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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 NTRS1984

Sensor studies and space flight opportunities

Science issues, definition, instrument design studies, and hardware procurement for the multispectral atmospheric mapping sensor aircraft prototype, were all started and partially completed. The science issues for a shuttle atmospheric science experiment were defined around the precipitation processes question and results submitted and accepted for publication. Mission science objectives and payload definitions studies for the shuttle Earth observation experiment mission series were begun.

Wilson, G. S.↗

NASA NTRS1984

The International Ultraviolet Explorer (IUE): Six years in orbit

Spacecraft and scientific instrument status of the International Ultraviolet Explorer mission at 6 yr in orbit is discussed. The satellite has been in continuous operations since January 26, 1978 and continues to support science operations normally and effectively in its 7 th year of successful in-orbit operation. Sapcecraft and scientific instrument design requirements and goals are met. Design lifetime of the hardware is 3 yr with a goal, including the sizing of consumables and degradable hardware, of 5 yr.

Faelker, J.↗

NASA NTRS1983

The effects of cuing in time-shared tasks

The results of two divided-attention experiments involving the editing of route-way-point displays on an avionics computer unit are reported. Two side tasks were required of the subjects, and either no cue, verbal cues appearing on the CRT, or symbolic cues (lights on the keyboard adjacent to keys to be used) were given to facilitate the primary editing task. Forty female and 30 male undergraduates were trained in the separate and combined tasks and divided randomly into groups of 25 for the cuing tests. A second test with three 10-subject groups was conducted at least one month later to investigate the efficacy of cuing for infrequently used procedures. It is found that only symbolic cuing significantly improved primary-task performance, increasing editing accuracy in the repetitive tests and reducing editing time in the delayed tests. Verbal cuing, probably because it requires additional cognitive effort, has no significant beneficial effect. These results are considered important for designing instruments for work environments requiring the performance of concurrent tasks, and as aircraft cockpits.

Chechile, R. A.↗

NASA NTRS1984

MLA instrument concepts for future land remote sensing

The evolution of various Multispectral Linear Array (MLA) sensor concepts occurred over the past several years in response to a corresponding evolution in mission requirements. Initial efforts were concered with sensors for an Operational Land Observation System (OLOS), with free-flying spacecraft at a principal altitude of 705 km. In 1982, studies related to the definition of instruments for an Experimental Land Observation System (ELOS) were conducted. The ELOS mission involves a series of Space-Shuttle sortie flights. The ELOS MLA instrument is to perform two roles. It is to be a key tool for conducting science experiments from the Shuttle, and it is to demonstrate the technology for an eventual free-flying spacecraft. Attention is given to MLA instrument-design concepts, efforts regarding the development of sensors with many narrow spectral bands, and aspects of technology development.

Mika, A. M.↗

NASA NTRS1984

Recent trends in particle size analysis techniques

Recent advances and developments in the particle-sizing technologies are briefly reviewed in accordance with three operating principles including particle size and shape descriptions. Significant trends of the particle size analysing equipment recently developed show that compact electronic circuitry and rapid data processing systems were mainly adopted in the instrument design. Some newly developed techniques characterizing the particulate system were also introduced.

Kang, S. H.↗

NASA NTRS1985

The inference of vector magnetic fields from polarization measurements with limited spectral resolution

A method is presented for recovery of the vector magnetic field and thermodynamic parameters from polarization measurement of photospheric line profiles measured with filtergraphs. The method includes magneto-optic effects and may be utilized on data sampled at arbitrary wavelengths within the line profile. The accuracy of this method is explored through inversion of synthetic Stokes profiles subjected to varying levels of random noise, instrumental wave-length resolution, and line profile sampling. The level of error introduced by the systematic effect of profile sampling over a finite fraction of the 5 minute oscillation cycle is also investigated. The results presented here are intended to guide instrumental design and observational procedure.

