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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 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

Thermal design and experiment thermal integration of the Long Duration Exposure Facility

The Long Duration Exposure Facility (LDEF) is a large (14 feet diameter by 30 feet long) Shuttle transported, reusable spacecraft. The LDEF can accommodate up to 13,000 pounds of experiments mounted in 86 standard trays. This paper describes the philosophy and approach used for the passive thermal design of the LDEF. Also discussed are the standardized guidelines and techniques used in the thermal design and integration of approximately 50 different thermally passive experiments. A technique for reducing multinode thermal models of experiments to 2 nodes is also presented. This approach allows the efficient thermal integration of large numbers of experiments with the LDEF spacecraft.

Greene, R. F., Jr.↗
NASA NTRS1977

Analysis of the passive stabilization of the long duration exposure facility

The nominal Long Duration Exposure Facility (LDEF) configurations and the anticipated orbit parameters are presented. A linear steady state analysis was performed using these parameters. The effects of orbit eccentricity, solar pressure, aerodynamic pressure, magnetic dipole, and the magnetically anchored rate damper were evaluated to determine the configuration sensitivity to variations in these parameters. The worst case conditions for steady state errors were identified, and the performance capability calculated. Garber instability bounds were evaluated for the range of configuration and damping coefficients under consideration. The transient damping capabilities of the damper were examined, and the time constant as a function of damping coefficient and spacecraft moment of inertia determined. The capture capabilities of the damper were calculated, and the results combined with steady state, transient, and Garber instability analyses to select damper design parameters.

Siegel, S. H.↗
NASA NTRS1978

Space qualification of optical instruments using the NASA Long-Duration Exposure Facility

The NASA Long-Duration Exposure Facility (LDEF), designed for the in situ testing of optical instrumentation in the space environment is described. The LDEF is basically a reusable structure which is three-axis gravity-gradient stabilized when flying free in space. The structure weighs about 8,000 lbs. and accommodates experiment trays weighing about 10,000 lbs. A vacuum exposure control canister is being designed for controlled exposure experiments. The LDEF will have an experiment power and data system and a shuttle bay environmental measurements system is being designed for measuring parameters such as acoustics, vibration, acceleration. The induced environment contamination monitor will evaluate the contamination levels of shuttle payloads. Experiments currently under development include the evaluation of active optical components and the study of fiber optic data transmission.

Clark, L. G.↗
NASA NTRS1971

Long-duration exercise at moderate work loads

Metabolic effects of long duration exercise at moderate work loads including tables of heart rate, rectal temperature, minute volume, water balance, and respiratory quotient

Camacho, A.↗
NASA NTRS1977

The long duration exposure facility - A test bed for space technology development

The long duration exposure facility (LDEF) is being developed by NASA to accommodate, using the Shuttle, a class of technology, science, and applications experiments which require a free-flying exposure in space. The LDEF offers an attractive approach to experiments which require long-term exposure in space. LDEF missions up to 10 years duration are possible and requested by researchers. Attention is given to the LDEF concept and the operations, plans for technology testing in space, and aspects of investigator participation.

Dibattista, J. D.↗
NASA NTRS1977

Long duration exposure facility - A free-flying experiment carrier

The Long Duration Exposure Facility (LDEF) will complement and extend Shuttle operations with Spacelab and pallets. The LDEF is a passive stabilized structure which can accommodate a wide variety of users who have experiments which require a free-flying carrier for exposure in space. The experiments are contained in trays which are attached to the LDEF. This paper describes the LDEF concept and operation, the facility, mission characteristics, and plans for the selection of experiments to fly on LDEF.

Dibattista, J. D.↗
NASA NTRS1977

Long Duration Exposure Facility - A unique mode of Shuttle utilization

The Long Duration Exposure Facility (LDEF) is a Shuttle-transported, reusable, essentially passive facility with accommodations for a wide variety of experiments which require a free-flying carrier for exposure in space. Specifically, the LDEF is tailored to provide low-cost accommodations for experiments which have modest requirements for electrical power and data systems, and for experiments which benefit from postflight laboratory investigations with the retrieved experiment hardware. Each experiment for LDEF will be totally self-contained in a tray. As the interface with the facility has been minimized, the LDEF experimenters will be freed from many of the requirements which have complicated development of space experiments in the past.

Kinard, W. H.↗
NASA NTRS1971

Long-duration firings of a Mariner Mars 1969 catalytic reactor

Two long-duration tests were conducted with a surplus Mariner Mars 1969 monopropellant hydrazine reactor in an attempt to induce the washout phenomenon. The Mariner Mars 1969 reactor was chosen because it has a long development history and thus is well characterized. No washout occurred during either of the two 1000-s tests, although slow transients were observed in the reactor operation during what were nominally steady-state conditions. The 2000-s of operating time represents nearly an order of magnitude increase over the rated life of the engine.

Price, T. W.↗
NASA NTRS1976

Long Duration Exposure Facility - A multipurpose free-flying experiment carrier

The Long Duration Exposure Facility (LDEF) is being developed by NASA to accommodate, using the Space Shuttle, a class of technology, science and applications experiments which require a free-flying exposure in space, but which do not require a sophisticated or dedicated satellite. The facility is a simple reusable structure about 14 ft in diameter and 30 ft long, which is three-axis gravity-gradient stabilized when free flying in space. Various aspects of the LDEF are examined, including the attitude stabilization system, the experiment trays, the experiment exposure control canister,and the environment monitoring system. LDEF mission plans are considered, as is experiment selection - the space debris damage experiment, the thermal coating experiment, the solar cells and arrays experiment, and the active optical components experiment.

Kinard, W. H.↗