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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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

Flight equipment supporting metabolic experiments on SLS-1

Five experiments in different aspects of human metabolism will be performed on Spacelab Life Sciences-1. Nine items of equipment from the Life Sciences Laboratory Equipment inventory will be used: the rack-mounted centrifuge, the hematocrit centrifuge, the low-gravity centrifuge, a body-mass measurement device, a urine monitoring system, the Spacelab refrigerator/freezer, the Orbiter refrigerator, an in-flight blood collection system, and a pocket voice recorder. In addition, each experiment will require some specialized equipment such as incubators and culture blocks for an immunology experiment, and tracers for a fluid and electrolyte experiment and a hematology experiment. The equipment for these experiments has been developed over many years, in some cases since the Skylab program in the early 1970s, and has been certified for use on the Space Shuttle.

Leach, Carolyn S.↗
NASA NTRS1992

Space Cryogenics Workshop, 10th, Cleveland, OH, June 18-20, 1991, Proceedings

The present workshop on cryogenics discusses the anomalous on-orbit behavior of the Cosmic Background Explorer Dewar, the SHOOT orbital operations, cooling options for Astromag, and space IR telescope facility mission and cryogenic design. Attention is given to the design of a spaceworthy adiabatic demagnetization refrigerator, the evaluation of metal hydride compressors for applications in Joule-Thomson cryocoolers, diaphragm Stirling cryocooler developments, and a computer simulation model for Stirling refrigerators. Topics addressed include low-gravity thermal stratification of liquid helium on SHOOT, a screening program to select a resin for gravity probe-B composites, a simplified generic cryostat thermal model for predicting cryogen mass and lifetime, and the effect of gas mass flux on cryogenic liquid jet breakup. Also discussed are damping criteria for thermal acoustic oscillations in slush and liquid hydrogen systems, an STS-based cryogenic fluid management experiment, and the design and testing of a cryogenic mixer pump.

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NASA NTRS1992

CONE - An STS-based cryogenic fluid management experiment

An overview of the CONE program is presented which includes a definition of the technology addressed by CONE and a baseline experiment set, a description of the experimental and support subsystems, interface requirements between the STS and the experiment carrier (Hitchhiker M), and the reusability and expansion capacity for additional experiment flights. CONE evaluates three primary technologies: the active thermodynamic vent system, the passive thermodynamic vent system, and liquid acquisition device performance. The cryogenic fluid management technology database that the system offers will allow for efficient subcritical cryogenic system designs for operation in a low-gravity environment. This system maximizes the balance between existing component technology and the need for the development of a cryogenic-fluid-management (CFM) test bed to investigate and demonstrate methods of storage and handling arenas.

Bell, R. S.↗
NASA NTRS1992

Intensified array camera imaging of solid surface combustion aboard the NASA Learjet

An intensified array camera has been used to image weakly luminous flames spreading over thermally thin paper samples in a low-gravity environment aboard the NASA-Lewis Learjet. The aircraft offers 10 to 20 sec of reduced gravity during execution of a Keplerian trajectory and allows the use of instrumentation that is delicate or requires higher electrical power than is available in drop towers. The intensified array camera is a charge intensified device type that responds to light between 400 and 900 nm and has a minimum sensitivity of 10(exp 6) footcandles. The paper sample, either ashless filter paper or a lab wiper, burns inside a sealed chamber which is filled with 21, 18, or 15 pct. oxygen in nitrogen at one atmosphere. The camera views the edge of the paper and its output is recorded on videotape. Flame positions are measured every 0.1 sec to calculate flame spread rates. Comparisons with drop tower data indicate that the flame shapes and spread rates are affected by the residual g level in the aircraft.

Weiland, Karen J.↗
NASA NTRS1992

Experiment specific processing of residual acceleration data

To date, most Spacelab residual acceleration data collection projects have resulted in data bases that are overwhelming to the investigator of low-gravity experiments. This paper introduces a simple passive accelerometer system to measure low-frequency accelerations. Model responses for experiments using actual acceleration data are produced and correlations are made between experiment response and the accelerometer time history in order to test the idea that recorded acceleration data and experimental responses can be usefully correlated. Spacelab 3 accelerometer data are used as input to a variety of experiment models, and sensitivity limits are obtained for particular experiment classes. The modeling results are being used to create experiment-specific residual acceleration data processing schemes for interested investigators.

