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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 NTRS1976

Survey of inlet noise reduction concepts for gas turbine engines

An overview is given of advanced concepts for the suppression of noise in the inlets of gas turbine engines. Inlet geometric and operating parameters are presented and design criteria for suppression methods are discussed. Noise suppression concepts are described, the directions of current research are reviewed. Problem areas requiring further work are indicated. Well established approaches to inlet noise reduction - namely, acoustic liners and high subsonic Mach number inlets which are the focus of considerable current research activity are considered along with the acoustic absorption and watet vapor injection.

Lansing, D. L.↗
NASA NTRS1976

Rotary mechanism for wind tunnel stall/spin studies

The critical problem of stall-spin characteristics of high performance aircraft and the need for experimental data in this area are reviewed. A rotary mechanism for obtaining this aerodynamic data in a conventional wind tunnel is presented. The intricacies of the drive systems and the articulation available through such a mechanism are described.

Mancini, R. E.↗
NASA NTRS1977

Oblique wing transonic transport configuration development

Studies of transport aircraft designed for boom-free supersonic flight show the variable sweep oblique wing to be the most efficient configuration for flight at low supersonic speeds. Use of this concept leads to a configuration that is lighter, quieter, and more fuel efficient than symmetric aircraft designed for the same mission. Aerodynamic structural, weight, aeroelastic and flight control studies show the oblique wing concept to be technically feasible. Investigations are reported for wing planform and thickness, pivot design and weight estimation, engine cycle (bypass ratio), and climb, descent and reserve fuel. Results are incorporated into a final configuration. Performance, weight, and balance characteristics are evaluated. Flight control requirements are reviewed, and areas in which further research is needed are identified.

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NASA NTRS1978

Automated Mixed Traffic Vehicle (AMTV) technology and safety study

Technology and safety related to the implementation of an Automated Mixed Traffic Vehicle (AMTV) system are discussed. System concepts and technology status were reviewed and areas where further development is needed are identified. Failure and hazard modes were also analyzed and methods for prevention were suggested. The results presented are intended as a guide for further efforts in AMTV system design and technology development for both near term and long term applications. The AMTV systems discussed include a low speed system, and a hybrid system consisting of low speed sections and high speed sections operating in a semi-guideway. The safety analysis identified hazards that may arise in a properly functioning AMTV system, as well as hardware failure modes. Safety related failure modes were emphasized. A risk assessment was performed in order to create a priority order and significant hazards and failure modes were summarized. Corrective measures were proposed for each hazard.

Johnston, A. R.↗
NASA NTRS1978

Applications of Geodesy to Geodynamics, an International Symposium

Geodetic techniques in detecting and monitoring geodynamic phenomena are reviewed. Specific areas covered include: rotation of the earth and polar motion; tectonic plate movements and crustal deformations (space techniques); horizontal crustal movements (terrestrial techniques); vertical crustal movements (terrestrial techniques); gravity field, geoid, and ocean surface by space techniques; surface gravity and new techniques for the geophysical interpretation of gravity and geoid undulation; and earth tides and geodesy.

Mueller, I. I.↗
NASA NTRS1978

The NASA space power technology program

The objective and planning of the NASA space power research and technology program are reviewed. The areas of research covered include photovoltaic energy conversion, chemical energy conversion and storage, thermal to electric conversion, environmental interactions and power systems management of distribution.

Mullin, J. P.↗
NASA NTRS1980

Instrument development for a toxic level hypergolic vapor detector

The development and deployment of technology applicable to the field measurement of hypergolic propellants is discussed. The propellants include hydrazine (H) monomethylhydrazine (MMH), and 1,1-dimethylhydrazine (UDMH) at the parts per billion (PPB) level in air or a diluent gas. Four major areas are reviewed: (1) development of an improved electrochemical sensor for the measurement of hydrazines (H, MMH and UDMH) in air; (2) prototype instrument fabrication and subsequent laboratory evaluation; (3) initial instrument field test results; and (4) future requirements and applications.

Rogers, P. M.↗
NASA NTRS1981

Recent progress towards predicting aircraft ground handling performance

Capability implemented in simulating aircraft ground handling performance is reviewed and areas for further expansion and improvement are identified. Problems associated with providing necessary simulator input data for adequate modeling of aircraft tire/runway friction behavior are discussed and efforts to improve tire/runway friction definition, and simulator fidelity are described. Aircraft braking performance data obtained on several wet runway surfaces are compared to ground vehicle friction measurements. Research to improve methods of predicting tire friction performance are discussed.

Yager, T. J.↗
NASA NTRS1978

Solar Terrestrial programs: A five year plan

Major projects to be initiated in the 1980-1985 period, designed to study the Sun, the heliosphere, Earth's magnetosphere, and the upper atmosphere involve the use of spacelab as well as free flying spacecraft. Current and recent investigations in these areas are reviewed and the guiding principles followed in planning future missions are examined. The implementation strategy, the planning process, and supporting research and technology are discussed.