Lites, B. W.↗

NASA NTRS1985

Research in extreme ultraviolet and far ultraviolet astronomy

Instruments designed to explore different aspects of far and extreme ultraviolet cosmic radiation were studied. The far ultraviolet imager (FUVI) was flown on the Aries sounding rocket. Its unique large format 75mm detector mapped out the far ultraviolet background radiation with a resolution of only a few arc minutes. Analysis of this data indicates to what extent the FUVI background is extra galactic in origin. A power spectrum of the spatial fluctuations will have direct consequences for galactic evolution.

Labov, S. E.↗

NASA NTRS1985

SAROS: Solar Active Region Observations from Spacelab

A definition study of the SAROS investigation was conducted. An instrument design and mode of operation was established which was consistent with the capabilities of the Space Transportation System. Upon completion of the definition phase study the program was placed on hold for approximately five years before being terminated. Consequently, the promise which this investigation held for understanding the heating processes in coronal loops remains unfulfilled.

Krieger, A. S.↗

NASA NTRS1986

The joint NASA/Goddard-University of Maryland research program in charged particle and high energy photon detector technology

Progress made in the following areas is discussed: low energy ion and electron experiments; instrument design for current experiments; magnetospheric measurement of particles; ion measurement in the earth plasma sheet; abundance measurement; X-ray data acquisition; high energy physics; extragalactic astronomy; compact object astrophysics; planetology; and high energy photon detector technology.

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NASA NTRS1986

A model propulsion simulator for evaluating counter rotating blade characteristics

Three Model Propulsion Simulators (MPS) were designed and built to evaluate candidate counterrotation Ultra bypass fan model blade designs of nominally 2-ft (0.61 m) tip diameter for an advanced 'pusher-type' aircraft engine. These propulsion simulators (nominally 1/5 engine size) are capable of operation over a wide range of subsonic conditions and can deliver up to 750 shaft horsepower per rotor at rotor speeds of 10,000 rpm. The rotor thrust and torque, dynamic blade stresses, and system temperature data are transmitted through an integral telemetry system to facilitate data acquisition. Salient features of the design, instrumentation, and operation of these simulators are described in this paper.

Delaney, B. R.↗

NASA NTRS1987

Computation of diffuse sky irradiance from multidirectional radiance measurements

Accurate determination of the diffuse solar spectral irradiance directly above the land surface is important in characterizing the reflectance properties of these surfaces, especially vegetation canopies. This determination is also needed to infer the net radiation budget of the earth-atmosphere system above these surfaces. An algorithm is developed here for the computation of hemispheric diffuse irradiance using the measurements from an instrument called PARABOLA, which rapidly measures upwelling and downwelling radiances in three selected wavelength bands. The validity of the algorithm is established from simulations. The standard reference data set of diffuse radiances of Dave (1978), obtained by solving the radiative transfer equation numerically for realistic atmospheric models, is used to simulate PARABOLA radiances. Hemispheric diffuse irradiance is estimated from a subset of simulated radiances by using the algorithm described. The algorithm is validated by comparing the estimated diffuse irradiance with the true diffuse irradiance of the standard data set. The validations include sensitivity studies for two wavelength bands (visible, 0.65-0.67 micron; near infrared, 0.81-0.84 micron), different atmospheric conditions, solar elevations, and surface reflectances. In most cases the hemispheric diffuse irradiance computed from simulated PARABOLA radiances and the true irradiance obtained from radiative transfer calculations agree within 1-2 percent. This technique can be applied to other sampling instruments designed to estimate hemispheric diffuse sky irradiance.

Ahmad, Suraiya P.↗

NASA NTRS1988

The Joint NASA/Goddard-University of Maryland Research Program in Charged Particle and High Energy Photon Detector Technology

Having recognized at an early stage the critical importance of maintaining detector capabilities which utilize state of the art techniques, a joint program was formulated. This program has involved coordination of a broad range of efforts and activities including joint experiments, collaboration in theoretical studies, instrument design, calibrations, and data analysis. Summaries of the progress made to date are presented. A representative bibliography is also included.

