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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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Potential applications of the proposed space station are briefly examined. Areas considered include communications (bulk traffic, direct broadcast, and assembly of GEO platforms), earth sciences (repair and refurbishment of long-term spacecraft), and materials processing. The importance of developing a comfortable habitat is stressed.
The systems engineering aspects of developing a conceptual design of the Space Station Environmental Control and Life Support System (ECLSS) are discussed. Topics covered include defining system requirements and groundrules for approach, formulating possible cycle closure options, and establishing a system-level mass balance on the essential materials processed in oxygen and water cycles. Consideration is also given to the performance of a system trade-off study to determine the best degree of cycle closure for the ECLSS, and the construction of a conceptual design of the ECLSS with subsystem performance specifications and candidate concepts. For the optimum balance between development costs, technological risks, and resupply penalties, a partially closed cycle ECLSS option is suggested.
A finite amplitude sound wave can exert a radiation force on an object due to second-order effect of the wave field. The radiation force on a rigid small sphere (i.e., in the long wavelength limit), which has a temperature different from that of the environment, is presently studied. This investigation assumes no thermally induced convection and is relevant to material processing in the absence of gravity. Both isotropic and nonisotropic temperature profiles are considered. In this calculation, the acoustic effect and heat transfer process are essentially decoupled because of the long wavelength limit. The heat transfer information required for determining the force is contained in the parameters, which are integrals over the temperature distribution.
High spatial resolution infrared maps of the core of the evolved planetary nebula Abell 30, which has been shown to be composed of heavily processed material, are presented. These maps reveal an elongated, disklike structure that is not evident on optical pictures. Multicolor photometry at several positions in this disk shows that this emission is due to dust, some of which is near the evaporation temperature of graphite. Lyman-alpha trapping is shown to be inadequate as a heating source for these grains, but direct absorption of stellar photons is sufficient. In view of the unusual chemical composition, A30 represents a late stage in the evolution of a planetary nebula progenitor. The observed infrared structure may provide clues to the ejection mechanism at this stage of development.
The policy, legal, and economic aspects of space industrialization are considered along with satellite communications, material processing, remote sensing, and the role of space carriers and a space station in space industrialization.
Materials processing in space utilizing the microgravity environment is discussed; glass processing in particular is considered. Attention is given to the processing of glass shells, critical cooling rate and novel glasses, gel synthesis of glasses, immiscibility, surface tension, and glass composites. Soviet glass experiments in space are also enumerated.
The use of the F-104 Interceptor for low gravity materials processing experiments is extended to include alloy solidification studies above 1000 C. The F-104 can provide up to 60 seconds of low gravity, but requires a unique experiment package for integration into the aircraft, both physically and electronically. The current research with the F-104 experimental furnace system which has been used to process cast iron samples is described. Results demonstrate the capability of the facility and its operation.
Recent developments of the General Electric hybrid rotor design are described. The relation of the hybrid rotor design to flywheel designs that are especially suitable for spacecraft applications is discussed. Potential performance gains that can be achieved in such rotor designs by applying latest developments in materials, processing, and design methodology are projected. Indications are that substantial improvements can be obtained.
Conceived as one or more arrays of carriers which would fly aboard space shuttle, Commerce Lab can provide a point of focus for implementing a series of shuttle flights, co-sponsored by NASA and U.S. domestic concerns, for performing materials processing in research and pre-commercial investigations. As an orbiting facility for testing, developing, and implementing hardware and procedures, Commerce Lab can enhance space station development and hasten space platform production capability. Tasks considered include: (1) synthesis of user requirements and identification of common element and voids; (2) definition of performance and infrastructure requirement and alternative approaches; and (3) carrier, mission model, and infrastructure development.
A low gravity exothermic heating/cooling apparatus is disclosed for processing materials in space which includes an insulated casing and a sample support carried within the casing which support a sample container. An exothermic heat source includes a plurality of segments of exothermic material stacked one upon another to produce a desired temperature profile when ignited. The sample container is arranged within the core of the stacked exothermic heating material. Igniters are spaced vertically along the axis of the heating material to ignite the exothermic material at spaced points to provide total rapid burn and release of heat. To rapidly cool and quench the heat, a source of liquid carbon dixoide is provided which is conveyed through a conduit and a metering orifice into a distribution manifold where the carbon dioxide is gasified and dispersed around the exothermic heating material and the sample container via tubes for rapidly cooling the material sample.
Progress made by the Flat-Plate Solar Array Project is described. Reports on silicon sheet growth and characterization, silicon material, process development, high-efficiency cells, environmental isolation, engineering sciences, and reliability physics are presented along with copies of visual presentations made at the 24th Project Integration Meeting.
