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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 235 records · Page 13

STS-42 Space Shuttle mission report

The STS-42 Space Shuttle Program Mission Report contains a summary of the vehicle subsystem operations during the forty-fifth flight of the Space Shuttle Program and the fourteenth flight of the Orbiter vehicle Discovery (OV-103). In addition to the Discovery vehicle, the flight vehicle consisted of the following: an External Tank (ET) designated as ET-52 (LWT-45); three Space Shuttle main engines (SSME's), which were serial numbers 2026, 2022, and 2027 in positions 1, 2, and 3, respectively; and two Solid Rocket Boosters (SRB's) designated as BI-048. The lightweight redesigned Solid Rocket Motors (RSRM's) installed in each one of the SRB's were designated as 360L020A for the left SRM and 360Q020B for the right SRM. The primary objective of the STS-42 mission was to complete the objectives of the first International Microgravity Laboratory (IML-1). Secondary objectives were to perform all operations necessary to support the requirements of the following: Gelation of Sols: Applied Microgravity Research (GOSAMR); Student Experiment 81-09 (Convection in Zero Gravity); Student Experiment 83-02 (Capillary Rise of Liquid Through Granular Porous Media); the Investigation into Polymer Membrane Processing (IPMP); the Radiation Monitoring Equipment-3 (RME-3); and Get-Away Special (GAS) payloads carried on the GAS Beam Assembly.

Fricke, Robert W.↗

New findings and instrumentation from the NASA Lewis Microgravity Facility

The study of fundamental combustion and fluid physics phenomena in microgravity enables a new range of experiments to be performed since buoyancy-type flows are nearly eliminated, normally obscured forces and flows may be isolated, gravitational settling or sedimentation is nearly eliminated, and larger time or length scales in experiments become permissible. Some new phenomena found through ground-based microgravity research at NASA facilities is reviewed along with the instrumentation and drop tower facilities used in the research. Experiments are described in the areas of premixed gas combustion, droplet combustion, particle cloud combustion, liquid reorientation, and two-phase flow patterns. Future plans for instrumentation development are also outlined.

Ross, Howard D.↗

Defying Gravity

This video examines microgravity research that is ongoing at LeRC. The video details the development of the Multiple Axis Space Test and its use in training the Mercury 7 astronauts. The LeRC drop tower is discussed, and a comparison is made between research being done at LeRC and rides anyone can experience at the nearby Cedar Point Amusement Park.

Source record↗

An adaptable product for material processing and life science missions

The Experiment Control System II (ECS-II) is designed to make available to the microgravity research community the same tools and mode of automated experimentation that their ground-based counterparts have enjoyed for the last two decades. The design goal was accomplished by combining commercial automation tools familiar to the experimenter community with system control components that interface with the on-orbit platform in a distributed architecture. The architecture insulates the tools necessary for managing a payload. By using commercial software and hardware components whenever possible, development costs were greatly reduced when compared to traditional space development projects. Using commercial-off-the-shelf (COTS) components also improved the usability documentation, and reducing the need for training of the system by providing familiar user interfaces, providing a wealth of readily available documentation, and reducing the need for training on system-specific details. The modularity of the distributed architecture makes it very amenable for modification to different on-orbit experiments requiring robotics-based automation.

Wassick, Gregory↗

Non-Coalescence Effects in Microgravity

Non-coalescence of two bodies of the same liquid and the suppression of contact between liquid drops and solid surfaces is being studied through a pair of parallel investigations being conducted at the Georgia Institute of Technology and the Microgravity Research and Support (MARS) Center in Naples, Italy. Both non-coalescence and contact suppression are achieved by exploiting the mechanism of thermocapillary convection to drive a lubricating film of surrounding gas (air) into the space between the two liquid free surfaces (non-coalescence) or between the drop free surface and the solid (contact suppression). Experiments performed to date include flow visualization experiments in both axisymmetric and (nearly) two-dimensional geometries and quantitative measurements of film thickness in the contact-suppression case in both geometries.

