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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 397 records · Page 22

Eighth Conference on Space Simulation

The National Aeronautics and Space Administration has served as a co-sponsor of the Eighth Space Simulation Conference and has published the proceedings as a NASA Special Publication so that the information presented would be available as a permanent record and as a reference source for persons interested in the technologies. This conference provided an international forum for the discussion of the state of the art in space simulation, contamination, biosciences, and flammability. It is through this forum that many persons with differing interests and responsibilities in the aerospace research, development, and testing programs have been brought together for the interchange of knowledge in areas which affect them all. The NASA is again pleased to present, with the Institute of Environmental Sciences, American Institute of Aeronautics and Astronautics, and the American Society for Testing and Materials, this important material and to make it accessible to the greater scientific community as a NASA publication.

John H Boeckel↗

Large modular graphite radiant heaters for testing space shuttle thermal protection systems

A graphite radiant heating array, capable of heating a 5-ft span of shuttle wing leading edge or a 4 x 8 ft flat panel through an entry thermal profile up to 3200 G, has been designed and built by McDonnell Douglas Corporation for NASA-Johnson Space Center. The unique, interchangeable, self-contained heather modules and their versatile support structure/coolant manifold are discussed along with the extensive thermal analysis that accompanied the design effort. A complete description of the geometric capabilities of the array, as well as the design details of the individual modules, is presented. The complete performance envelope of the array is discussed, including maximum temperature and gradients, heating uniformity, and the required utilities and support equipment.

Cox, B. G.↗

Pressure Distribution at Subsonic Speeds over the Forepart of Two Blunt Circular Cylinders

A wind tunnel investigation was made at subsonic speeds to determine the pressure distribution over the forward part of a circular cylinder. The cylinder was equipped with interchangeable faces, one having a flat face and one having a dome shaped face. The investigation was made over angle of attack range from -1 deg to 26 deg and a Mach number range from 0.30 to 0.89. Pressure coefficients are presented in tabular form and plotted data are presented for some selected angles of attack about the surface of the cylinder.

Lockwood, V. E.↗

Experimental parametric studies of transonic T-tail flutter

Wind-tunnel tests of the T-tail of a wide-body jet airplane were made at Mach numbers up to 1.02. The model consisted of a 1/13-size scaled version of the T-tail, fuselage, and inboard wing of the airplane. Two interchangeable T-tails were tested, one with design stiffness for flutter-clearance studies and one with reduced stiffness for flutter-trend studies. Transonic antisymmetric-flutter boundaries were determined for the models with variations in: (1) fin-spar stiffness, (2) stabilizer dihedral angle (-5 deg and 0 deg), (3) wing and forward-fuselage shape, and (4) nose shape of the fin-stabilizer juncture. A transonic symmetric-flutter boundary and flutter trends were established for variations in stabilizer pitch stiffness. Photographs of the test configurations are shown.

Ruhlin, C. L.↗

AMPS definition study on Optical Band Imager and Photometer System (OBIPS)

A study was conducted to define the characteristics of a modular optical diagnostic system (OBIPS) for AMPS, to provide input to Phase B studies, and to give information useful for experiment planning and design of other instrumentation. The system described consists of visual and UV-band imagers and visual and UV-band photometers; of these the imagers are most important because of their ability to measure intensity as a function of two spatial dimensions and time with high resolution. The various subsystems of OBIPS are in themselves modular with modules having a high degree of interchangeability for versatility, economy, and redundancy.

Davis, T. N.↗

Aerodynamic results of a separation effects test on a 0.010-scale model (52-OTS) of the integrated SSV in the AEDC/VKF 40-by-40 inch supersonic wind tunnel A (IA111), volume 1

Graphical data obtained during experimental wind tunnel aerodynamic investigations of a 0.010 scale model (52-OTS) of the integrated space shuttle vehicle was presented. The purpose of this investigation was to obtain data with the solid rocket booster (SRB) in proximity to the orbiter/external tank (O/ET), over a large O/ET initial angle of attack and sideslip range, as well as data on the SRB alone (greatly separated from the O/ET). A captive trajectory system, which supported the SRB, was used with the tunnel primary sector (supporting the O/ET) to obtain grid type separation effects data. One symmetrical SRB model was used interchangeably to obtain right-hand and left-hand SRB data. The entire investigation was conducted at a free-stream Mach number of 4.5 at unit Reynolds number of 3.95 and 5.9 million per foot.