Rogers, Melissa J. B.↗
NASA NTRS1992

Residual acceleration data analysis for Spacelab missions

A two-level reduction plan is developed analytically with references to existing experimental data that can be used to develop accelerometer databases for postflight experiment analyses. Residual-acceleration data from previous experiments are studied with attention given to the differences in magnitude among the databases. First-level processing is based on the identification of instances in which tolerable acceleration levels are exceeded so that the time intervals requiring further scrutiny are found. Acceleration time histories including magnitude and orientation are utilized with frequency data for the second level of processing, and the data required for a given time window are reduced by means of data decimation. The identification and processing of limited windows of acceleration data facilitates the characterization of the acceleration environment. These characterizations are of use in the design, location, and utilization of low-gravity laboratory equipment.

Rogers, Melissa J. B.↗
NASA NTRS1991

Welding in space and the construction of space vehicles by welding; Proceedings of the Conference, New Carrollton, MD, Sept. 24-26, 1991

The present conference discusses such topics in spacecraft welding as the NASA Long Duration Exposure Facility's evidence on material properties degradation, EVA/telerobotic construction techniques, welding of the superfluid helium on-orbit transfer flight demonstration tanks and hardware, electron-beam welding of aerospace vehicles, variable-polarity plasma arc keyhole welding of Al, aircraft experiments of low-gravity fusion welding, flash-butt welding of Al alloys, and a computer-aided handbook for space welding fabrication. Also discussed are the welded nozzle extension for Ariane launch vehicles, the existence of on-orbit cold-welding, structural materials performance in long-term space service, high-strength lightweight alloys, steels, and heat-resistant alloys for aerospace welded structures, the NASA-Goddard satellite repair program, and the uses of explosion welding and cutting in aerospace engineering.

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NASA NTRS1993

Magnetic Compensation For Gravitational Pressure Gradient

In technique for partial simulation of low gravitation in diamagnetic or paramagnetic liquid, magnetic field having suitable gradient produces force counteracting gravitational force. Technique makes possible to perform low-gravity experiments on ground, at considerably less expense than in outer space.

Israelsson, Ulf E.↗
NASA NTRS1992

The VTRE Program: An overview

The Vented Tank Resupply Experiment (VTRE) Program is a NASA In-Space Technology Experiments Program (IN-STEP) that will develop, and fly a small, low cost space experiment to investigate, develop, and acquire needed data to extend and advance the technology of capillary vane fluid management devices to applications requiring direct venting of gas from tanks in low-gravity. GAS venting may be required for control of pressure, or to allow low-g fill of a tank with liquid while holding a constant tank back pressure by gas venting. Future space applications requiring these fluid management capabilities include both cryogenic and Earth storable fluid systems. The experiment is planned as a Shuttle Hitchhiker payload, and will be developed around two transparent tanks equipped with capillary vane devices between which a test liquid can be transferred. Experiments will be conducted for vented transfer, direct venting, stability of liquid positioning to accelerations within and significantly above the design values, and fluid reorientation by capillary wicking of liquid into the vane device following intentional liquid upset.

Bailey, William J.↗
NASA NTRS1992

Combustion of Gaseous Fuels Under Reduced-Gravity Conditions

The need for an improved understanding of fires is becoming critically important with increased space travel and utilization. While the control of fires in low-gravity environments is not well understood, it is known that buoyancy significantly affects flame behavior and characteristics. The objective of this research is to gain a more fundamental understanding of fires, and to quantify flame behavior under reduced-gravity levels. Non-premixed flames of gaseous fuels are considered in this study because they are relatively simple and easy to control, yet embody mechanisms found in all types of combustion processes ranging from uncontrolled fires to practical combustion systems. This paper presents some recent results from microgravity studies of these flames. In addition, the potential usefulness of lunar- and Martian-based laboratories is discussed in order to understand the characteristics and behavior of fires in reduced-gravity environments.

