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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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Assembly pumps liquid sodium-potassium /NaK/ eutectic at 950 K for up to 20,000 hours. Design features include - high operating-temperature capability, zero leakage, process fluid lubricant/coolant, insulation system compatible with ionizing radiation environments, and reliability and long life without maintenance.
Out-of-core nuclear thermionic converter system design feature concerning heat pipes, vapor-cooled radiators, modularity and reliability
The effect of a nonuniform electrostatic field on insulating dielectric liquids in heat pipes was studied. Topics discussed include the theory of operation, design criteria, and evaluation of optimal design features. It is concluded that the electrodynamic heat pipes offer advantages that must be weighed against the disadvantages in order to arrive at a proper assessment of their value in solving heat transfer problems.
A preliminary mechanical design of a complete lift fan engine system is reported. A description of the lift fan engine, layout drawings of the components and complete engine, and a discussion of the design analyses and results are presented. The design features and areas of analysis include fan and compressor rotor blades of composite construction, a combustor folded over the compressor, relatively high-temperature blades in the high-pressure turbine, the first stage of the low-pressure turbine used for bearing support and ducting of lubricant to the bearings, a complete lubrication system, critical speeds of the shafting, and vibration and flutter of the blading.
The design and operation of the initial modular space station are summarized. The design for a crew of six is presented and concepts for growth to twelve are discussed, including the configuration, subsystems, experiment laboratories, and flight operations. Station module designs are described and design features of the arrangements, configuration, and subsystems are discussed. A reference experiment program is presented which includes a representative phasing of experiment activity for both initial and growth stations. The flight operations required for station assembly and for carrying out the reference experiment program are also covered.
A four-bit parallel processor LSI array was designed and fabricated using COS/MOS integrated-circuit technology. The design features include the provision for interconnecting groups of parallel-processor chips to form an expanded processor of any desired word length. This 800-transistor "computer on a chip' circuit has the logic capability of a medium-size, medium-speed, general-purpose computer suitable for sophisticated scientific data processing. The ability to fabricate this device repetitively was demonstrated.
An experimental system was developed for evaluation of the effects of aerodynamic heating and cooling, vacuum, and pressure loading on candidate insulation packages proposed for use on the space shuttle. The system includes a number of design features which facilitate rapid recycle times. This is necessary to efficiently conduct extensive thermal cycling tests on these insulation packages to determine their reuse capabilities. The heart of the system is a 26-inch graphite element radiant heater. A susceptor plate functions as a uniform-temperature intermediate radiating surface. The susceptor also forms the lid of an inert atmosphere enclosure which separates the heater from the oxidizing test atmosphere. In some tests the plate properly simulates the heating from an actual flight heat-shield panel. Although other materials were used at lower required test temperatures, 2500 F was routinely achieved using a coated columbium susceptor plate.
The baseline SRM design for the space shuttle employs proven technology based on actual motor firings. Supporting research and technology are therefore required only to address system technology that is specific to the shuttle requirements, and that is needed for optimization of design features. Eight programs are recommended to meet these requirements.
Design features and characteristics of a means for measuring total temperature and total pressure at a single point in a gas stream are presented. A rake that provides five such combination measurements is described. Experimental data are included for the aerodynamic recovery and time response of the temperature sensor and for the flow-angle sensitivity of both the temperature and pressure sensors. Data were obtained over a subsonic Mach number range of 0.3 to 0.9 as well as at a Mach number of 1.4.
Fourteen C-130 airplane center wings, each containing service-imposed fatigue damage resulting from 4000 to 13,000 accumulated flight hours, were tested to determine their fatigue crack propagation and static residual strength characteristics. Eight wings were subjected to a two-step constant amplitude fatigue test prior to static testing. Cracks up to 30 inches long were generated in these tests. Residual static strengths of these wings ranged from 56 to 87 percent of limit load. The remaining six wings containing cracks up to 4 inches long were statically tested as received from field service. Residual static strengths of these wings ranged from 98 to 117 percent of limit load. Damage-tolerant structural design features such as fastener holes, stringers, doublers around door cutouts, and spanwise panel splices proved to be effective in retarding crack propagation.