Chee, E.↗

Aerodynamic results of a separation effects test on a 0.010-scale model (52-OTS) of the integrated SSV in the AEDC/VKF 40-by-40 inch supersonic wind tunnel A (IA111), volume 2

Tabular data obtained during experimental wind tunnel aerodynamic investigations of a 0.010 scale model (52-OTS) of the integrated space shuttle vehicle was presented. The purpose of this investigation was to obtain data with the solid rocket booster (SRB) in proximity to the orbiter/external tank (O/ET), over a large O/ET initial angle of attack and sideslip range, as well as data on the SRB alone (greatly separated from the O/ET). A captive trajectory system, which supported the SRB, was used with the tunnel primary sector (supporting the O/ET) to obtain grid type separation effects data. One symmetrical SRB model was used interchangeably to obtain right-hand and left-hand SRB data. The entire investigation was conducted at free-stream Mach number of 4.5 at unit Reynolds number of 3.95 and 5.9 million per foot.

Chee, E.↗

High resolution spectrograph

The high resolution spectrograph (HRS) is designed to be used with the Large Space Telescope (LST) for the study of spectra of point and extended targets in the spectral range 110 to 410 nm. It has spectral resolutions of 1,000; 30,000; and 100,000 and has a field of view as large as 10 arc sec. The spectral range and resolution are selectable using interchangeable optical components and an echelle spectrograph is used to display a cross dispersed spectrum on the photocathode of either of 2 SEC orthicon image tubes. Provisions are included for wavelength calibration, target identification and acquisition and thermal control. The system considerations of the instrument are described.

Peacock, K.↗

Linear theory of equatorial spread F

A fluid dispersion relation for the drift and interchange (Rayleigh-Taylor) modes in a collisional plasma forms the basis for a linear theory of equatorial spread F. The collisional-drift-mode growth rate will exceed the growth rate of the Rayleigh-Taylor mode at short perpendicular wavelengths and density-gradient scale lengths. The drift mode can grow on the top-side as well as the bottom-side density gradients. It is concluded that below the F peak where spread F predominates, both the drift and Rayleigh-Taylor modes contribute to the total spread F spectrum, with the Rayleigh-Taylor mode dominating at long and the drift mode at short perpendicular wavelengths above the ion Larmor radius.

Hudson, M. K.↗

Technology of welding aluminum alloys-IV

Skate-weld carriage and track assembly were developed for controlled fusion welding on compound-curvature surfaces. Unlike fixed-position carriage used for vertical, horizontal, and circumferential welding, carriage has suspension system that permits angular positioning of weld head on carriage. It also has carriage-and-drive track mechanism capable of traveling over compound curvatures. Carriage is designed with universal mounting platform so that slim tools, weld heads, or X-ray units can be interchanged without need for realinement.

Ginez, R.↗

Lightweight Long Life Heat Exchanger

A shuttle orbiter flight configuration aluminum heat exchanger was designed, fabricated, and tested. The heat exchanger utilized aluminum clad titanium composite parting sheets for protection against parting sheet pin hole corrosion. The heat exchanger, which is fully interchangeable with the shuttle condensing heat exchanger, includes slurpers (a means for removing condensed water from the downstream face of the heat exchanger), and both the core air passes and slurpers were hydrophilic coated to enhance wettability. The test program included performance tests which demonstrated the adequacy of the design and confirmed the predicted weight savings.

