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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 451 records · Page 25
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Design, fabrication, and test of a composite material wind turbine rotor blade

The aerodynamic design, structural design, fabrication, and structural testing is described for a 60 foot long filament wound, fiberglass/epoxy resin matrix wind turbine rotor blade for a 125 foot diameter, 100 kW wind energy conversion system. One blade was fabricated which met all aerodynamic shape requirements and was structurally capable of operating under all specified design conditions. The feasibility of filament winding large rotor blades was demonstrated.

Griffee, D. G., Jr.↗
NASA NTRS1978

Space Shuttle Plume Simulation Effect on Aerodynamics

Technology for simulating plumes in wind tunnel tests was not adequate to provide the required confidence in test data where plume induced aerodynamic effects might be significant. A broad research program was undertaken to correct the deficiency. Four tasks within the program are reported. Three of these tasks involve conducting experiments, related to three different aspects of the plume simulation problem: (1) base pressures; (2) lateral jet pressures; and (3) plume parameters. The fourth task involves collecting all of the base pressure test data generated during the program. Base pressures were measured on a classic cone ogive cylinder body as affected by the coaxial, high temperature exhaust plumes of a variety of solid propellant rockets. Valid data were obtained at supersonic freestream conditions but not at transonic. Pressure data related to lateral (separation) jets at M infinity = 4.5, for multiple clustered nozzles canted to the freestream and operating at high dynamic pressure ratios. All program goals were met although the model hardware was found to be large relative to the wind tunnel size so that operation was limited for some nozzle configurations.

Hair, L. M.↗
NASA NTRS1978

Design and fabrication of the Mini-Brayton Recuperator (MBR)

Development of a recuperator for a 2.0 kW closed Brayton space power system is described. The plate-fin heat exchanger is fabricated entirely from Hastelloy X and is designed for 10 years continuous operation at 1000 K (1300 F) with a Xenon-helium working fluid. Special design provisions assure uniform flow distribution, crucial for meeting 0.975 temperature effectiveness. Low-cycle fatigue, resulting from repeated startup and shutdown cycles, was identified as the most critical structural design problem. It is predicted that the unit has a minimum fatigue life of 220 cycles. This is in excess of the BIPS requirement of 100 cycles. Heat transfer performance and thermal cycle testing with air, using a prototype unit, verified that all design objectives can be met.

Killackey, J. J.↗
NASA NTRS1978

The 737 aircraft flammability testing

The FAA requested approximately 20 component and full-scale tests in a 737 fuselage to provide validation data or indicate changes that need to be made to a fire math model (Dayton Aircraft Cabin Fire Model) developed for the FAA. Some preliminary tests were conducted to evaluate the adequacy of planned instrumentation. The objectives of the program were met in that it was verified that propagation of a fire could be determined from the sequential response of thermocouples located on a test specimen(such as a seat), and continuous weighing of the specimen during the test was accomplished. Two differenct techniques for measuring smoke density were found to be comparable.

Bricker, R. W.↗
NASA NTRS1978

LACIE: An experiment in global crop forecasting

The author has identified the following significant results. Both the accuracy and efficiency with which LACIE crop survey estimates were made have shown significant improvement in three years. In the U.S. and U.S.S.R. winter wheat regions, the original accuracy goals were met or exceeded, with 90/90 estimates achieved in the United States 1.5 to 2 months before harvest. Additionally, all available accuracy parameters indicate 90/90 estimates for the U.S.S.R. total crop. Key technology problems were identified during phase 2 with spring wheat in the United States and Canada which prevented the attainment of 90/90 accuracies in these regions. Technology solutions developed and tested in phase 3 partly resolved these issues with a significant improvement realized in the accuracy of the spring wheat area estimates.

Macdonald, R. B.↗
NASA NTRS1978

Analysis and preliminary design of an optical digital tip clearance sensor for propulsion control

Following the generation of several concepts for passive, digital compatible, optical sensors for propulsion control systems, a tip clearance sensor was chosen for further analysis and preliminary design. Emphasis was placed on application to the TF34 engine compressor section. Laboratory experiments were performed to investigate several optical aspects of the concept. Preliminary design included an assessment of all sensor elements and recommendations for development programs. Quantitative predictions were made of sensor performance. A test plan was written to demonstrate sensor feasibility and that the performance goals can be met. A continuing experimental and design effort was suggested.