Neitzel, G. Paul↗

Experimental Modification of Rat Pituitary Growth Hormone Cell Function During and After Spaceflight

Space-flown rats show a number of flight-induced changes in the structure and function of pituitary Growth Hormone (GH) cells after in vitro postflight testing. To evaluate the possible effects of microgravity on GH cells themselves, freshly dispersed rat anterior pituitary gland cells were seeded into vials containing serum +/- 1 micron HydroCortisone (HC) before flight. Five different cell preparations were used: the entire mixed-cell population of various hormone-producing cell types, cells of density less than 1.071 g/sq cm (band 1), cells of density greater than 1.071 g/sq cm (band 2), and cells prepared from either the dorsal or ventral part of the gland. Relative to ground control samples, bioactive GH released from dense cells during flight was reduced in HC-free medium but was increased in HC-containing medium. Band I and mixed cells usually showed opposite HC-dependent responses. Release of bioactive GH from ventral flight cells was lower; postflight responses to GH-releasing hormone challenge were reduced, and the cytoplasmic area occupied by GH in the dense cells was greater. Collectively, the data show that the chemistry and cellular makeup of the culture system modifies the response of GH cells to microgravity. As such, these cells offer a system to identify gravisensing mechanisms in secretory cells in future microgravity research.

Hymer, W. C.↗

Experimental Modification of Rat Pituitary Prolactin Cell Function During and After Spaceflight

Experimental modification of rat pituitary prolactin cell function during and after spaceflight. This study was done to evaluate the effects of microgravity on prolactin (PRL) cells of the male rat pituitary gland. We used the identical passive closed-vial cell culture system that was described for the culture of growth hormone cells (W C. Hymer, R. E. Grindeland, T. Salada, P. Nye, E. Grossman, and R Lane). After an 8-day spaceflight, all flight media (containing released PRL), as well as extracts (containing intracellular PRL), contained significantly lower amounts of immunoreactive PRL than their corresponding ground control samples. On the other hand, these same samples, when assessed for their biological activities by two different in vitro lymphocyte assays, yielded disparate results that may reflect posttranslational modifications to the hormone molecule. Other data showed that: (1) the apparent molecular weights of released PRL molecules were not altered by microgravity; but (2) the region from which the PRL cells came (dorsal or ventral) made a significant difference in the amount and activity of PRL released from the flight cells. Because there is much current interest in the role that PRL may play in the regulation of the immune system and because changes in both cellular and humoral immunity accompany spaceflight, this study could help define future microgravity research in this area.

Hymer, W. C.↗

Non-Coalescence Effects in Microgravity

Non-coalescence of two bodies of the same liquid and the suppression of contact between liquid drops and solid surfaces is being studied through a pair of parallel investigations being conducted at the Georgia Institute of Technology and the Microgravity Research and Support (MARS) Center in Naples, Italy. Both non-coalescence and contact suppression are achieved by exploiting the mechanism of thermocapillary convection to drive a lubricating film of surrounding gas (air) into the space between the two liquid free surfaces (non-coalescence) or between the drop free surface and the solid (contact suppression). Earlier experiments performed included flow-visualization experiments in both axisymmetric and (nearly) two-dimensional geometries and quantitative measurements of film thickness in the contact-suppression case in both geometries. Work done in the second year has focused on obtaining quantitative results relating to the effects of variable air pressure, development of analytical and numerical models of non-coalescing droplets and to pursuing potential applications of these self-lubricated systems.

Neitzel, G. Paul↗

Fluids and Combustion Facility-Combustion Integrated Rack

This paper describes in detail the concept of performing Combustion microgravity experiments in the Combustion Integrated Rack (CIR) of the Fluids and Combustion Facility (FCF) on the International Space Station (ISS). The extended duration microgravity environment of the ISS will enable microgravity research to enter into a new era of increased scientific and technological data return. The FCF is designed to increase the amount and quality of scientific and technological data and decrease the development cost of an individual experiment relative to the era of Space Shuttle experiments. This paper also describes how the FCF will cost effectively accommodate these experiments.

