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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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Low cost, easily manufactured turnbuckle was developed for applying a predetermined load on strap assemblies. Unit consists of sleeve and nut assembled on turnbuckle that is pulled to predetermined load in tension test machine.
Heat shrinkable Teflon tubing is cut to size, slipped onto shaft, heated to shrink tightly to shaft, or machined to final outside diameter size. Shaft bushings fabricated from shrinkable Teflon tubing provide economic close fitting sleeves that prevent galling and contamination in valves.
The following basic types of gear reduction concepts were studied as being feasible power train systems for a low-bypass-ratio, single-spool, geared turbofan engine for general aircraft use: (1) single-stage external-internal reduction, (2) gears (offset shafting), (3) multiple compound idler gear system (concentric shafting), and (4) star gear planetary system with internal ring gear final output member (concentric shafting-counterrotation). In addition, studies were made of taking the accessories drive power off both the high-speed and low-speed shafting, using either face gears or spiral bevel gears. Both antifriction and sleeve-type bearings were considered for the external-internal and star-planet reduction concepts.
The Apollo 12 astronauts brought the Surveyor III television camera back from the moon in November 1969. Chemical analyses of a portion of television cable revealed changes in the glass fabric sleeve and in the wire insulation as a result of exposure to the lunar environment. Loss of volatile constituents from the glass fabric and a discoloration of the glass occurred. The Teflon layer on the wire showed a slight discoloration and possibly a slight change in its infrared spectrum. Both the polyimide layer and the Teflon layer of the wire insulation showed changes in tensile strength and elongation.
A description is given of a three dimensional hand force capability model for the seated operator and a biomechanical model for analysis of symmetric sagittal plane activities. The models are used to simulate and study human strengths for one and two handed tasks in zero gravity. Specific conditions considered include: (1) one hand active, (2) both hands active but with different force directions on each, (3) body bracing situations provided by portable foot restraint when standing and lap belt when seated, (4) static or slow movement tasks with maximum length of 4 seconds and a minimum rest of 5 minutes between exertions, and (5) wide range of hand positions relative to either the feet or bisection of a line connecting the hip centers. Simulations were also made for shirt sleeved individuals and for the male population strengths with anthropometry matching that of astronauts.
Eight high intensity portable fluorescent lights were produced. Three prototype lights were also produced, two of which were subsequently updated to the physical and operational configuration of the qualification and flight units. Positioning of lamp apertures and reflectors in these lights is such that the light is concentrated and intensified in a specific pattern rather than widely diffused. Indium amalgam control of mercury vapor pressure in the lamp gives high output at lamp ambient temperatures up to 105 C. A small amount of amalgam applied to each electrode stem helps to obtain fast warm-up. Shrinking a Teflon sleeve on the tube and potting metal caps on each end of the lamp minimizes dispersion of mercury vapor and glass particles in the event of accidental lamp breakage. Operation at 20 kHz allows the lamps to consume more power than at low frequency, thus increasing their light output and raising their efficiency. When used to expose color photographic film, light from the lamps produces results approximately equal to sunlight.
The paper defines the experimental phase of an objective to obtain the mechanical characteristics and coefficients required by the generalized form of Hooke's law for nylon-polyurethane-coated fabric. Test specimens were cylindrical fabric sleeves and were loaded in axial tension by an Instron, in hoop tension by pressurizing, and in shear by a torquing fixture. An extensive amount of strain data is included for a wide combination of the three membrane loads. The tests indicate highly nonlinear stress-strain characteristics of the fabric and a strong dependency on all three membrane loads.
An apparatus for measuring the thermoelectric properties of materials under high pressure is described that includes a pair of force transmitting assemblies constructed of thermally and electrically conductive material positioned between the ram and anvil of a press. Each force transmitting assembly has a small diameter pressing portion for contacting a face of the sample so that the sample can be squeezed between them. Each assembly also includes a heat exchanger to maintain the sample face at a controlled temperature, and an electrical conductor to carry current generated by the sample. A sleeve of thermally and electrically insulative material closely surrounds the pressing portions of the two assemblies.
A schematic of the developed tubular thermoelectric module is shown. It consists of alternate washers of n- and p-type lead telluride, separated by thin natural mica washers. Electrical continuity within the circuit is accomplished by cylindrical conductor rings located at the I.D. and O.D. of the lead telluride washers. The conductor rings are also separated by the same mica which separate the lead telluride washers. The result is a radially serpentine current path along the length of the module. The circuit is isolated from the structural claddings by thin sleeves of boron nitride. Circuit containment and heat transfer surfaces are provided by the inner and outer cladding, heat being transferred from a heat source at the inner clad, conducted radially outward through the lead telluride to the outer clad where the waste heat is removed by a heat rejection system.
