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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 325 records · Page 18

Past experience Skylab mission

The design of the Skylab missions, 1973 to 1974, was intended to exclude any direct handling of hazardous, toxic, or reactive materials. The materials processing facility and multipurpose furnace provided a contained environment for conducting metals melting, brazing, sphere forming, and crystal growth experiments. At the end of the third mission, following the completion of all other experiments, the materials processing facility was used for a series of flammability experiments. The flammability tests were done last because of the contamination expected from the burning of the materials within the facility. The flammability tests demonstrated a number of peculiar effects that have implications for future design (fire detection, location, and suppression/control). Although the results of the flammability tests contain lessons appropriate to planning, a number of events during the flight illustrate situations or conditions that pose considerations beyond the commonly accepted range of concern for safety-related matters. This presentation includes a discussion of: Skylab flammability studies and the implications for fire suppression/control; false fire alarms and the Skylab fire detection system; space environmental effects on materials that are normally benign; spills/release of contaminants; the detrimental effect that the release of non-hazardous materials have on detection systems; and the problem of locating sources/originating point of hazards.

Pogue, William↗

Initial materials evaluation of the thermal control surfaces experiment (S0069)

The Thermal Control Surface Experiment (TCSE) was flown on the NASA Long Duration Exposure Facility (LDEF) with the basic objective of determining the effects of the near-earth orbital environment and the LDEF induced environment on spacecraft thermal control surfaces. The TCSE was a comprehensive experiment that combined in-space measurements with extensive post-flight analyses of thermal control surfaces to determine the effects of exposure to the low earth orbit space environment. The TCSE is the first space experiment to measure the optical properties of thermal control surfaces the way they are routinely measured in the laboratory. The specific mission objectives of the TCSE were to: (1) determine the effects of the natural and induced space environment on thermal control surfaces; (2) provide in-space performance data on thermal control surfaces; (3) provide in-space comparison to ground-based environmental testing of materials; and (4) develop and prove instrumentation to perform in-space optical testing of materials. Various aspects of the experiment are discussed.

Donald R. Wilkes↗

Remote sensing operations (multispectral scanner and photographic) in the New York Bight, 22 September 1975

Ocean dumping of waste materials is a significant environmental concern in the New York Bight. One of these waste materials, sewage sludge, was monitored in an experiment conducted in the New York Bight on September 22, 1975. Remote sensing over controlled sewage sludge dumping included an 11-band multispectral scanner, fiver multispectral cameras and one mapping camera. Concurrent in situ water samples were taken and acoustical measurements were made of the sewage sludge plumes. Data were obtained for sewage sludge plumes resulting from line (moving barge) and spot (stationary barge) dumps. Multiple aircraft overpasses were made to evaluate temporal effects on the plume signature.

Johnson, R. W.↗

Artificial meteor ablation studies

Artificial meteor ablation was performed on natural minerals, composed predominately of magnetite and hematite, using an arc heated plasma stream of air. Analysis of the ablated debris indicated most was composed of two or more minerals. The more volatile elements were depleted and the relative abundance of Fe increased as a result of both volatile depletion and a reduction in its oxidation state. Hematite was converted to magnetite in the ablation zone, and quartz and apatite minerals were converted to an Fe-rich glass consisting of varying amounts of Si, P, Cl, and Ca, depending upon the accessory minerals available at the time of melting. Artificially created ablation products from iron oxides exhibited unique properties depending on the composition of the original material and the environmental conditions of formation. In addition to the accepted elemental criteria, these properties were morphologic characteristics, textural parameters, and the existence of metastable minerals.

Blanchard, M. B.↗

Corrosion and fatigue of surgical implants

Implants for the treatment of femoral fractures, mechanisms leading to the failure or degradation of such structures, and current perspectives on surgical implants are discussed. Under the first heading, general usage, materials and procedures, environmental conditions, and laboratory analyses of implants after service are considered. Corrosion, crevice corrosion, stress corrosion cracking, intergranular corrosion, pitting corrosion, fatigue, and corrosion fatigue are the principal degradation mechanisms described. The need for improvement in the reliability of implants is emphasized.

Lisagor, W. B.↗

Photovoltaic test and demonstration project

The primary objectives of the Photovoltaic Test and Demonstration Project are: (1) to determine operating characteristics for different solar cell systems and subsystems, (2) to prove, through tests and demonstrations, that solar cell systems can satisfy the requirements of potentially attractive residential, commercial, industrial, and smaller terrestrial applications, (3) to devise and implement the methodology, techniques and equipment to make accurate and reproducible measurements of solar cell and array performance, and diagnostic measurements on solar cells, modules and arrays, and (4) to determine the endurance of solar cell modules, component parts, and materials under expected environmental conditions.

Forestieri, A. F.↗

Applications notice

The discipline programs of the Space and Terrestrial (S&T) Applications Program are described and examples of research areas of current interest are given. Application of space techniques to improve conditions on earth are summarized. Discipline programs discussed include: resource observations; environmental observations; communications; materials processing in space; and applications systems/information systems. Format information on submission of unsolicited proposals for research related to the S&T Applications Program are given.

Source record↗

NASCAP modelling of high-voltage power system interactions with space charged-particle environments

The NASA Charging Analyzer Program (NASCAP), an engineering tool capable of analyzing the impact of the charged particle environment on spacecraft surfaces and systems, is described. NASCAP is a quasi-static computational program which analyzes the charging of a 3-dimensional complex body as a function of time and system-generated voltages for given space environmental conditions. The material properties of the surfaces are taken into account; the surface potentials, low energy sheath, potential distribution in space and particle trajectories are calculated. An application of NASCAP to a simple space solar power station consisting of two 6 m by 18 m solar array wings surrounding a central body is presented. Each solar array wing is considered to be divided into three regions operating at 2000 volts. Results of NASCAP analysis of the system for a normal environment and a moderate geomagnetic substorm environment are discussed.