Spectrophotometric observations of emission-line intensities over the spectral range 1400 to 7200 A were made in five positions in the planetary nebula NGC 7662. Standard equations used to correct for the existence of elements in other than the optically observable ionization stages show a consistent and approximate agreement with abundances calculated using ultraviolet lines. The abundances of C and N indicate that some mixing of CNO-processed material into the nebular shell may have occurred in NGC 7662; the low He abundance, however, indicates that little or no He enrichment occurred. The Ar, Ne, and O and S abundances appear to be low. It is suggested that the progenitor to NGC 7662 may have formed out of somewhat metal-poor material.
Upgraded UV and IR data were taken of the planetary nebula NGC 6853 in the same region as previous optical data to improve the data base on various ionized species in the nebula. The spectral range 1400-9600 A was scanned, and good agreement was obtained between UV and optical ionization abundance data, although the 4267 A C II line yielded a C(2+) abundance larger than indicated by the UV data. The discrepancy concentrated around the central star. Ionization abundances were determined for He, O, N, NC, C, Ar, and S relative to H, and the causes of discrepancies in the abundances compared to those of previous investigators are discussed. It is noted that, as in the planetary nebula NGC 6720, lighter element abundances are higher than solar values, which suggests mixing of processed materials in the envelope of the two nebulae.
The paper investigates the photodissociation of CO in interstellar clouds in the light of recent laboratory studies which suggest that line rather than continuum processes dominate its dissociation by ultraviolet radiation. Using a simple radiative transfer model, the shielding of representative dissociating bands is estimated, including self-shielding, mutual shielding between different isotopes, and near coincidences with strong lines of H2. Each of these processes materially affects the photodestruction rates of the various isotopic species in the transition regions of molecular clouds. These results are combined with an appropriate gas phase chemical model to determine how the abundances of the CO isotopes vary with depth into the cloud. It is found that self-shielding and mutual shielding cause significant variations in isotopic ratios. In addition, fractionation enhances species containing C-13. The relationship between the column densities of CO and H2 is found to vary for the different isotopes and to be sensitive to local conditions.
Space Shuttle missions are currently limited to 11 days, primarily due to depletion of the power reactants (hydrogen and oxygen). A power system Mission Extension Kit (MEK) is described which could provide the capability to stay on orbit 10 additional days. These extra days would benefit Space Station construction and missions such as materials processing, earth and celestial observation, and life science studies (Spacelab). Other constraints to longer missions which may dictate minor Orbiter modifications will be discussed. The power system MEK is particularly desirable because of its existing flight qualified hardware which can be delivered within 3 to 4 years.
In the course of the unmanned exploration of the solar system, which the California Institute of Technology's Jet Propulsion Laboratory has managed for NASA, major advances in computerized image processing, materials research, and miniature electronics design have been accomplished. This presentation shows some of the imaging results from space exploration missions, as well as biomedical research tasks based in these technologies. Among other topics, the use of polymeric microspheres in cancer therapy is discussed. Also included are ceramic applications to prosthesis development, laser applications in the treatment of coronary artery disease, multispectral imaging as used in the diagnosis of thermal burn injury, and some examples of telemetry systems as they can be involved in biological systems.
The role of automation and robotics in support of man's activities in space is discussed, with emphasis given to satellite servicing functions on board the NASA Space Station (SS) or at remote locations. Consideration is given to four satellite servicing mission scenarios, including: low-earth-orbit (LEO) servicing of satellite in situ or on the Space Station following orbital transfer by means of an Orbital Maneuvering Vehicle (OMV); in situ servicing of a free-flying coorbiting materials processing platform; repair/refurbishment of Space Station payloads of substations; an in situ servicing of geostationary satellites by means of an Orbital Transfer Vehicle (OTV). The potential applications of three different automation technologies are examined, including: teleoperation; robotics; and artificial intelligence. Consideration is also given to the potential applications of the Space Station data system in support of servicing activities. A list of the more common terms of automation technology is provided.
This research analyzes four areas: (1) Improved Techniques for Optical Measurement; (2) KC-135 Low Gravity Simulation Flight Preparation; (3) In-Line Holographic Microscopy; and (4) Holographic Optical Schlieren System (HOSS). The first task provides for laboratory breadboarding of advanced optical measurement techniques which appear promising for use in Material Processing System (MPS) flight experiments. A laboratory schlieren system has been constructed which simulates a similar optical system on the Fluids Experiment System (FES) which is to be flown on Spacelab 3. The second task allows improved optical systems and breadboards to be built for experiments and hardware tests on the KC-135 aircraft. A new, more stable Mach-Zehnder interferometer has been developed and components have been ordered. The third task is concerned with improvements on the optical system being used to study immiscible fluids. Experiments studying the dynamics of nucleation and the separation of immiscible fluids have been conducted. The four task involves building breadboard reconstruction systems for holograms taken in the HOSS. The HOSS is an early prototype of the Fluids Experiments System (FES) which is scheduled to fly on Spacelab 3.