Francisco, David R.↗

Human Factors Engineering at Marshall Space Flight Center

The mission of NASA Marshall Space Flight Center (MSFC) is to develop, implement, and maintain systems for space transportation and microgravity research. Factors impacting the MSFC position as a leader in advancing science and technology include: (1) heightened emphasis on safety; (2) increased interest in effective resource utilization; and (3) growing importance of employing systems and procedures that pragmatically support mission science. In light of these factors, MSFC is integrating human factors engineering (HFE) into the systems engineering process. This paper describes the HFE program, applications of HFE in MSFC projects, and the future of HFE at MSFC.

Dunn, M. C.↗

NASA's Microgravity Technology Report: Summary of Activities 1997

The purpose of the 1997 NASA Microgravity Technology Report is to update the Microgravity Research Program's technology development policy and to present and assess current technology related activities and requirements identified within its research and technology disciplines.

Woodard, Dan↗

Characterization of the Heat Extraction Capability of a Compliant, Sliding, Thermal Interface for Use in a High Temperature, Vacuum Microgravity Furnace

Much of the material science gained in microgravity research requires processing a sample in a high performance furnace. One such furnace currently being designed is the Quench Module Insert (QMI). The Principle Investigators, for whom the furnace is proposed, require high temperature gradients in their cylindrical samples to achieve the science objectives. One of the components critical to achieving high sample axial temperature gradients in the Quench Module Insert is a high performance cold zone to extract the heat from the sample. This cold zone employs a compliant, sliding thermal interface based on a Vel-Therm felt. This felt provides a conductive path between the Sample Cartridge Assembly (SCA) exterior surface and the interior surface of the water cooled chill block while allowing movement of the sample relative to the chill block. The Vel-Therm felt is composed of long polymer-based fibers affixed to a thin flexible substrate layer. The fibers are oriented perpendicular to this substrate giving the felt the appearance of a velvet fabric. The Vel-Therm felt heat extraction capability was quantified in earlier tests performed in an inert gas environment. The current activity, described in this paper, is intended to characterize the extraction capability of Vel-Therm felt in a vacuum environment similar to the QMI environment. This testing is necessary to quantify the thermal performance of the Vel-Therm felt and the sensitivity of that performance to key variables. The data derived from these tests will be incorporated into the current thermal models to improve the quality of the models and reduce uncertainty of the analytical results. In addition, the data will be used to help select the appropriate Vel-Therm felt and set proper operating limits as well as assess the performance range of the furnace. The objective of this test is to measure the heat extraction rate of the Vel-Therm felt as specified by the effective heat transfer coefficient. Therefore, the test setup was designed to force the bulk of the heat transfer through the area where the Vel-Therm felt was applied. A heat source, consisting of a ceramic heating element encased in a Copper (Cu) housing is mounted on four isolated support rods. A 6-layer molybdenum radiation shield is used to insulate against heat loss from the heater and prevent heat exchange between the hot and cold sides of the test apparatus. The Vel-Therm felt is affixed to the surface of the cold sink, a water-cooled Cu chill block. An adjustable plate supports and isolates the cold sink from above and is used to control the amount of the deflection of the Vel- Therm when in contact with the Cu heating element housing. The primary means of establishing the power being conducted through the felt is to measure the energy being transferred to the water passing through the chill block. Analysis was performed to support the assumption that the source and sink surfaces were approximately isothermal under the specific test conditions. As a check on the amount of power passing through the felt, the power supplied to the heater was also measured. Thermocouples were strategically located throughout the test apparatus for measurement purposes. A bell jar was lowered over the assembly to impose vacuum conditions. Currently, variables tested have been fiber compression and fiber type and surface temperatures (both the hot and cold side temperatures are hypothesized to be important to the performance of the Vel-Therm.) Selected runs were repeated to ensure consistency and repeatability. Results obtained thus far reveal that Vel-Therm performance is significantly degraded by fibers being exposed to high compression. It also shows that performance is somewhat negatively impacted by previous compression, thereby, raising the question of repeatability. In addition, early results show a significant dependence on temperature. A computer aided mathematical analysis of the test setup is ongoing. The results will be correlated to actual results. The correlation will examine such details as parasitic loses, conduction down the power leads and many other concerns.

