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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 541 records · Page 30
All sourcesNASA NTRSDOE OSTI
NASA NTRS1969

Lunar soil coefficient of friction determined from Surveyor data and laboratory tests

A series of laboratory tests on simulated soils was conducted to evaluate some of these physical properties. Using soils similar to lunar soil composition, particle size distribution, and cohesion as determined from the Surveyor mission, the coefficient of friction and bulk density were evaluated by reproducing soils with the same force vs penetration characteristics as demonstrated at the Surveyor landing sites. The determination of soil coefficient of friction is presented in this paper; the soil density is treated separately in the previous paper’ of this report.

Choate, R.↗
NASA NTRS1971

Development of a wideband wattmeter as a laboratory instrument

A portable, solid state, wideband wattmeter has been developed as a general purpose type of laboratory instrument. Its circuit and component investigations and evaluation data are presented. A prototype unit was used extensively, and served as the basis for a second instrument incorporating refined circuitry and improved packaging. The wattmeter provides true four quadrant operation which permits instantaneous indication of real power as an oscilloscope display. Major performance factors are: frequency bandwidth DC to 1 MHz plus or minus 1 db; current range 10 mA to 100 amperes peak; voltage range 1 volt to 1000 volts peak; accuracy plus or minus 2% of full scale reading. Oscilloscope data for typical switching transients in a transistor inverter circuit are included.

Landes, L. G.↗
NASA NTRS1971

Biochemical and physiological consequences of the Apollo flight diet.

Six male subjects subsisting on a typical Apollo flight diet for five consecutive days were evaluated for changes in biochemical and physiological status. Laboratory examinations failed to demonstrate any significant changes of the kind previously attributed to weightlessness, such as in serum electrolytes, endocrine values, body fluid, or hematologic parameters.

Hander, E. W.↗
NASA NTRS1974

Operations planning simulation model extension study. Volume 1: Long duration exposure facility ST-01-A automated payload

Ground processing and operation activities for selected automated and sortie payloads are evaluated. Functional flow activities are expanded to identify payload launch site facility and support requirements. Payload definitions are analyzed from the launch site ground processing viewpoint and then processed through the expanded functional flow activities. The requirements generated from the evaluation are compared with those contained in the data sheets. The following payloads were included in the evaluation: Long Duration Exposure Facility; Life Sciences Shuttle Laboratory; Biomedical Experiments Scientific Satellite; Dedicated Solar Sortie Mission; Magnetic Spectrometer; and Mariner Jupiter Orbiter. The expanded functional flow activities and descriptions for the automated and sortie payloads at the launch site are presented.

Marks, D. A.↗
NASA NTRS1975

Improved ultrasonic standard reference blocks

A program to improve the quality, reproducibility and reliability of nondestructive testing through the development of improved ASTM-type ultrasonic reference standards is described. Reference blocks of aluminum, steel, and titanium alloys were considered. Equipment representing the state-of-the-art in laboratory and field ultrasonic equipment was obtained and evaluated. Some RF and spectral data on ten sets of ultrasonic reference blocks were taken as part of a task to quantify the variability in response from nominally identical blocks. Techniques for residual stress, preferred orientation, and microstructural measurements were refined and are applied to a reference block rejected by the manufacturer during fabrication in order to evaluate the effect of metallurgical condition on block response.

Eitzen, D. G.↗
NASA NTRS1976

Command decoder unit

The design and testing of laboratory hardware (a command decoder unit) used in evaluating space shuttle instrumentation, data processing, and ground check-out operations is described. The hardware was a modification of another similar instrumentation system. A data bus coupler was designed and tested to interface the equipment to a central bus controller (computer). A serial digital data transfer mechanism was also designed. Redundant power supplies and overhead modules were provided to minimize the probability of a single component failure causing a catastrophic failure. The command decoder unit is packaged in a modular configuration to allow maximum user flexibility in configuring a system. Test procedures and special test equipment for use in testing the hardware are described. Results indicate that the unit will allow NASA to evaluate future software systems for use in space shuttles. The units were delivered to NASA and appear to be adequately performing their intended function. Engineering sketches and photographs of the command decoder unit are included.