Moore, E. K.↗

Advanced combined iodine dispenser and detector

A total weight of 1.23 kg (2.7 lb), a total volume of 1213 cu m (74 cu in), and an average power consumption of 5.5W was achieved in the advanced combined iodine dispenser/detector by integrating the detector with the iodine source, arranging all iodinator components within a compact package and lowering the parasitic power to the detector and electronics circuits. These achievements surpassed the design goals of 1.36 kg (3.0 lb), 1671 cu m (102 cu in) and 8W. The reliability and maintainability were improved by reducing the detector lamp power, using an interchangeable lamp concept, making the electronic circuit boards easily accessible, providing redundant water seals and improving the accessibility to the iodine accumulator for refilling. The system was designed to iodinate (to 5 ppm iodine) the fuel cell water generated during 27 seven-day orbiter missions (equivalent to 18,500 kg (40,700 lb) of water) before the unit must be recharged with iodine crystals.

Lantz, J. B.↗

An investigation of electrohydrodynamic heat pipes

The principles of electrohydrodynamic heat pip operation are first discussed. Evaporator conductance experiments are then described. A heat pipe was designed in which grooved and ungrooved evaporator surfaces could be interchanged to evaluate the necessity of capillary grooves. Optimum electrode spacing was also studied. Finally, heat convection in evaporating thin films is considered.

Loehrke, R. I.↗

NASTRAN thermal analyzer: Theory and application including a guide to modeling engineering problems, volume 2

A sample problem library containing 20 problems covering most facets of Nastran Thermal Analyzer modeling is presented. Areas discussed include radiative interchange, arbitrary nonlinear loads, transient temperature and steady-state structural plots, temperature-dependent conductivities, simulated multi-layer insulation, and constraint techniques. The use of the major control options and important DMAP alters is demonstrated.

Jackson, C. E., Jr.↗

Static and wind-on tests of an upper-surface-blown jet-flap nozzle arrangement for use on the Quiet Clean Short-haul Experimental Engine (QCSEE)

The internal aerodynamic performance, the static turning characteristics, and the forward-speed characteristics of two 1/12-scale upper surface-blown jet-flap exhaust-nozzle arrangements designed for use on the Quiet Clean Short-Haul Experimental Engine (QCSEE) were investigated. The nozzles were equipped with interchangeable area-control side doors in the aft sidewalls of the nozzle so that the effective nozzle area could be varied over a wide range. A simulated wing was used to evaluate installation losses for the nozzles. A smoothly curved flap was attached to the trailing edge of the simulated wing to allow an evaluation of the static turning characteristics of the nozzle arrangement. Forward-speed effects on the jet turning characteristics of the QCSEE nozzles were evaluated by mounting a single engine on a semispan wing designed to be representative of a four-engine STOL transport configuration.

Phelps, A. E., III↗

Study of systems and techniques for data base management

Data management areas were studied to identify pertinent problems and issues that will affect future NASA data users in terms of performance and cost. Specific topics discussed include the identifications of potential NASA data users other than those normally discussed, consideration affecting the clustering of minicomputers, low cost computer system for information retrieval and analysis, the testing of minicomputer based data base management systems, ongoing work related to the use of dedicated systems for data base management, and the problems of data interchange among a community of NASA data users.

Source record↗

Introduction: Man and his total environment

Environmental changes and the utilization of finite resources are analyzed. Beyond the satisfaction of basic physical needs, the advancement of civilization toward an ever-improving quality of like is likewise dependent upon mans' interaction with his entire environment. This larger system is controlled externally by electromagnetic and particle energy from the sun and internally by the dynamic interchange of energy between the solid earth, oceans, the atmosphere, and the magnetosphere. This exchange of energy that determines the structure of the earth's environemental system is evaluated.

Source record↗

Singularity-free extraction of a quaternion from a direction-cosine matrix

A computer algorithm for extracting a quaternion from a direction-cosine matrix (DCM) is described. The quaternion provides a four-parameter representation of rotation, as against the nine-parameter representation afforded by a DCM. Commanded attitude in space shuttle steering is conveniently computed by DCM, while actual attitude is computed most compactly as a quaternion, as is attitude error. The unit length of the rotation quaternion, and interchangeable of a quaternion and its negative, are used to advantage in the extraction algorithm. Protection of the algorithm against square root failure and division overflow are considered. Necessary and sufficient conditions for handling the rotation vector element of largest magnitude are discussed

Klumpp, A. R.↗