Poppel, G. L.↗
NASA NTRS1978

Continuous Czochralski growth: Silicon sheet growth development of the large area silicon sheet task of the Low Cost Silicon Solar Array project

The primary objective of this contract is to develop equipment and methods for the economic production of single crystal ingot material by the continuous Czochralski (CZ) process. Continuous CZ is defined for the purpose of this work as the growth of at least 100 kilograms of ingot from only one melt container. During the reporting period (October, 1977 - September, 1978), a modified grower was made fully functional and several recharge runs were performed. The largest run lasted 44 hours and over 42 kg of ingot was produced. Little, if any, degradation in efficiency was observed as a result of pulling multiple crystals from one crucible. Solar efficiencies observed were between 9.3 and 10.4% AMO (13.0 and 14.6% AMI) compared to 10.5% (14.7% AMI) for optimum CZ material control samples. Using the SAMICS/IPEG format, economic analysis of continuous CZ suggests that 1986 DoE cost goals can only be met by the growth of large diameter, large mass crystals.

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NASA NTRS1978

Large Area Crop Inventory Experiment (LACIE). Executive summary

The author has identified the following significant results. The Large Area Crop Inventory Experiment (LACIE), completed June 30, 1978, has met the USDA at-harvest goals (90% accuracy with a 90% confidence level) in the US Great Plains and U.S.S.R. for two consecutive years. In addition, in the U.S.S.R., LACIE indicated a shortfall in the '76-'77 wheat crop about two months prior to harvest, thus demonstrating the capability of LACIE to make accurate preharvest estimates.

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NASA NTRS1978

Structural Alignment Sensor Feasibility Demonstration

A structural alignment sensor (SAS) was developed for use with large deployable antenna systems for contour measurement and/or active control. The SAS is a laser ranging system using frequency modulation and accurate phase measurement to determine distance. Work was done with a CO2 and HeNe laser. The capability of the SAS to measure antenna rib contours was studied over ranges of 50 meters to a resolution of 100 microns. Initial resolution data was taken with the CO2 system. This data shows that it will indeed meet the SAS requirements. The development of the HeNe system was initiated because it offers substantial improvement in size, weight, and power over the CO2 system. The final demonstration was made with the HeNe system and it too showed that the SAS requirements could be met with this alternate approach. The projection of these results to a conceptual design for a flight system and its application are described.

Anderson, R. H.↗
NASA NTRS1979

Effects of air injection on a turbocharged Teledyne Continential Motors TSIO-360-C engine

A turbocharged fuel injected aircraft engine was operated over a range of test conditions that included that EPA five-mode emissions cycle and fuel air ratio variations for individual modes while injecting air into the exhaust gas. Air injection resulted in a decrease of hydrocarbons and carbon monoxide while exceeding the maximum recommended turbine inlet temperature of 1650 F at the full rich mixture of the engine. Leanout tests indicated that the EPA standards could be met through the combined use of fuel management and air injection.

Cosgrove, D. V.↗
NASA NTRS1979

Generalization of the Manley-Rowe relations for non-periodic signals constrained in bandwidth with finite energy

General relations for the energy spectral densities of nonperiodic signals constrained in bandwidth in nonlinear reactances are derived. It is assumed that the charge-voltage characteristics of the reactances are polynomials. In addition certain conditions for the frequency bands of the signals must be met. By contrast with the Manley-Rowe relations integrals with respect to frequency appear instead of the ratios power over frequency. The integrands are energy spectral densities divided by frequency. For parametric devices inequalities can be derived for the ratios of the energy levels in the different circuits and the limiting frequencies of the energy spectral densities. With these inequalities it is possible to determine limits for the energy levels.

Proksch, P.↗
NASA NTRS1979

Pneumatic preloaded scanning science launch latch system

A relatively simple system using a preloaded pneumatic piston latch with a pyrotechnic valve release was developed. The system was the only candidate that met all the imposed requirements utilizing reliable state-of-art components. The development of the latch system from its first use on Mariner '69 Mars Flyby Spacecraft through its most recent use on the Voyager Spacecraft that will fly to Jupiter and Saturn is reviewed.

