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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2014

NASA MSFC Electrostatic Levitator (ESL) Rapid Quench System

Electrostatic levitation, a form of containerless processing, is an important tool in materials research. Levitated specimens are free from contact with a container; therefore, heterogeneous nucleation on container walls is not possible. This allows studies of deeply undercooled melts. Furthermore, studies of high‐temperature, highly reactive materials are also possible. Studies of the solidification and crystallization of undercooled melts is vital to the understanding of microstructure development, particularly the formation of alloys with unique properties by rapid solidification. The NASA Marshall Space Flight Center (MSFC) Electrostatic Levitator (ESL) lab has recently been upgraded to allow for rapid quenching of levitated materials. The ESL Rapid Quench System uses a small crucible‐like vessel that can be partially filled with a low melting point material, such as a Gallium alloy, as a quench medium. An undercooled sample can be dropped into the vessel to rapidly quench the sample. A carousel with nine vessels sits below the bottom electrode assembly. This system allows up to nine rapid quenches before having to break vacuum and remove the vessels. This new Rapid Quench System will allow materials science studies of undercooled materials and new materials development. In this presentation, the system is described and initial results are presented.

SanSoucie, Michael P.↗
NASA NTRS2017

Controlled Nitric Oxide Production via O(1D) + N2O Reactions for Use in Oxidation Flow Reactor Studies

Oxidation flow reactors that use low-pressure mercury lamps to produce hydroxyl (OH) radicals are an emerging technique for studying the oxidative aging of organic aerosols. Here, ozone (O3) is photolyzed at 254 nm to produce O(1D) radicals, which react with water vapor to produce OH. However, the need to use parts-per-million levels of O3 hinders the ability of oxidation flow reactors to simulate NOx-dependent secondary organic aerosol (SOA) formation pathways. Simple addition of nitric oxide (NO) results in fast conversion of NOx (NO+NO2) to nitric acid (HNO3), making it impossible to sustain NOx at levels that are sufficient to compete with hydroperoxy (HO2) radicals as a sink for organic peroxy (RO2) radicals. We developed a new method that is well suited to the characterization of NOx-dependent SOA formation pathways in oxidation flow reactors. NO and NO2 are produced via the reaction O(1D)+N2O->2NO, followed by the reaction NO+O3->NO2+O2. Laboratory measurements coupled with photochemical model simulations suggest that O(1D)+N2O reactions can be used to systematically vary the relative branching ratio of RO2 +NO reactions relative to RO2 +HO2 and/or RO2+RO2 reactions over a range of conditions relevant to atmospheric SOA formation. We demonstrate proof of concept using high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) measurements with nitrate (NO-3 ) reagent ion to detect gas-phase oxidation products of isoprene and -pinene previously observed in NOx-influenced environments and in laboratory chamber experiments.

Lambe, Andrew↗
NASA NTRS2017

The Large UV/Optical/Infrared Surveyor (LUVOIR): Decadal Mission Concept Design Update

In preparation for the 2020 Astrophysics Decadal Survey, NASA has commissioned the study of four large mission concepts, including the Large Ultraviolet / Optical / Infrared (LUVOIR) Surveyor. The LUVOIR Science and Technology Definition Team (STDT) has identified a broad range of science objectives including the direct imaging and spectral characterization of habitable exoplanets around sun-like stars, the study of galaxy formation and evolution, the epoch of reionization, star and planet formation, and the remote sensing of Solar System bodies. NASA’s Goddard Space Flight Center (GSFC) is providing the design and engineering support to develop executable and feasible mission concepts that are capable of the identified science objectives. We present an update on the first of two architectures being studied: a 15-meter-diameter segmented-aperture telescope with a suite of serviceable instruments operating over a range of wavelengths between 100 nm to 2.5 microns. Four instruments are being developed for this architecture: an optical / near-infrared coronagraph capable of 10(exp -10) contrast at inner working angles as small as 2 lambda/D; the LUVOIR UV Multi-object Spectrograph (LUMOS), which will provide low- and medium-resolution UV (100 – 400 nm) multi-object imaging spectroscopy in addition to far-UV imaging; the High Definition Imager (HDI), a high-resolution wide-field-of-view NUV-Optical-IR imager; and a UV spectro-polarimeter being contributed by Centre National d’Etudes Spatiales (CNES). A fifth instrument, a multi-resolution optical-NIR spectrograph, is planned as part of a second architecture to be studied in late 2017.

