities across the nation.

Tarry, Scott E.↗
NASA NTRS1983

Flutter analysis of a transport wing using XTRAN3S

As part of the continuing process of evaluating and validating the XTRAN3S unsteady transonic aerodynamic computer program, the code has been applied to the flutter analysis of a transport type wing. The configuration analyzed was an aspect ratio 8 wing with a taper ratio of 0.4, a quarter chord sweep of 20 degrees and a NACA 65A-012 airfoil section. The analytical results compare well with the experimental flutter boundary and exhibit the classical 'transonic dip'. A literature search of available transport wing transonic flutter data is included.

Myers, M. R.↗
NASA NTRS1974

WAATS: A computer program for Weights Analysis of Advanced Transportation Systems

A historical weight estimating technique for advanced transportation systems is presented. The classical approach to weight estimation is discussed and sufficient data is presented to estimate weights for a large spectrum of flight vehicles including horizontal and vertical takeoff aircraft, boosters and reentry vehicles. A computer program, WAATS (Weights Analysis for Advanced Transportation Systems) embracing the techniques discussed has been written and user instructions are presented. The program was developed for use in the ODIN (Optimal Design Integration System) system.

Glatt, C. R.↗