A 1.83-m diameter furlable conical Gregorian antenna based on a novel spoke-supported ring-membrane concept has been successfully demonstrated. Mechanical measurements of the conical reflecting surface, as well as BE gain measurements at Ku-band, show an rms surface deviation from the proper conical surface of 0.3 mm and a repeatability after multiple furling-unfurling cycles of + or - 0.05 mm. Design features and performance characteristics of this antenna indicate that the spoke-supported ring-membrane concept is a promising approach for producing large, furlable, lightweight, conical reflectors for spacecraft high-gain antennas.
Nickel cadmium battery cells with 100 ampere hour capacity were developed. The design features, notably extension of the current collector tab to the full width of the battery plate, and the location of the cell terminals on the opposite ends, resulted in a reduction of internal impedance, and improved electrical performance with expected improvement in thermal performance. Tables of data and performance curves are included to support the theoretical considerations.
Display control considerations associated with avionics techniques are discussed. General purpose displays and a prototype interactive display/command design featuring a pushplate CRT overlay for command input are considered.
Significant progress has been made in the design, construction and operation of induction coupled devices which simulate the open cycle Gas Core Nuclear Rocket. These devices incorporate solid feed of the plasma forming material (uranium and uranium simulating materials), permeable walls, seeding of the propellant, and transpiration cooled, choked flow nozzles. Operating parameters and performance data of devices employing these design features are discussed. A uranium plasma experiment is included. In addition, operating data of several devices which compare theoretical and actual performance at a variety of powers, pressures, frequencies, and sizes are discussed.
Operational and development flight instrumentation, data handling subsystems and communication requirements of the space shuttle orbiter are discussed. Emphasis is made on data gathering methods, crew display data, computer processing, recording, and telemetry by means of a digital data bus. Also considered are overall communication conceptual system aspects and design features allowing a proper specification of telemetry encoders and instrumentation recorders. An adaptive bit rate concept is proposed to handle the telemetry bit rates which vary with the amount of operational and experimental data to be transmitted. A split-phase encoding technique is proposed for telemetry to cope with the excessive bit jitter and low bit transition density which may affect television performance.
A drag-free satellite contains a proof mass in an internal cavity and is controlled in translation so that it never touches the proof mass. The satellite shields the proof mass from external forces thus allowing the proof mass to follow a drag-free orbit. Spinning the satellite is desirable because it attenuates the effect of proof mass disturbing forces and simplifies the attitude control. The design of a translation controller for a spinning drag-free satellite typically includes a deadspace to eliminate chatter. This design feature and the inability to locate precisely the mass center give rise to a phenomenon called trapping that potentially could waste significant amounts of propellant. A theory is developed and experimentally verified that explains the role of these factors and provides insight into the effect of other control parameters.
Description of the design features and operation of a new multichannel solar spectrometer to be used for ground-based observations of active regions whose X-ray and EUV emissions are studied by the OSO-H and other satellites. The electronic systems associated with the instrument include (1) an electrooptical guider controlled by a punched paper tape capable of making raster scans of selected portions of the solar disk, (2) a programmer unit that applies paper-tape commands to various portions of the instrument, (3) a closed-loop servosystem for the vacuum heliostat, (4) stepping motor controls for spectral scans, (5) a 40-channel photomultiplier readout, and (6) a magnetometer. Preliminary solar observations indicate satisfactory performance of the system.
The device was developed to supplement the existing cooling system of the Apollo 16 Lunar Surface Magnetometer (LSM). Analysis and tests showed that two such devices, inserted by an astronaut into receptacles on opposite sides of the electronics package, would reduce the diurnal temperature variation by about 40% and thereby would considerably increase the reliability of 50,000 welded connections. The LSM design constraints, selection of a variable conductance technique, heat pipe/radiator design features, and thermal performance are discussed.