Decadal Study; Astrophysics; LUVOIR↗
NASA NTRSDate not supplied

Contrails Measurement and Testing Capabilities in NASA's Particulate Aerosol Laboratory

The NASA Glenn Research Center Particulate Aerosol Laboratory (PAL) is a ground test facility for studying emissions and contrails at upper atmospheric conditions. The facility consists of a small-scale combustor that generates hot combustion gases and soot nanoparticles, which flow through a transition pipe into a jet nozzle, which exhausts into an altitude chamber. Thermodynamic conditions experienced in flight are matched in the altitude chamber, allowing the study of ice particle formation of simulated aircraft engine exhaust plumes. A non-intrusive optical diagnostic technique based on Mie scattering provides ice particle size, number density, and mass density. A suite of commercial extractive particle measurement instruments provides estimates of soot number density, size, and black carbon mass distributions. Measurements are presented for various fuels at chamber conditions covering an altitude range of 20,000 ft (6 km) to 45,000 ft (14 km) altitude and ambient temperatures from -48°C to -68°C. The data presented demonstrate the effect of soot number density, altitude, and fuel-to-air equivalence ratio on the contrail ice particle formation. Ice mass density measurements are compared to values predicted by a thermodynamic plume similarity solution.

Optical Instrumentation↗
NASA NTRS1999

Potential Climate Impacts of Engine Particle Emissions

Solid (soot) and liquid (presumed sulfate) particle emissions from aircraft engines may have serious impacts on the atmosphere. While the direct radiative impact of these particles is expected to be small relative to those from natural sources (Atmospheric Effects of Subsonic Aircraft: Interim Assessment of the Advanced Subsonic Technology Program, NASA Ref. Pub. 1400, 1997), their indirect effects on atmospheric chemistry and cloud formation may have a significant impact. The potential impacts of primary concern are the increase of sulfate surface area and accelerated heterogeneous chemical reactions, and the potential for either modified soot or sulfate particles to serve as cloud nuclei which would change the frequency or radiative characteristics of clouds. Volatile (sulfate) particle concentrations measured behind the Concorde aircraft in flight in the stratosphere were much higher than expected from near-field model calculations of particle formation and growth. Global model calculations constrained by these data calculate a greater level of stratospheric ozone depletion from the proposed High speed Civil Transport (HSCT) fleet than those without particle emission. Soot particles have also been proposed as important in heterogeneous chemistry but this remains to be substantiated. Aircraft volatile particle production in the troposphere has been shown by measurements to depend strongly on fuel sulfur content. Sulfate particles of sufficient size are known to provide a good nucleating surface for cloud growth. Although pure carbon soot is hydrophobic, the solid particle surface may incorporate more suitable nucleating sites. The non-volatile (soot) particles also tend to occupy the large end of aircraft particle size spectra. Quantitative connection between aircraft particle emissions and cloud modification has not been established yet, however, even small changes in cloud amount or properties could have a significant effect on the radiative balance of the atmosphere.

Kawa, S. Randy↗
NASA NTRS2021

Airborne and Ground-Based Measurements of Aerosol Optical Depth of Freshly Emitted Anthropogenic Plumes in the Athabasca Oil Sands Region