Source record↗
NASA NTRS1976

Improved ultrasonic standard reference blocks

A program to improve the quality, reproducibility and reliability of nondestructive testing through the development of improved ASTM-type ultrasonic reference standards is described. Reference blocks of aluminum, steel, and titanium alloys are to be considered. Equipment representing the state-of-the-art in laboratory and field ultrasonic equipment was obtained and evaluated. RF and spectral data on ten sets of ultrasonic reference blocks have been taken as part of a task to quantify the variability in response from nominally identical blocks. Techniques for residual stress, preferred orientation, and micro-structural measurements were refined and are applied to a reference block rejected by the manufacturer during fabrication in order to evaluate the effect of metallurgical condition on block response. New fabrication techniques for reference blocks are discussed and ASTM activities are summarized.

Eitzen, D. G.↗
NASA NTRS1977

Methods of reducing low frequency cabin noise and sonically induced stresses, based on the intrinsic structural tuning concept

Control of low frequency interior noise has been difficult in all commercial and general aviation aircraft, since the existing sound attenuation techniques are less effective at these frequencies. Therefore low frequency cabin noise and sonically induced stresses can be reduced mainly by a proper design of the fuselage structure. For this purpose, a concept based on intrinsic tuning and damping of fuselage structural elements has been under development at Boeing for the past three years. This paper describes the results of some laboratory and field tests that were conducted for evaluation of the concept.

Sengupta, G.↗
NASA NTRS1978

Strainrange partitioning behavior of the nickel-base superalloys, Rene 80 and 100

A study has been made to assess the ability of the method of Strainrange Partitioning (SRP) to both correlate and predict high-temperature low-cycle fatigue lives of nickel-base superalloys for gas turbine applications. SRP is shown to correlate the cyclic lives of the baseline tests to within factors of nearly two. The partitioned strainrage versus life relationships for uncoated Rene 80 and cast IN 100 have also been determined from the ductility normalized-strainrange partitioning equations. These were used to predict the cyclic lives of the baseline tests. Predicted and observed cyclic lives agreed to within factors of nearly three. The life predictability of the method is also verified for cast IN 100 by applying the baseline results to the cyclic-life prediction of a series of complex strain-cycling tests with multiple hold periods at constant strain. It is concluded that the method of SRP can correlate and predict the cyclic lives of laboratory specimens of the nickel-base superalloys evaluated in this program.

Halford, G. R.↗
NASA NTRS1979

Some aspects of hydrology in the GLAS GCM

The response of hydrology in the Laboratory for Atmospheric Sciences General Circulation Model is evaluated. The results show that the distribution of precipitation agrees fairly well with observations of precipitation and that the model and that the model tends to maintain the hydrological balance.

Godbole, R.↗
NASA NTRS1978

Screening materials for smoke evolution

The density of smoke produced by burning or smoldering materials is a factor that affects the ability of occupants to escape from a burning structure and the effectiveness of firefighters. Accordingly, considerable effort is being spent on developing materials that minimize the amount of smoke without impairing their performance characteristics. In the present paper, laboratory tests on such materials are described and evaluated. It is seen that the National Bureau of Standards smoke test and the Ohio State University release-rate test are the most promising for screening materials for smoke evolution. It is shown that, for plastics, smoke obscuration is a more realistic concern than smoke toxicity.

Hilado, C. J.↗
NASA NTRS1983

Skeletal and body composition evaluation

Research on radiation detectors for absorptiometry; analysis of errors affective single photon absorptiometry and development of instrumentation; analysis of errors affecting dual photon absorptiometry and development of instrumentation; comparison of skeletal measurements with other techniques; cooperation with NASA projects for skeletal evaluation in spaceflight (Experiment MO-78) and in laboratory studies with immobilized animals; studies of postmenopausal osteoporosis; organization of scientific meetings and workshops on absorptiometric measurement; and development of instrumentation for measurement of fluid shifts in the human body were performed. Instrumentation was developed that allows accurate and precise (2% error) measurements of mineral content in compact and trabecular bone and of the total skeleton. Instrumentation was also developed to measure fluid shifts in the extremities. Radiation exposure with those procedures is low (2-10 MREM). One hundred seventy three technical reports and one hundred and four published papers of studies from the University of Wisconsin Bone Mineral Lab are listed.