Stevens, N. J.↗

Microwave limb sounder, graphite epoxy support structure

The manufacturing and processing procedures which were used to fabricate a precision graphite/epoxy support structure for a spherical microwave reflecting surface are described. The structure was made fromm GY-70/930 ultra high modulus graphite prepreg, laminated to achieve an isotropic in plane thermal expansion of less than + or - 0.1 PPM/F. The structure was hand assembled to match the interface of the reflective surface, which was an array of 18 flexure supported, aluminum, spherically contoured tiles. Structural adhesives were used in the final assembly to bond the elements into their final configuration. A eutectic metal coating was applied to the composite surface to reduce dimensional instabilities arising from changes in the composite epoxy moisture content due to environmental effects. Basic materials properties data are reported and the results of a finite element structural analysis are referenced.

Pynchon, G.↗

Review of factors that influence fretting wear

An assessment is made of presently obtained as well as published results in order to characterize the effects of contact conditions, environmental conditions, and material properties and behavior on fretting wear. The importance of material properties is discussed on the basis of interaction with other factors during fretting. While the isolated effect of contact load, fretting amplitude, temperature and atmosphere have been well explored, especially for the case mild steel, a deficiency is noted in studies of the effects of contact geometry and relative humidity, as well as the interaction of various fretting parameters.

Bill, R. C.↗

The NASA space power technology program

The NASA Space Power Technology Program is driven by missions extending 30 years into the future. The general characteristics of these missions will be described insofar as they drive power system requirements. The various elements of the program will be presented and put into this mission context. Specific technologies discussed include: solar dynamic, nuclear, and photovoltaic power generation; electrochemical energy storage; power generation; electrochemical energy storage; thermal management; and power management and distribution, including environmental interactions and materials. These programs are strongly interlinked and interdependent and focus on meeting a broad range of agency and national needs.

Vanlandingham, E. E.↗

An overview of Japanese CELSS research activities

Development of Controlled Ecological Life Support System (CELSS) technology is inevitable for future long duration stays of human beings in space, for lunar base construction and for manned Mars flight programs. CELSS functions can be divided into 2 categories, Environmental Control and Material Recycling. Temperature, humidity, total atmospheric pressure and partial pressure of oxygen and carbon dioxide, necessary for all living things, are to be controlled by the environment control function. This function can be performed by technologies already developed and used as the Environment Control Life Support System (ECLSS) of Space Shuttle and Space Station. As for material recycling, matured technologies have not yet been established for fully satisfying the specific metabolic requirements of each living thing including human beings. Therefore, research activities for establishing CELSS technology should be focused on material recycling technologies using biological systems such as plants and animals and physico-chemical systems, for example, a gas recycling system, a water purifying and recycling system and a waste management system. Japanese research activities were conducted and will be continued accordingly.

Nitta, Keiji↗

The NASA atomic oxygen effects test program

The NASA Atomic Oxygen Effects Test Program was established to compare the low earth orbital simulation characteristics of existing atomic oxygen test facilities and utilize the collective data from a multitude of simulation facilities to promote understanding of mechanisms and erosion yield dependence upon energy, flux, metastables, charge, and environmental species. Four materials chosen for this evaluation include Kapton HN polyimide, FEP Teflon, polyethylene, and graphite single crystals. The conditions and results of atomic oxygen exposure of these materials is reported by the participating organizations and then assembled to identify degrees of dependency of erosion yields that may not be observable from any single atomic oxygen low earth orbital simulation facility. To date, the program includes 30 test facilities. Characteristics of the participating test facilities and results to date are reported.

Banks, Bruce A.↗

Numerical model of solar dynamic radiator for parametric analysis

Growth power requirements for Space Station Freedom will be met through addition of 25 kW solar dynamic (SD) power modules. The SD module rejects waste heat from the power conversion cycle to space through a pumped-loop, multi-panel, deployable radiator. The baseline radiator configuration was defined during the Space Station conceptual design phase and is a function of the state point and heat rejection requirements of the power conversion unit. Requirements determined by the overall station design such as mass, system redundancy, micrometeoroid and space debris impact survivability, launch packaging, costs, and thermal and structural interaction with other station components have also been design drivers for the radiator configuration. Extensive thermal and power cycle modeling capabilities have been developed which are powerful tools in Station design and analysis, but which prove cumbersome and costly for simple component preliminary design studies. In order to aid in refining the SD radiator to the mature design stage, a simple and flexible numerical model was developed. The model simulates heat transfer and fluid flow performance of the radiator and calculates area mass and impact survivability for many combinations of flow tube and panel configurations, fluid and material properties, and environmental and cycle variations. A brief description and discussion of the numerical model, it's capabilities and limitations, and results of the parametric studies performed is presented.

Rhatigan, Jennifer L.↗

Working group written presentation: Trapped radiation effects

The results of the Trapped Radiation Effects Panel for the Space Environmental Effects on Materials Workshop are presented. The needs of the space community for new data regarding effects of the space environment on materials, including electronics are listed. A series of questions asked of each of the panels at the workshop are addressed. Areas of research which should be pursued to satisfy the requirements for better knowledge of the environment and better understanding of the effects of the energetic charged particle environment on new materials and advanced electronics technology are suggested.

Vampola, Alfred L.↗