Bahadori, M. Yousef↗
NASA NTRS1992

Lunar site characterization and mining

Lunar mining requirements do not appear to be excessively demanding in terms of volume of material processed. It seems clear, however, that the labor-intensive practices that characterize terrestrial mining will not suffice at the low-gravity, hard-vacuum, and inaccessible sites on the Moon. New research efforts are needed in three important areas: (1) to develop high-speed, high-resolution through-rock vision systems that will permit more detailed and efficient mine site investigation and characterization; (2) to investigate the impact of lunar conditions on our ability to convert conventional mining and exploration equipment to lunar prototypes; and (3) to develop telerobotic or fully robotic mining systems for operations on the Moon and other bodies in the inner solar system. Other aspects of lunar site characterization and mining are discussed.

Glass, Charles E.↗
NASA NTRS1992

Space Station Furnace Facility Core. Requirements definition and conceptual design study. Volume 2: Technical report. Appendix 6: Technical summary reports

The Space Station Furnace Facility (SSFF) is a modular facility for materials research in the microgravity environment of the Space Station Freedom (SSF). The SSFF is designed for crystal growth and solidification research in the fields of electronic and photonic materials, metals and alloys, and glasses and ceramics and will allow for experimental determination of the role of gravitational forces in the solidification process. The facility will provide a capability for basic scientific research and will evaluate the commercial viability of low-gravity processing of selected technologically important materials. The facility is designed to support a complement of furnace modules as outlined in the Science Capabilities Requirements Document (SCRD). The SSFF is a three rack facility that provides the functions, interfaces, and equipment necessary for the processing of the furnaces and consists of two main parts: the SSFF Core Rack and the two Experiment Racks. The facility is designed to accommodate two experimenter-provided furnace modules housed within the two experiment racks, and is designed to operate these two furnace modules simultaneously. The SCRD specifies a wide range of furnace requirements and serves as the basis for the SSFF conceptual design. SSFF will support automated processing during the man-tended operations and is also designed for crew interface during the permanently manned configuration. The facility is modular in design and facilitates changes as required, so the SSFF is adept to modifications, maintenance, reconfiguration, and technology evolution.

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NASA NTRS1992

OSSA Space Station Freedom science utilization plans

Long duration exposure to an essentially zero-gravity environment is a phenomenon exclusive to the Space Station Freedom that cannot be duplicated on Earth. The Freedom Station will offer periods of time on orbit extending to weeks and months rather than hours or days, allowing for in-depth space based research and analysis to a degree never before achieved. OSSA remains committed to exploiting the unique capabilities provided by the Space Station as well as other space-based facilities to study the nature of physical, chemical, and biological processes in a low-gravity environment and to apply these studies to advance science and applications in such fields as biomedical research, plant and animal physiology, exobiology, biotechnology, materials science, fluid physics, and combustion science. The OSSA focus is on progressive science investigations, many requiring hands-on scientist involvement using sophisticated experiment hardware. OSSA science utilization planning for the Freedom Station is firmly established. For this presentation, this planning is discussed in three general areas: OSSA goals and overall approach, the current and on-going program, and plans for space station utilization. In the first area, OSSA addresses its overall approach to space science research, its commitment to transition to Space Station Freedom, and its top-level strategy for the utilization of Freedom. The current and on-going program is next discussed, focusing on the various Spacelab series of missions which are providing the stepping-stones to Space Station Freedom. Selected science results from SLS-1 and USML-1 are cited which underline the value of properly outfitted laboratories in space in which crew-intensive experiment interactions are possible. The presentation is concluded with a discussion of top-level goals and strategies for utilizing the Freedom Station by OSSA's Life Sciences Division and its Microgravity Science and Applications Division.