In this work we report the airborne aerosol optical depth (AOD) from measurements within freshly emitted anthropogenic plumes arising from mining and processing operations in the Athabasca Oil Sands Region (AOSR) in the context of ground-based AERONET climatological daily averaged AODs at Fort McMurray (Alberta, Canada). During two flights on 9 and 18 June 2018, the NASA airborne 4STAR (Spectrometers for Sky-Scanning, Sun-Tracking Atmospheric Research) Sun photometer registered high fine-mode (FM, <1 µm) in-plume AODs of up to 0.4 and 0.9, respectively, in the vicinity of the plume source (<20 km). Particle composition shows that the plumes were associated with elevated concentrations of sulfates and ammonium. These high AODs significantly exceed climatological averages for June and were not captured by the nearby AERONET instrument (mean daily AODs of 0.10±0.01 and 0.07±0.02, maximum AOD of 0.12) due possibly to horizontal inhomogeneity of the plumes, plume dilution and winds which in certain cases were carrying the plume away from the ground-based instrument. The average 4STAR out-of-plume (background) AODs deviated only marginally from AERONET daily averaged values. While 4STAR AOD peaks were generally well correlated in time with peaks in the in situ-measured particle concentrations, we show that differences in particle size are the dominant factor in determining the 4STAR-derived AOD. During the two flights of 24 June and 5 July 2018 when plumes likely travelled distances of 60 km or more, the average 4STAR FM AOD increased by 0.01–0.02 over ∼50 km of downwind particle evolution, which was supported by the increases in layer AODs calculated from the in situ extinction measurements. Based on these observations as well as the increases in organic mass, we attribute the observed AOD increase, at least in part, to secondary organic aerosol formation. The in-plume and out-of-plume AODs for this second pair of flights, in contrast to clear differences in in situ optical and other measurements, were practically indistinguishable and compared favourably to AERONET within 0.01–0.02 AOD. This means that AERONET was generally successful in capturing the background AODs, but missed some of the spatially constrained high-AOD plumes with sources as close as 30–50 km, which is important to note since the AERONET measurements are generally thought to be representative of the regional AOD loading. The fact that industrial plumes can be associated with significantly higher AODs in the vicinity of the emission sources than previously reported from AERONET can potentially have an effect on estimating the AOSR radiative impact.

AERONET↗
NASA NTRS1988

Temporal trends and transport within and around the Antarctic polar vortex during the formation of the 1987 Antarctic ozone hole

During AAOE in 1987 an ER-2 high altitude aircraft made twelve flights out of Punta Arenas, Chile (53 S, 71 W) into the Antarctic polar vortex. The aircraft was fitted with fast response instruments for in situ measurements of many trace species including O3, ClO, BrO, NO sub y, NO, H2O, and N2O. Grab samples of long-lived tracers were also taken and a scanning microwave radiometer measured temperatures above and below the aircraft. Temperature, pressure, and wind measurements were also made on the flight tracks. Most of these flights were flown to 72 S, at a constant potential temperature, followed by a dip to a lower altitude and again assuming a sometimes different potential temperature for the return leg. The potential temperature chosen was 425 K (17 to 18 km) on 12 of the flight legs, and 5 of the flight legs were flown at 450 K (18 to 19 km). The remaining 7 legs of the 12 flights were not flown on constant potential temperature surfaces. Tracer data have been analyzed for temporal trends. Data from the ascents out of Punta Arenas, the constant potential temperature flight legs, and the dips within the vortex are used to compare tracer values inside and outside the vortex, both with respect to constant potential temperature and constant N2O. The time trend during the one-month period of August 23 through September 22, 1987, shows that ozone decreased by 50 percent or more at altitudes form 15 to 19 km. This trend is evident whether analyzed with respect to constant potential temperature or constant N2O. The trend analysis for ozone outside the vortex shows no downward trend during this period. The analysis for N2O at a constant potential temperature indicates no significant trend either inside or outside the vortex; however, a decrease in N2O with an increase in latitude is evident.

Proffitt, M. H.↗
NASA NTRS1998

Space Shuttle Pinhole Formation Mechanism Studies

Pinholes have been observed to form on the wing leading edge of the space shuttle after about 10-15 flights. In this report we expand upon previous observations by Christensen (1) that these pinholes often form along cracks and are associated with a locally zinc-rich area. The zinc appears to come from weathering and peeling paint on the launch structure. Three types of experimental examinations are performed to understand this issue further: (A) Detailed microstructural examination of actual shuttle pinholes (B) Mass spectrometric studies of coupons containing, actual shuttle pinholes and (C) Laboratory furnace studies of ZnO/SiC reactions and ZnO/SiC protected carbon/carbon reaction. On basis of these observations we present a detailed mechanism of pinhole formation due to formation of a corrosive ZnO-Na-2-O-SiO2 ternary glass, which flows into existing cracks and enlarges them.