Stern, D. P.↗
NASA NTRS1981

Biomedical research

Biomedical problems encountered by man in space which have been identified as a result of previous experience in simulated or actual spaceflight include cardiovascular deconditioning, motion sickness, bone loss, muscle atrophy, red cell alterations, fluid and electrolyte loss, radiation effects, radiation protection, behavior, and performance. The investigations and the findings in each of these areas were reviewed. A description of how biomedical research is organized within NASA, how it is funded, and how it is being reoriented to meet the needs of future manned space missions is also provided.

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NASA NTRS1981

The spontaneous concentration of magnetic field in the photosphere of the sun

The basic physics of magnetic flux tubes in the solar photosphere is reviewed, with areas still open to conjecture pointed out. The question of the concentration of individual small flux tubes to levels of 1-2 kilogauss, when the average solar surface magnetic field is on the order of 10 gauss, by processes of twisting and the formation of flux ropes made up of tubes wound around each other is considered together with the effects of turbulence on the flux tube. Mechanisms for tube compression by the evacuation of the gas contained within a flux tube are then examined, and the possibility of field concentration through the cooling of the gas within the tube in a superadiabatic process is suggested. Attention is then given to possible mechanisms serving to maintain the concentration of flux tubes far below the surface of the sun which gives rise to sunspots and pores as the flux tree emerges through the surface.

Parker, E. N.↗
NASA NTRS1981

Remote sensing in the coastal zone: A perspective

The problems involved in satellite remote sensing of coastal zones are examined. The differences between remote sensing of terrestrial regions and remote sensing of open ocean areas are reviewed. The associate ranges of time and spatial scales and spectral and radiometric resolution are considered. It is concluded that, in general remote sensing of the coastal region is more appropriately performed with aircraft.

Cornillon, P.↗
NASA NTRS1983

Report of the infrared, ultraviolet and space plasma panels

The status of the payload bay and the needs of infrared, ultraviolet and space plasma experiments were discussed. Those measurements important in each area were reviewed. Issues of concern and how these environmental conditions might impact experiments were considered. Several common issues were revealed, and recommendations were made.

Lehmann, J.↗
NASA NTRS1982

X-rays from quasars and active galaxies

Some of the most important theoretical ideas and observations for quasars and the nuclei of active galaxies are reviewed, and areas of future research are suggested. Emphasis is on the nature of the power source, the radiation processes, and the mechanism for formation and collimation of jets. Phenomena that produce X-rays are of particular concern. Particular topics discussed are the observed and expected time variabilility, the gas supply mechanisms and luminosity evolution, thermal and nonthermal radiation processes, observed and theoretical spectra, criteria for thermalization of electrons and ions, effects of electron-positron pairs on relativistic plasmas, hydrodynamic, electrodynamic and inertial methods for producing and confining jets. The paper concludes with a list of needed observations.

Lightman, A. P.↗
NASA NTRS1983

Research on the adaptation of skeletal muscle to hypogravity Past and future directions

The results of previous research on the cellular effects of microgravity on rat tissue are reviewed and areas of future necessary research are identified. The rats were flown on board Cosmos 605, 782, and 936. Postflight tissue analyses revealed increases in connective tissue cells and focal disruption of muscle fibers due to the microgravity environment of space. Evidence has been found for muscular and neural changes occurring as a result of reentry stresses. It is suggested that a data base be established for quantizing muscle function with electromyography, measurements of force output, and length measurement. The data can serve as a reference for comparisons with data obtained in orbiting laboratories such as the Spacelab. The experiments will have a goal of defining and preventing the mechanism of neuromuscular atrophy.

Riley, D. A.↗
NASA NTRS1983

Hot plasma composition results from the ISEE-1 spacecraft

The International Sun Earth Explorer (ISEE-1) was launched on Oct. 22, 1977 into a geocentric elliptical orbit. The energetic ion mass spectrometer on the satellite is employed in a study of the plasmas encountered by ISEE-1 in its orbits. The experiment is operating successfully and research is progressing in a number of areas. A review in the nature of a progress report on the energetic magnetospheric plasma results is provided. Attention is given to the plasma sheet and ion streams in the magnetotail, the inner magnetosphere, and magnetospheric boundary regions.

Sharp, R. D.↗
NASA NTRS1982

Botanical sciences team

Improvements in vegetation monitoring and mapping which would result from increased spectral and spatial resolution in multispectral systems are discussed. Current knowledge of the spectral properties of vegetation is reviewed and areas where existing knowledge is incomplete are identified. In addition, the effects of the atmosphere on the remote sensing of vegetation are examined.

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NASA NTRS1985

A modeling analysis program for the JPL table mountain Io sodium cloud

Progress and achievements in the first year are discussed in three main areas: (1) review and assessment of the massive JPL Table Mountain Io sodium cloud data set, (2) formulation and execution of a plan to perform further processing of this data set, and (3) initiation of modeling activities. The complete 1976-79 and 1981 data sets are reviewed. Particular emphasis is placed on the superior 1981 Region B/C images which provide a rich base of information for studying the structure and escape of gases from Io as well as possible east-west and magnetic longitudinal asymmetries in the plasma torus. A data processing plan is developed and is undertaken by the Multimission Image Processing Laboratory of JPL for the purpose of providing a more refined and complete data set for our modeling studies in the second year. Modeling priorities are formulated and initial progress in achieving these goals is reported.

Smyth, W. H.↗