Cressy, Philip J.↗
NASA NTRS1992

Selected OAST/OSSA space experiment activities in support of Space Station Freedom

The Space Experiments Division at NASA Lewis Research Center is developing technology and science space experiments for the Office of Aeronautics and Space Technology (OAST) and the Office of Space Sciences and Applications (OSSA). Selected precursor experiments and technology development activities supporting the Space Station Freedom (SSF) are presented. The Tank Pressure Control Experiment (TPCE) is an OAST-funded cryogenic fluid dynamics experiment, the objective of which is to determine the effectiveness of jet mixing as a means of equilibrating fluid temperatures and controlling tank pressures, thereby permitting the design of lighter cryogenic tanks. The information from experiments such as this will be utilized in the design and operation of on board cryogenic storage for programs such as SSF. The Thermal Energy Storage Flight Project (TES) is an OAST-funded thermal management experiment involving phase change materials for thermal energy storage. The objective of this project is to develop and fly in-space experiments to characterize void shape and location in phase change materials used in a thermal energy storage configuration representative of an advanced solar dynamic system design. The information from experiments such as this will be utilized in the design of future solar dynamic power systems. The Solar Array Module Plasma Interaction Experiment (SAMPIE) is an OAST-funded experiment to determine the environmental effects of the low earth orbit (LEO) space plasma environment on state-of-the-art solar cell modules biased to high potentials relative to the plasma. Future spacecraft designs and structures will push the operating limits of solar cell arrays and other high voltage systems. SAMPIE will provide key information necessary for optimum module design and construction. The Vibration Isolation Technology (VIT) Advanced Technology Development effort is funded by OSSA to provide technology necessary to maintain a stable microgravity environment for sensitive payloads on board spacecraft. The proof of concept will be demonstrated by laboratory tests and in low-gravity aircraft flights. VIT is expected to be utilized by many SSF microgravity science payloads. The Space Acceleration Measurement System (SAMS) is an OSSA-funded instrument to measure the microgravity acceleration environment for OSSA payloads on the shuttle and SSF.

Delombard, Richard↗
NASA NTRS1992

Materials dispersion and biodynamics project research

The Materials Dispersion and Biodynamics Project (MDBP) focuses on dispersion and mixing of various biological materials and the dynamics of cell-to-cell communication and intracellular molecular trafficking in microgravity. Research activities encompass biomedical applications, basic cell biology, biotechnology (products from cells), protein crystal development, ecological life support systems (involving algae and bacteria), drug delivery (microencapsulation), biofilm deposition by living organisms, and hardware development to support living cells on Space Station Freedom (SSF). Project goals are to expand the existing microgravity science database through experiments on sounding rockets, the Shuttle, and COMET program orbiters and to evolve,through current database acquisition and feasibility testing, to more mature and larger-scale commercial operations on SSF. Maximized utilization of SSF for these science applications will mean that service companies will have a role in providing equipment for use by a number of different customers. An example of a potential forerunner of such a service for SSF is the Materials Dispersion Apparatus (MDA) 'mini lab' of Instrumentation Technology Associates, Inc. (ITA) in use on the Shuttle for the Commercial MDAITA Experiments (CMIX) Project. The MDA wells provide the capability for a number of investigators to perform mixing and bioprocessing experiments in space. In the area of human adaptation to microgravity, a significant database has been obtained over the past three decades. Some low-g effects are similar to Earth-based disorders (anemia, osteoporosis, neuromuscular diseases, and immune system disorders). As new information targets potential profit-making processes, services and products from microgravity, commercial space ventures are expected to expand accordingly. Cooperative CCDS research in the above mentioned areas is essential for maturing SSF biotechnology and to ensure U.S. leadership in space technology. Currently, the MDBP conducts collaborative research with investigators at the Rockefeller University, National Cancer Institute, and the Universities of California, Arizona, and Alabama in Birmingham. The growing database from these collaborations provides fundamental information applicable to development of cell products, manipulation of immune cell response, bone cell growth and mineralization, and other processes altered by low-gravity. Contacts with biotechnology and biopharmaceutical companies are being increased to reach uninformed potential SSF users, provide access through the CMDS to interested users for feasibility studies, and to continue active involvement of current participants. We encourage and actively seek participation of private sector companies, and university and government researchers interested in biopharmaceuticals, hardware development and fundamental research in microgravity.

