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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 415 records · Page 23
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Sensor performance evaluation of the Skylab multispectral photographic facility

Results of resolution tests for multispectral imagery from Skylabs 2, 3, and 4 are presented. Methods employed were visual edge matching and edge slope analysis, and resolution was evaluated as a function of spectral band, EREP pass, target orientation, field of view, exposure, and contrast. Preflight and postflight image quality data were compared. The multispectral image quality has equaled or slightly exceeded design predictions.

Corbett, F. J.↗
NASA NTRS1977

Receiver performance evaluator

Signal-to-noise ratio is estimated, and bit errors in Manchester-encoded data streams are detected, using microprocessor-based test set.

Cusack, J. A.↗
NASA NTRS1976

A performance evaluation of various coatings, substrate materials, and solar collector systems

An experimental apparatus was constructed and utilized in conjunction with both a solar simulator and actual sunlight to test and evaluate various solar panel coatings, panel designs, and scaled-down collector subsystems. Data were taken by an automatic digital data acquisition system and reduced and printed by a computer system. The solar collector test setup, data acquisition system, and data reduction and printout systems were considered to have operated very satisfactorily. Test data indicated that there is a practical or useful limit in scaling down beyond which scaled-down testing cannot produce results comparable to results of larger scale tests. Test data are presented as are schematics and pictures of test equipment and test hardware.

Dolan, F. J.↗
NASA NTRS1977

A review of the LEC performance evaluation of UHMLE

Several candidate signature extensions algorithms were evaluated. Four simulated data sets and seven consecutive day data sets were used. Analysis and evaluation of the UHMLE test and recommendations on changes in the UHMLE algorithm motivated by the test are given for each data set. The criterion for evaluation of each algorithm was overall classification accuracy.

Decell, H. P., Jr.↗
NASA NTRS1977

Performance evaluation of a quasi-microscope for planetary landers

Spatial resolutions achieved with cameras on lunar and planetary landers have been limited to about 1 mm, whereas microscopes of the type proposed for such landers could have obtained resolutions of about 1 um but were never accepted because of their complexity and weight. The quasi-microscope evaluated in this paper could provide intermediate resolutions of about 10 um with relatively simple optics that would augment a camera, such as the Viking lander camera, without imposing special design requirements on the camera of limiting its field of view of the terrain. Images of natural particulate samples taken in black and white and in color show that grain size, shape, and texture are made visible for unconsolidated materials in a 50- to 500-um size range. Such information may provide broad outlines of planetary surface mineralogy and allow inferences to be made of grain origin and evolution. The mineralogical descriptions of single grains would be aided by the reflectance spectra that could, for example, be estimated from the six-channel multispectral data of the Viking lander camera.

Burcher, E. E.↗
NASA NTRS1975

Drogue performance evaluation. Part 1: Data acquisition

Surface buoy/subsurface drogue drag coupling was investigated. Data acquisition methods and techniques derived from several experimental cruises on the Chesapeake Bay are presented. Four buoys were utilized: three coupled to steel plates rigidly attached to each other at right angles and at various depths; and one spar type that did not require drag plates. Data from these surface floats and the drogue depth combinations were processed. Errors in tracking the surface buoys are discussed.

Johnson, R. E.↗
NASA NTRS1977

Performance evaluation of electrochemical concentration cell ozonesondes

Laboratory calibrations of more than a hundred electrochemical concentration cell (ECC) ozonesondes were determined relative to UV-photometry. The average intercept and slope, 0 plus or minus 5 nb and 0.96 plus or minus 0.06, respectively, indicate reasonable agreement with UV photometry, but with considerable variation from one ECC ozonesonde to another. The time required to reach 85% of the final reaction to a step-change in ozone concentration was found to average 51 seconds. Application of the individual calibrations to 20 sets of 1976 flight data reduced the average of the differences between ozonesonde and Dobson spectrophotometric measurements of total ozone from 3.9 to 1.3%. A similar treatment of a set of 10 1977 flight records improved the average ECC-Dobson agreement from -8.5 to -1.4%. Although systematic differences were reduced, no significant effect on the random variations was evident.

Torres, A. L.↗
NASA NTRS1977

Thermal performance evaluation of Solar Energy Products Company (SEPCO) 'Soloron' collector tested outdoors

The test article, Model EF-212, Serial Nr. 002, is a single glazed collector with a nonselective absorber plate, using flowing air as the heat transfer medium. The absorber plate and box frame are aluminum and the insulation is one inch isocyanurate foam board with thermal conductivity of 0.11 (BTU/sq ft Hr0/ft.) The tests included the following. (1) time constant test, (2) collector efficiency test, (3) collector stagnation test, (4) incident angle modifier test, (5) load test, (6) weathering test, and (7) absorber plate optical properties test. The results of these tests are tabulated, graphed, or otherwise recorded.

Chiou, J., Sr.↗
NASA NTRS1977

Indoor test for thermal performance evaluation of Lenox-Honeywell solar collector

The test procedures used and the test results obtained from an evaluation test program conducted on a double-covered liquid solar collector under simulated conditions are presented. The test article was a flat plate solar collector using liquid as the heat transfer medium. The absorber plate was steel with the copper tubes bonded on the upper surface. The plate was coated with black chrome with an absorptivity factor of .95 and emissivity factor of .12. A time constant test and incident angle modifier test were conducted to determine the transient effect and the incident angle effect on the collector.

Shih, K.↗
NASA NTRS1978

Design and Performance Evaluation of Slotted Walls for Two-Dimensional Wind Tunnels

A procedure for designing slotted walls for two dimensional wind tunnels is is presented. The design objective is the minimization of blockage of streamline curvature or the reduction of both. The slotted wall boundary condition is derived both for flow from the tunnel into the plenum and vice versa, and the procedure for evaluating wall interference is described. A correlation of experimental data for the slotted wall boundary condition is given. Results are given for several designs and evaluations of slotted wind tunnel walls.

Barnwell, R. W.↗
NASA NTRS1977

Indoor test for thermal performance evaluation of Sunworks (liquid) solar collector

Test procedures used and test results obtained from an evaluation test program conducted on a single covered liquid solar collector under simulated conditions are presented. The test article was a flat plate solar collector using water as the heat transfer medium. The absorber plate was copper with copper tubes bonded by soft solder. The plate was coated with Enthone selective black with an absorptivity factor of .87 approximately .92 and an emissivity factor of .10 approximately .20. A time constant test and incident angle modifier test were conducted to determine the transient effect and the incident angle effect on the collector.

Shih, K.↗
NASA NTRS1977

Indoor thermal performance evaluation of the SEPCO air collector

The procedures used and the results obtained during the evaluation test program on the Solaron solar air collector, model EF-212, under simulated conditions for comparison with data collected in outdoor tests on the same collector are given. The test article was a single glazed collector with a nonsensitive absorber plate, aluminum box frame, and one inch isocyanurate foam insulation.

Source record↗
NASA NTRS1979

Thermal performance evaluation of MSFC hot air collectors with various flow channel depth

The test procedures used and the results obtained during the evaluation test program on the MSFC air collector with flow channel depth of 3 in., 2 in., and 1 in., under simulated conditions are presented. The MSFC hot air collector consists of a single glass cover with a nonselective coating absorber plate and uses air as the heat transfer medium. The absorber panel consists of a thin flat sheet of aluminum.

Source record↗