Jacobson, Nathan S.↗
NASA NTRS1999

Osteoblast fibronectin mRNA, protein synthesis, and matrix are unchanged after exposure to microgravity

The well-defined osteoblast line, MC3T3-E1 was used to examine fibronectin (FN) mRNA levels, protein synthesis, and extracellular FN matrix accumulation after growth activation in spaceflight. These osteoblasts produce FN extracellular matrix (ECM) known to regulate adhesion, differentiation, and function in adherent cells. Changes in bone ECM and osteoblast cell shape occur in spaceflight. To determine whether altered FN matrix is a factor in causing these changes in spaceflight, quiescent osteoblasts were launched into microgravity and were then sera activated with and without a 1-gravity field. Synthesis of FN mRNA, protein, and matrix were measured after activation in microgravity. FN mRNA synthesis is significantly reduced in microgravity (0-G) when compared to ground (GR) osteoblasts flown in a centrifuge simulating earth's gravity (1-G) field 2.5 h after activation. However, 27.5 h after activation there were no significant differences in mRNA synthesis. A small but significant reduction of FN protein was found in the 0-G samples 2.5 h after activation. Total FN protein 27.5 h after activation showed no significant difference between any of the gravity conditions, however, there was a fourfold increase in absolute amount of protein synthesized during the incubation. Using immunofluorescence, we found no significant differences in the amount or in the orientation of the FN matrix after 27.5 h in microgravity. These results demonstrate that FN is made by sera-activated osteoblasts even during exposure to microgravity. These data also suggest that after a total period of 43 h of spaceflight FN transcription, translation, or altered matrix assembly is not responsible for the altered cell shape or altered matrix formation of osteoblasts.

Flight Experiment↗
NASA NTRS1979

Application of a coupled aerosol formation: Radiative transfer model to climatic studies of aerosols

A sophisticated one dimensional physical-chemical model of the formation and evolution of stratospheric aerosols was used to predict the size and number concentration of the stratospheric aerosols as functions of time and altitude following: a large volcanic eruption; increased addition of carbonyl sulfide (OCS) or sulfur dioxide (SO2) to the troposphere; increased supersonic aircraft (SST) flights in the stratosphere; and, large numbers of space shuttle (SS) flights through the stratosphere. A radiative-convective one dimensional climate sensitivity study, using the results of the aerosol formation model, was performed to assess the ground level climatic significance of these perturbations to the stratospheric aerosol layer. Volcanic eruptions and large OCS or SO2 increases could cause significant climatic changes. Currently projected SS launches and moderate fleets of SST's are unlikely to upset the stratospheric aerosol layer enough to significantly impact climate.

Toon, O. B.↗
NASA NTRS1993

Cockpit checklists - Concepts, design, and use

Although the aircraft checklist has long been regarded as a foundation of pilot standardization and cockpit safety, it has escaped the scrutiny of the human factors profession. The improper use, or nonuse, of the normal checklist by flight crews is often cited as a major contributing factor to aircraft accidents. This paper reports the results of a field study of flight deck checklists and examines this seemingly mundane yet critical device from several perspectives: its functions, format, design, length, and usage, and the limitations of the humans who must interact with it. Certain sociotechnical factors, such as the airline 'culture', cockpit resource management, and production pressures that influence the design and use of this device, are also discussed. Finally, a list of design guidelines for normal checklists is provided. Although the focus of this paper is on the air transport industry, most of the principles discussed apply equally well to other high-risk industries, such as maritime transportation, power production, weapons systems, space flight, and medical care.

