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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 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Respiratory gas exchange of high altitude adapted chick embryos

Study of gas exchange by embryos from chickens acclimatized to an altitude of 3800 m. The oxygen partial pressure and carbon dioxide partial pressure differences across the egg shell were measured and found to be less than the values previously reported for sea-level eggs by about a factor of two. Further measurements of embryonic oxygen consumption and shell conductivity to oxygen indicated that, compared to eggs at sea level, oxygen consumption was reduced by a factor of 0.58 while conductivity to oxygen was increased only by a factor of 1.07 in the high-altitude eggs. These independent measurements predict the change in oxygen partial pressure across the egg shell of the high-altitude eggs to be only 0.54 times that of sea-level eggs; the directly measured factor was 0.53. The authors conclude that at high altitude, a major adaptation of the chick embryo is a reduced metabolism which decreases the change in oxygen partial pressure across the egg shell since its gas conductivity remains essentially unchanged.

Wangensteen, O. D.↗
NASA NTRS2000

Design and Predictions for High-Altitude (Low Reynolds Number) Aerodynamic Flight Experiment

A sailplane being developed at NASA Dryden Flight Research Center will support a high-altitude flight experiment. The experiment will measure the performance parameters or an airfoil at high altitudes (70,000 - 100,000 ft), low Reynolds numbers (2 x 10(exp 5) - 7 x 10(exp 5)), and high subsonic Mach numbers (0.5 and 0.65). The airfoil section lift and drag are determined from pilot and static pressure measurements. The locations of the separation bubble, Tollmien-Schlichting boundary-layer instability frequencies, and vortex shedding are measured from a hot-film strip. The details of the planned flight experiment are presented as well as several predictions of the airfoil performance.

Greer, Donald↗
NASA NTRS1999

Design and Predictions for a High-Altitude (Low-Reynolds-Number) Aerodynamic Flight Experiment

A sailplane being developed at NASA Dryden Flight Research Center will support a high-altitude flight experiment. The experiment will measure the performance parameters of an airfoil at high altitudes (70,000 to 100,000 ft), low Reynolds numbers (200,000 to 700,000), and high subsonic Mach numbers (0.5 and 0.65). The airfoil section lift and drag are determined from pitot and static pressure measurements. The locations of the separation bubble, Tollmien-Schlichting boundary layer instability frequencies, and vortex shedding are measured from a hot-film strip. The details of the planned flight experiment are presented. Several predictions of the airfoil performance are also presented. Mark Drela from the Massachusetts Institute of Technology designed the APEX-16 airfoil, using the MSES code. Two-dimensional Navier-Stokes analyses were performed by Mahidhar Tatineni and Xiaolin Zhong from the University of California, Los Angeles, and by the authors at NASA Dryden.

Greer, Donald↗
NASA NTRSDate not supplied

High-Altitude ADS-B Flight Tests on a NASA ER-2 Research Airplane

Researchers at the National Aeronautics and Space Administration (NASA) Armstrong Flight Research Center (Edwards, California); the Federal Aviation Administration (FAA); and Regulus Group, LLC (Atlantic City, New Jersey) collaborated for the flight-test demonstration of an Automatic Dependent Surveillance-Broadcast (ADS-B) system equipped on a high-altitude Earth Resources-2 (ER-2) research airplane. The unique ER-2 airplane is a NASA-owned and operated airborne science version of the United States Air Force / Lockheed Martin Aeronautics (Bethesda, Maryland) U-2S airplane. The FAA has mandated that by the year 2020, aircraft operating within certain sections of the United States National Airspace system be equipped with ADS-B Out technology; the research presented in this paper is the first to show how the NASA ADS-B architecture satisfies the mandate for a unique high-altitude aircraft. An exceptional military aircraft design, security protocols, and the performance envelope of the ER-2 airplane made the avionics integration remarkably challenging. The design required the ADS-B avionics to survive the harsh flight environment of the ER-2 airplane. The most prominent challenge was the functional integration of modern civilian avionics into federated military legacy avionics. Flight-test objectives were to certify an ADS-B Out (1090ES) passive surveillance integrated with a Traffic Alert and Collision Avoidance System (TCAS) I active surveillance system on an ER-2 platform for high-altitude cruise operations. In April 2022, NASA conducted three flights at Edwards Air Force Base (Edwards, California) - each greater than one-hour flight reaching altitudes above 60,000 ft.