Mazess, R. B.↗
NASA NTRS1985

Challenges of developing an electro-optical system for measuring man's operational envelope

In designing work stations and restraint systems, and in planning tasks to be performed in space, a knowledge of the capabilities of the operator is essential. Answers to such questions as whether a specific control or work surface can be reached from a given restraint and how much force can be applied are of particular interest. A computer-aided design system has been developed for designing and evaluating work stations, etc., and the Anthropometric Measurement Laboratory (AML) has been charged with obtaining the data to be used in design and modeling. Traditional methods of measuring reach and force are very labor intensive and require bulky equipment. The AML has developed a series of electro-optical devices for collecting reach data easily, in computer readable form, with portable systems. The systems developed, their use, and data collected with them are described.

Woolford, B.↗
NASA NTRS1984

Spacelab - The first mission and beyond

The recent successful flight of Spacelab 1, while being the culmination of over 10 years of international cooperation, is seen as just the start of a new era in manned scientific operations in orbit. This paper highlights the objectives and results of that first mission, as well as describing the international Spacelab program, its concept, and its history. Then looking to the future, the plans for utilizing Spacelab, its versatility and potential to the science community and its continuing evolution are discussed. Plans for substantially improving the cost effectiveness of Spacelab are examined including the use of dedicated discipline laboratories and small payload carriers. Finally, the paper evaluates the importance of incorporating Spacelab technology, concepts, lessons learned, and methodology into the development and utilization of an international Space Station over the next decade.

James, E.↗
NASA NTRS1988

Infrared radiometric technique in temperature measurement

One class of commercially available imaging infrared radiometers using cooled detectors is sensitive to radiation over the 3 to 12 micron wavelength band. Spectral filters can tailor instrument sensitivity to specific regions where the target exhibits optimum radiance. The broadband spectral response coupled with real time two-dimensional imaging and emittance/background temperature corrections make the instruments useful for remote measurement of surface temperatures from -20 C to +1500 C. Commonly used radiometric techniques and assumptions are discussed, and performance specifications for a typical modern commercial instrument are presented. The potential usefulness of an imaging infrared radiometer in space laboratories is highlighted through examples of research, nondestructive evaluation, safety, and routine maintenance applications. Future improvements in instrument design and application of the radiometric technique are discussed.

Glazer, S.↗
NASA NTRS1989

Triton - Do we see to the surface?

The quantity and physical state of methane and nitrogen in the atmosphere of Neptune's satellite Triton and on the surface are evaluated by means of new telescopic data and laboratory measurements of these volatiles. Methane ice is seen in some spectral regions, indicating that the atmosphere is sufficiently transparent to permit sunlight penetration to the surface. Some of the molecular nitrogen absorption occurs in the atmosphere, though some must occur in condensed nitrogen (liquid or solid) on Triton's surface, or in a thin cloud of condensed nitrogen. The Voyager spacecraft cameras should see the surface of Triton.

Cruikshank, D. P.↗
NASA NTRS1989

The role of computerized modeling and simulation in the development of life support system technologies

Computerized modeling and simulation (CMAS) is a tool that can greatly reduce both the time and cost of technology development. CMAS refers to computer methods for correlating, storing, and retrieving property data for chemical species and for solving the phenomenological equations of physical/chemical processes. Furthermore, process conditions based on properties of materials, mass, and energy balances; equipment sizing based on rate processes; and the governing equations for unit operations can be determined using CMAS. CMAS systems can be used to evaluate an LSS process with minimal requirements for laboratory experimentation. A CMAS model is presented for a vapor compression distillation system(VCD) for reclaiming water from urine.

Modell, Michael↗
NASA NTRS1993

A laboratory model of a hydrogen/oxygen engine for combustion and nozzle studies

A small laboratory diagnostic thruster was developed in order to evaluate approaches for the use of temperature and pressure sensors for the investigation of low thrust rocket flowfields. Tests were performed at chamber pressures of about 255 kPa, 370 kPa, and 500 kPa with oxidizer/fuel mixture ratios between 4.0 and 8.0. Two gaseous hydrogen/gaseous oxygen injector designs were tested with 60 and 75 fuel film cooling. The results of hot-wire tests showed the thruster and instrumentation designs to be effective. Azimuthal temperature distributions were found to be a function of operating conditions and hardware configuration. Results indicated that small differences in injector design can result in dramatically different thruster performance and wall temperature behavior. However, the importance of these injector effects may be decreased by operating at a high fuel film cooling rate.

Morren, Sybil H.↗