Degani, Asaf↗
NASA NTRSDate not supplied

Zero-G Experiments of the BionicWingsat - A 2U-Cubesat with Deployable, Biologically-Inspired Wings

In this paper, recent testing of a novel deployable structure with several potential applications in space will be described, with the focus on performed deployment experiments in a DLR Zero-g flight campaign and in ground tests. Through a cooperative effort of the German Aerospace Center (DLR) and the National Aeronautics and Space Administration (NASA), a biologically-inspired structurally-integrated membrane featuring distributed functional elements has been developed and integrated into the 2U CubeSat called BionicWingSat. Such a membrane structure could be useful for all sorts of applications in which a relatively flat area is desirable such as solar sails, drag sails, or solar shades. For SmallSats and CubeSats, the design proposed also has the desirable property of being self-deploying without the need for powered deployment mechanisms. Building on previous work inspired by the wings of earwigs, the research presented in this paper focuses on testing of developed design concepts for such structural systems. To do so 24 fully integrated wings on two BionicWingSats in 2U Cubesat format were experimentally deployed in a microgravity environment during a dedicated DLR Zero-g flight campaign in 2021. The results of these experiments, the built hardware and test articles, the test arrangement, as well as a comparison to ground tests are discussed in this paper.

Spacecraft structures↗
NASA NTRS2010

Sustaining Human Space Flight: From the Present to the Future

This slide presentation reviews some of the efforts to ensure that human space flight continues in NASA. With the aging shuttle orbiter fleet, some actions have been taken to assure safe operations. Some of these are: (1) the formation of a Corrosion Control Review Board (CCRB) that will assess the extent and cause of corrosion to the shuttle, and provide short term and long term corrective actions, among other objectives, (2) a formalization of an aging vehicle assessment (AVA) as part of a certification for the Return-to-Flight, (3) an assessment of the age life of the materials in the space shuttle, and (4) the formation of the Aging Orbiter Working Group (AOWG). There are also slides with information about the International Space Station. There is also information about the need to update the Kennedy Space Center, to sustain a 21st century launch complex and the requirement to further the aim of commercial launch capability.

Russell, Rick↗
NASA NTRS1999

Avian Blood-Vessel Formation in Space

Based on previous studies, we hypothesized that the developmental anomalies observed in the past might be related to or caused by delayed or improper vascular development. The objective of our research is to test the hypothesis that exposure to microgravity during space flight cause delayed or improper vascular development during embryogenesis. The effects of microgravity on the time course and extent of avian blood-vessel formation are assessed using two models, one for angiogenesis and one for vasculogenesis. The methodological approach is dictated by the constraints of the tissue preservation method used in space. Thus, both in the chorioallantoic membrane (CAM) and in the adrenal, we will evaluate microscopically the vascular architecture and immunostain endothelial cells with specific antibodies (anti- vWF and QH1). The extent of ECM protein deposition will be assessed by immunohistochemistry and correlated with the degree of vascularization, using computer-based image analysis. Also, the cellular source for ECM proteins will be assessed by in situ hybridization.

Lelkes, Peter I.↗
NASA NTRS1984

A 0.15-scale study of configuration effects on the aerodynamic interaction between main rotor and fuselage

Hover and forward flight tests were conducted to investigate the mutual aerodynamic interaction between the main motor and fuselage of a conventional helicopter configuration. A 0.15-scale Model 222 two-bladed teetering rotor was combined with a 0.15-scale model of the NASA Ames 40x80-foot wind tunnel 1500 horsepower test stand fairing. Configuration effects were studied by modifying the fairing to simulate a typical helicopter forebody. Separation distance between rotor and body were also investigated. Rotor and fuselage force and moment as well as pressure data are presented in graphical and tabular format. Data was taken over a range of thrust coefficients from 0.002 to 0.007. In forward flight speed ratio was varied from 0.1 to 0.3 with shaft angle varying from +4 to -12 deg. The data show that the rotors effect on the fuselage may be considerably more important to total aircraft performance than the effect of the fuselage on the rotor.