Kievit, J. C.↗
NASA NTRS1979

Implementation Procedure for STS Payloads, System Safety Requirements

Guidelines and instructions for the implementation of the SP&R system safety requirements applicable to STS payloads are provided. The initial contact meeting with the payload organization and the subsequent safety reviews necessary to comply with the system safety requirements of the SP&R document are described. Waiver instructions are included for the cases in which a safety requirement cannot be met.

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NASA NTRS1977

DIGIMEN, optical mass memory investigations, volume 2

The DIGIMEM phase of the Optical Mass Memory Investigation Program addressed problems related to the analysis, design, and implementation of a direct digital optical recorder/reproducer. Effort was placed on developing an operational archival mass storage system to support one or more key NASA missions. The primary activity of the DIGIMEM program phase was the design, fabrication, and test and evaluation of a breadboard digital optical recorder/reproducer. Starting with technology and subsystem perfected during the HOLOMEM program phase, a fully operational optical spot recording breadboard that met or exceeded all program goals was evaluated. A thorough evaluation of several high resolution electrophotographic recording films was performed and a preliminary data base management/end user requirements survey was completed.

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NASA NTRS1979

Possible applications of space processing

Numerous applications take advantage of low gravity. These range from research, such as study of basic properties of materials or developing a better understanding of various processes and how they might be controlled, to actual production of unique materials, either in very limited quantities for research purposes to serve as paradigms for determining the limiting results of processes in which gravity effects are removed, or in large quantities, to fill certain high technology needs that cannot be met by other means. Examples of these are given in the following topics discussed: (1) crystal growth; (2) metals, alloys and composite materials (metallurgy); (3) glass and ceramics (containerless processing); (4) fluid and chemical processes; and (5) processing of biological materials.

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NASA NTRS1979

International Ultraviolet Explorer (IUE) Post Launch Report 2

The International Ultraviolet Explorer (IUE), an Explorer class ultraviolet astronomy mission, is an international cooperative program between the United States, the United Kingdom (UK), and the European Space Agency (ESA) which provides for a single launch into geosynchronous orbit to conduct spectral distribution studies of celestial and solar system ultraviolet sources. The spacecraft and scientific instruments were designed and fabricated at the Goddard Space Flight Center. The spectrograph camera was provided by the UK; ESA provided the solar array as well as the European ground station. The IUE observatory system was designed to functionally resemble a ground-based optical observatory at which guest observers could execute observing programs in real time. Observatory performance substantially exceeded design and mission objectives. The secondary mission objectives were also met.

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NASA NTRS1979

Energy efficient engine flight propulsion system preliminary analysis and design report

A flight propulsion system preliminary design was established that meets the program goals of at least a 12 percent reduction in thrust specific fuel consumption, at least a five percent reduction in direct operating cost, and one-half the performance deterioration rate of the most efficient current commercial engines. The engine provides a high probability of meeting the 1978 noise rule goal. Smoke and gaseous emissions defined by the EPA proposed standards for engines newly certified after 1 January 1981 are met with the exception of NOx, despite incorporation of all known NOx reduction technology.

Gardner, W. B.↗
NASA NTRS1978

Development of cryogenic thermal control heat pipes

The development of thermal control heat pipes that are applicable to the low temperature to cryogenic range was investigated. A previous effort demonstrated that stainless steel axially grooved tubing which met performance requirements could be fabricated. Three heat pipe designs utilizing stainless steel axially grooved tubing were fabricated and tested. One is a liquid trap diode heat pipe which conforms to the configuration and performance requirements of the Heat Pipe Experiment Package (HEPP). The HEPP is scheduled for flight aboard the Long Duration Flight Exposure Facility (LDEF). Another is a thermal switch heat pipe which is designed to permit energy transfer at the cooler of the two identical legs. The third thermal component is a hybrid variable conductance heat pipe (VCHP). The design incorporates both a conventional VCHP system and a liquid trap diode. The design, fabrication and thermal testing of these heat pipes is described. The demonstrated heat pipe behavior including start-up, forward mode transport, recovery after evaporator dry-out, diode performance and variable conductance control are discussed.

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