ADS-B↗
NASA NTRS1985

High-altitude plume computer code development

The flowfield codes that have been developed to predict rocket motor plumes at high altitude were used to predict plume properties for the RCS motor which show reasonable agreement with experimental data. A systematic technique was established for the calculation of high altitude plumes. The communication of data between the computer codes was standardized. It is recommended that these outlined procedures be more completed, documented and updated as the plume methodology is applied to the varied problems of plume flow and plume impingement encountered by space station design and operation.

Audeh, B. J.↗
DOE OSTI2022

The Analysis and Support for LANL Technology Testbed: High Altitude Balloon Gondola and Orion Eagle Gamma Ray Detection Instrument

The Analysis and Support for LANL Technology Testbed: High Altitude Balloon Gondola and Orion Eagle Gamma-Ray Detection Instrument is a project where Los Alamos National Laboratory (LANL), in conjunction with the University of Michigan, are looking into gamma-ray detection in a space-like environment. The purpose of the detection is to work on instruments that can assist with planetary exploration and nuclear deterrents using a High-Altitude Balloon (HAB). For this paper, the main focus is on the mechanical aspects related to the structural analysis of the gondola. It is vital to understand the structural analysis because it helps determine if the gondola can survive the changes in the environment and the different forces or shocks that it will experience when the parachute is deployed and at landing. Additionally, NASA's Balloon Program Office (BPO) has specific requirements to meet to achieve flight certifications. Part of those certifications requires the gondola to simulate different scenarios at specific conditions with various forces applied and orientations. Therefore, it is necessary to adjust the calculations of each method and the force applied to get the right results. Once that is done, the information is inputted into the structural analysis modeling system. The system will aid the mechanical team in assessing the conditions of the gondola at each scenario and determine its margin of safety. After the gondola and instrument are certified, the payload will be able to fly. The HAB and payload are launched from NASA's Columbia Scientific Balloon Facility (CSBF) at Fort Sumner, NM. The official flight was on September 26th, 2021.

42 ENGINEERING↗
NASA NTRS1973

Detection of ocean color changes from high altitudes

The detection of ocean color changes, thought to be due to chlorophyll concentrations and gelbstoffe variations, is attempted from high altitude (11.3km) and low altitude (0.3km). The atmospheric back scattering is shown to reduce contrast, but not sufficiently to obscure color change detection at high altitudes.

Hovis, W. A.↗
NASA NTRS1983

Design study for remotely piloted, high-altitude airplanes powered by microwave energy

A design study has been conducted for unmanned, microwave-powered airplanes that must fly with long endurance at high altitude. They are proposed to conduct communications-relay, observation, or various scientific missions above approximately 55,000 feet altitude. The special characteristics of the microwave-power system and high-altitude, low-speed vehicle are reviewed. Examples of both sizing and performance analysis are used to suggest design procedure guidelines.

Morris, C. E. K., Jr.↗
DOE OSTI2022

Estimation of High-Altitude Electromagnetic Pulse Signal Leakage into Power Generation Facilities: Simulations and Measurements

The coupling of early-time high-altitude electromagnetic pulse signals into a power generation facility was investigated. This study encompasses both electromagnetic simulation and on-site experimental efforts that are relevant to shielding effectiveness estimation with a passive technique. As an initial step in understanding the attenuation models involved, simulations were carried out as a function of frequency, building properties, and signal incidence angle. Testing was then performed at the US Department of Energy’s Oak Ridge National Laboratory campus to identify the equipment needed for signal collection and to fine-tune the experimental procedure. Finally, as an application of the models and methods presented, measurements were conducted at a power generation plant to derive the field transfer functions and coupled high-altitude electromagnetic pulse waveforms for various locations within the facility.

42 ENGINEERING↗
NASA NTRS1989

High altitude reconnaissance aircraft design

A Universities Space Research Association (USRA) sponsored (undergraduate) study is presented on the feasibility and design of a high altitude reconnaissance/research aircraft. The aircraft mission was to carry 1,000-3,000 lb of atmospheric pollutant monitoring equipment for 1-5 hr at an altitude of 100,000-130,000 ft. Three configurations subject to the same mission requirements were studied in detail. The three designs analyzed were the tandem-wing-twin-boom, joined wing, and conventional twin-boom configurations. The performance of the three proposed configurations is presented and shows that high altitude flight is possible with current technology. Different possible propulsion systems were investigated and suggestions are made for further investigation and better optimization of the designs.

Poladian, D.↗