Trept, Ted↗
NASA NTRS2002

Console Log Keeping Made Easier - Tools and Techniques for Improving Quality of Flight Controller Activity Logs

At the Marshall Space Flight Center's (MSFC) Payload Operations Integration Center (POIC) for International Space Station (ISS), each flight controller maintains detailed logs of activities and communications at their console position. These logs are critical for accurately controlling flight in real-time as well as providing a historical record and troubleshooting tool. This paper describes logging methods and electronic formats used at the POIC and provides food for thought on their strengths and limitations, plus proposes some innovative extensions. It also describes an inexpensive PC-based scheme for capturing and/or transcribing audio clips from communications consoles. Flight control activity (e.g. interpreting computer displays, entering data/issuing electronic commands, and communicating with others) can become extremely intense. It's essential to document it well, but the effort to do so may conflict with actual activity. This can be more than just annoying, as what's in the logs (or just as importantly not in them) often feeds back directly into the quality of future operations, whether short-term or long-term. In earlier programs, such as Spacelab, log keeping was done on paper, often using position-specific shorthand, and the other reader was at the mercy of the writer's penmanship. Today, user-friendly software solves the legibility problem and can automate date/time entry, but some content may take longer to finish due to individual typing speed and less use of symbols. File layout can be used to great advantage in making types of information easy to find, and creating searchable master logs for a given position is very easy and a real lifesaver in reconstructing events or researching a given topic. We'll examine log formats from several console position, and the types of information that are included and (just as importantly) excluded. We'll also look at when a summary or synopsis is effective, and when extensive detail is needed.

Scott, David W.↗
NASA NTRS2005

Advanced Pathway Guidance Evaluations on a Synthetic Vision Head-Up Display

NASA's Synthetic Vision Systems (SVS) project is developing technologies with practical applications to potentially eliminate low visibility conditions as a causal factor to civil aircraft accidents while replicating the operational benefits of clear day flight operations, regardless of the actual outside visibility condition. A major thrust of the SVS project involves the development/demonstration of affordable, certifiable display configurations that provide intuitive out-the-window terrain and obstacle information with advanced guidance for commercial and business aircraft. This experiment evaluated the influence of different pathway and guidance display concepts upon pilot situation awareness (SA), mental workload, and flight path tracking performance for Synthetic Vision display concepts using a Head-Up Display (HUD). Two pathway formats (dynamic and minimal tunnel presentations) were evaluated against a baseline condition (no tunnel) during simulated instrument meteorological conditions approaches to Reno-Tahoe International airport. Two guidance cues (tadpole, follow-me aircraft) were also evaluated to assess their influence. Results indicated that the presence of a tunnel on an SVS HUD had no effect on flight path performance but that it did have significant effects on pilot SA and mental workload. The dynamic tunnel concept with the follow-me aircraft guidance symbol produced the lowest workload and provided the highest SA among the tunnel concepts evaluated.

Kramer, Lynda J.↗
NASA NTRS2006

Demonstration of an Ice Contamination Effects Flight Training Device

The development of a piloted flight simulator called the Ice Contamination Effects Flight Training Device (ICEFTD) was recently completed. This device demonstrates the ability to accurately represent an iced airplane s flight characteristics and is utilized to train pilots in recognizing and recovering from aircraft handling anomalies that result from airframe ice formations. The ICEFTD was demonstrated at three recent short courses hosted by the University of Tennessee Space Institute. It was also demonstrated to a group of pilots at the National Test Pilot School. In total, eighty-four pilots and flight test engineers from industry and the regulatory community spent approximately one hour each in the ICEFTD to get a "hands on" lesson of an iced airplane s reduced performance and handling qualities. Additionally, pilot cues of impending upsets and recovery techniques were demonstrated. The purpose of this training was to help pilots understand how ice contamination affects aircraft handling so they may apply that knowledge to the operations of other aircraft undergoing testing and development. Participant feedback on the ICEFTD was very positive. Pilots stated that the simulation was very valuable, applicable to their occupations, and provided a safe way to explore the flight envelope. Feedback collected at each demonstration was also helpful to define additional improvements to the ICEFTD; many of which were then implemented in subsequent demonstrations

Ratvasky, Thomas P.↗