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NASA NTRS1988

Small engine components test facility turbine testing cell

NASA Lewis Research Center has designed and constructed a new state-of-the-art test facility. This facility, called the Small Engine Components Test Facility (SECTF), is used to test gas turbines and compressors at conditions similar to actual engine conditions. The SECTF is comprised of two separate facilities - a turbine test cell and a compressor test cell. The paper will describe the turbine test cell. The capabilities of the facility make it unique - no other facility of its kind is capable of combining its pressure, speed, and temperature ranges. Turbine inlet air ranges up to 9 atm (125 psig). The turbine exhaust pressure ranges from 0.15 atm (2 psia) to atmospheric pressure. Turbine inlet air temperatures range from ambient to 700 K (1260 deg R). The controllable speed of the turbine rotor ranges from 4000 to 60,000 rpm and the maximum power absorbed by the facility dynamometer is 1250 hp. The data acquisition system scans up to 2000 channels/sec. This paper will discuss in detail the capabilities of the facility, overall facility design, instrumentation used in the facility, and the data acquisition system. Actual research data is not discussed.

Nowlin, Brent C.↗

NASA NTRS1988

Infrared radiometric technique in temperature measurement

One class of commercially available imaging infrared radiometers using cooled detectors is sensitive to radiation over the 3 to 12 micron wavelength band. Spectral filters can tailor instrument sensitivity to specific regions where the target exhibits optimum radiance. The broadband spectral response coupled with real time two-dimensional imaging and emittance/background temperature corrections make the instruments useful for remote measurement of surface temperatures from -20 C to +1500 C. Commonly used radiometric techniques and assumptions are discussed, and performance specifications for a typical modern commercial instrument are presented. The potential usefulness of an imaging infrared radiometer in space laboratories is highlighted through examples of research, nondestructive evaluation, safety, and routine maintenance applications. Future improvements in instrument design and application of the radiometric technique are discussed.

Glazer, S.↗

NASA NTRS1988

Imaging spectrometer for high resolution measurements of stratospheric trace constituents in the ultraviolet

A high-resolution spectrometer has been developed for studies of minor constituents in the middle atmosphere at ultraviolet wavelengths. In particular, the instrument is intended for observations of upper stratospheric UV bands. The spectrometer has a slit width of 0.08 A obtained by means of an echelle grating and a cross-disperser grating. The image plane detector is an intensified CCD consisting of a high gain proximity focused image intensifier that is fiber optically coupled to a two-dimensional CCD array. An instantaneous bandwidth of 9.2 A is resolved across 488 pixels at 0.018 A/pixel, permitting simultaneous acquisition of multiple lines of selected OH bands and the neighboring background. The spectrometer and the approach have been successfully demonstrated as a technique for measuring the concentration of OH on two high-altitude balloon flights. This paper reports the instrument design and its achieved performance.

Torr, Marsha R.↗

NASA NTRS1988

Laminar diffusion flames under micro-gravity conditions

Laminar methane and propane gas-jet diffusion flames have been theoretically and experimentally studied at NASA-Lewis under microgravity conditions. It is noted that laminar diffusion flames are strongly affected by the combined effects of kinetics, radiation, and such transient phenomena as flame ignition, stabilization, and extinction. Observations on the distinctive nature of the flame color and luminosity parameters in microgravity are presented, and flame behavior under transient, high-deceleration rates is discussed. Test hardware and instrumentation design are described.

Edelman, Raymond B.↗

NASA NTRS1988

The Visible Airglow Experiment - A review

Contributions of the Visible Airglow Experiment (VAE) to the understanding of various airglow and auroral processes are reviewed. The impact of instrumental design and operation on the observations is discussed, and emphasis is placed on the relationship between observations and inversion for optical measurements of light emissions from a diffuse medium. VAE data are used to explain the physical mechanisms responsible for the production and destruction of excited species including O(+)(1P), O(1D), O(1S), N(2D), and Mg(+)2P1/2.

Hays, Paul B.↗

NASA NTRS1988

Small engine components test facility turbine testing cell

Nowlin, Brent C.↗