An electrical wire is reported along whose length loops are formed at intervals and retained in a plastic capsule that allows unfolding of the loop when tension is exerted on the opposite ends of the wire. The capsule is formed by encompassing each loop with a sleeve of heat shrinkable synthetic plastic material which overlaps the loop and heat shrinking the overlapping portions. Thus, a length of electrical wire is formed which stores extra lengths of wire in the quantity needed to match the expected stretching of materials or elements such as ropes, cords and the like of high elongation to which the electrical wire may be attached.
This device is characterized by an elongated body having predetermined elastic properties. An applied tensile force of any magnitude, within a given range, imparts to the body an elongation of a predetermined length. The magnitude of applied tensile force is indicated as a function of the angular motion afforded the threaded sleeve mounted on the body.
Analytical and experimental studies made of heat flow in the exothermic brazing unit in the M552 experiment are described. The emphasis of the studies was placed on heat flow in the tube and the sleeve during a period from ignition to the time when the brazing alloy solidifies. Experiments were made of three specimens tested in a ground-based laboratory. Heat flow was determined by thermocouples. The analytical study covered two phases: (1) the effect of reduced gravity on heat flow in the exothermic brazing unit; and (2) the development of analytical models. The major mode of heat transfer was conduction and the effect of gravity was minimal. Good agreements were obtained between experimental and analytical results indicating the soundness of the analytical models.
Possible applications are considered of a master-sleeve teleoperator arm system, developed in exoskeletal space suit technology, as therapeutic aid, orthotic device, or for therapy on patients with neurological disorders.
The package considered is intended for the channel electron multiplier (CEM) detectors which are to be used for the extreme ultraviolet telescope and helium glow detector instruments of the Apollo-Soyuz test project. In the package design selected, the cone of the CEM is supported at the front end by a silicone rubber ring which is molded in place and self-bonded to both the cone and the housing wall. The helix is supported and insulated from the housing by a fiber glass sleeve which is bonded to the inside of the housing.
An alternate thermal protection system for the Skylab space station cluster was deemed necessary shortly after launch when severe damage occured to the orbital workshop as it passed through the period of maximum dynamic pressure. Data indicated that the combination micrometeoroid and thermal shield on the sun facing side of the vehicle had been destroyed. The simultaneous design, fabrication, and test of the Skylab Parasol System which was completed in 6 days of around-the-clock effort is described. The Skylab Parasol design was selected as the primary sunshade device based on simplicity of design, ability to fabricate quickly, and early demonstration of a working prototype which featured semiautomatic deployment from within the workshop under shirt sleeve environment conditions.
Abrasion-resistant thermal barrier, consisting of two layers of woven fabric or braided sleeving with bulk insulation sandwiched between, shows excellent resilience even after compression at temperatures above 980C.
Spacelab is an orbital facility that provides a pressurized, 'shirt-sleeve' laboratory (the module) and an unpressurized platform (the pallet), together with certain standard services. It is a reusable system, which is transported to and from orbit in the cargo bay of the space shuttle orbiter and remains there throughout the flight. Spacelab extends the shuttle capability, and the Orbiter/Spacelab combination can be regarded as a short-stay space station which can remain in orbit for up to 30 days (the nominal mission duration is 7 days). In orbit, the experiments carried by Spacelab are operated by a team of up to four payload specialists who normally work in the laboratory, but spend their off-duty time in the orbiter cabin. The purpose of Spacelab is to provide a ready access to space for a broad spectrum of experimenters in many fields and from many nations. Low-cost techniques are envisaged for experiment development, integration and operation. The aim of this document is to provide a brief summary of Spacelab design characteristics and its use potential for experimenters wishing to take advantage of the unique opportunities offered for space experimentation.
The design and cost analysis of an accessible focal plane telescope for Spacelab is presented in blueprints, tables, and graphs. Topics covered include the telescope tube, the telescope mounting, the airlock plus Spacelab module aft plate, the instrument adapter, and the instrument package. The system allows access to the image plane with instrumentation that can be operated by a scientist in a shirt sleeve environment inside a Spacelab module.