Lewis, Marian L.↗
NASA NTRS1992

Space Station Furnace Facility. Volume 2: Summary of technical reports

The Space Station Furnace Facility (SSFF) is a modular facility for materials research in the microgravity environment of the Space Station Freedom (SSF). The SSFF is designed for crystal growth and solidification research in the fields of electronic and photonic materials, metals and alloys, and glasses and ceramics, and will allow for experimental determination of the role of gravitational forces in the solidification process. The facility will provide a capability for basic scientific research and will evaluate the commercial viability of low-gravity processing of selected technologically important materials. In order to accommodate the furnace modules with the resources required to operate, SSFF developed a design that meets the needs of the wide range of furnaces that are planned for the SSFF. The system design is divided into subsystems which provide the functions of interfacing to the SSF services, conditioning and control for furnace module use, providing the controlled services to the furnace modules, and interfacing to and acquiring data from the furnace modules. The subsystems, described in detail, are as follows: Power Conditioning and Distribution Subsystem; Data Management Subsystem; Software; Gas Distribution Subsystem; Thermal Control Subsystem; and Mechanical Structures Subsystem.

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NASA NTRS1992

The sensitivity of a non-isothermal liquid bridge to residual acceleration

An examination is conducted of the steady and unsteady behavior of isothermal and nonisothermal liquid bridge systems under both normal and low-gravity conditions, recasting the full nonlinear equations in terms of a stream-function vorticity formulation in conjunction a nonorthogonal coordinate transformation. For the cases examined, the shape of the bridge is more sensitive to typical spacecraft accelerations than the buoyancy-driven flow. The effect of thermocapillary flow on the surface shape is found to be small, for the range of capillary and Reynolds numbers considered.

Alexander, J. I. D.↗
NASA NTRS1993

Neurophysiological study on visuo-vestibular control of posture and movement in fish during adaptation to weightlessness

We can stand upright and walk smoothly without paying any particular attention to it. This is because we have established in ourselves an integration center that controls our body subconsciously in response to input from eyes, muscles, joints, foot soles, and also from the gravity sensor in the inner ear (the otolith organ). It has been shown that the cerebellum plays an important role for the establishment of the integration center and that the control pattern is comparable to that of a highly sophisticated computer system. The programming for the control, however, may well be acquired for the 1-g ground condition and does not cover the 0-g in space. Although each of the above organs function as it does on the ground, the signal pattern sent to the center must be different under 0-g and, in addition, complementary signals from the otolith organ are missing, leading to confusion in the integration center and causing a variety of symptoms similar to those of car-sickness or sea-sickness. After exposure to microgravity an immediate process of re-programming will begin and be completed in 2-4 days. There is strong supporting evidence for this sensory conflict theory as an explanation for space motion sickness (SMS) episodes. Fish were selected as test organisms for this investigation because they swim around freely in three dimensions and have well-developed organs for vision and gravity detection. They also have an innate nature to orient their back toward a light source. Actually, on the ground, the fish tilts its vertical axis toward the light when illuminated laterally, and the tilt angle is a function of the intensity of light and the magnitude of gravity, while its posture is completely light-dependent in the low-gravity environment produced by aircraft parabolic flight or when the otolith organs are removed. This implies that fish posture is entirely under visual and otolithic control. In this case, the cerebellum will also contribute to the control. In the space shuttle experiment, two fish (one with otolith-removed and the other with intact otoliths) are onboard for 7 days. The arrangement of the experiment is shown. Lamps illuminate each fish alternately from different directions at a duration of 20 seconds for 10 minutes totally, twice a day. The video images and the brain waves from the cerebellum are analyzed later. If the sensory conflict theory is acceptable, then the confusion at the onset and the following recovery process will be manifested both in the light-dependent behavior and also in the cerebellar activity. In addition, there should be some variation in response between the two fish. Even if the results are positive in the present fish experiment, they would not be extensive enough to allow us to understand the complete mechanisms of SMS. However, what is currently needed is a collection of evidence based on animal experiments on which to base future investigations. Countermeasures for SMS are mandatory since SMS-induced vomiting occurring within a space suit could be fatal for a crew member during extravehicular activities. We expect that countermeasures will be developed before the space station era starts, and that the results of these studies will be applied to improving human welfare.

Mori, Shigeo↗