Bellomy-Ezell, Jenny↗

Non-Coalescence Effects in Microgravity

Non-coalescence of two bodies of the same liquid and the suppression of contact between liquid drops and solid surfaces is being studied through a pair of parallel investigations being conducted at the Georgia Institute of Technology and the Microgravity Research and Support (MARS) Center in Naples, Italy. Both non-coalescence and contact suppression are achieved by exploiting the mechanism of thermocapillary convection to drive a lubricating film of surrounding gas (air) into the space between the two liquid free surfaces (non-coalescence) or between the drop free surface and the solid (contact suppression). Experiments performed to date include flow visualization experiments in both axisymmetric and (nearly) two-dimensional geometries and quantitative measurements of film thickness in the contact-suppression case in both geometries.

Neitzel, G. Paul↗

The Current Microgravity Materials Science Program

A description will be made of the current materials science program within the microgravity research division. This presentation will be made at a plenary session of the biennial materials Science Conference.

Gillies, Donald C.↗

The Future of New Discoveries on the International Space Station

The Materials Science program is one of the five Microgravity research disciplines in NASA's Human Exploration and Development of Space (HEDS). This research uses the low gravity environment to obtain the fundamental understanding of various phenomena effects and it's relationship to structure, processing, and properties of materials. The International Space Station (ISS) will complete the first major assembly phase within the next year thus providing the opportunity for on-orbit research and scientific utilization in early 2001. Research will become routine as the final Space Station configuration is completed. Accommodations will support a variety of Materials Science payload hardware both in the US and international partner modules. This paper addresses the current scope of the flight investigator program that will utilize the various capabilities on ISS. The type of research and classification of materials that are addressed using multiple types of flight apparatus will be explained. The various flight and ground facilities that are used to support the NASA program are described. The early utilization schedule for the materials science payloads with associated hardware will be covered. The Materials Science Research Facility and related international experiment modules serves as the foundation for this capability. The potential applications and technologies obtained from the Materials Science program are described.

Schlagheck, Ronald↗

Current Experiments in Microgravity

The Materials Science program within NASA's Microgravity Research Division will be outlined. Particular emphasis will be placed on those experiments slated for the International Space Station which pertain to high temperature materials. These include experiments designed to examine theories pertaining to solidification and pattern selection, coarsening and phase transformation.

Gillies, Donald C.↗

Convective Melting of Particles in Flow Under Microgravity Conditions

Study of melting of dispersed or packed solid particles in a fluid under gravity and microgravity conditions provides benchmark information for many engineering applications such as material processing, environmental assessment and protection and space fire protection. During such processes, packed or dispersed solid particles are interacting with fluid flow at above-melting temperatures. By unmasking the buoyancy effects in coupled flow, phase change and heat transport phenomena, a better understanding of melting rate in non-thermal equilibrium, convective conditions can be studied. A series of flight experiments were conducted onboard the NASA KC-135 Microgravity Research Airplane. The Particle Melting in Plow (PMF) module was designed to allow flow through the initially packed ice particles at controlled temperature and velocity. To achieve this, a close-loop flow system was designed. Video images were taken to record the visualization of the melting process, from which a time variation of packed particle thickness distribution at different times can be obtained by the image analysis method. The fluid temperature distribution within the melting zone is measured by thermocouples. An infrared camera was mounted from the top of the test section to record the ice-water thermal images at a given location. The results from thermal images yield local temperature variation between melting solid and liquid and local Stephan number. Typical results for a number of cases are presented. The mathematical model, describing mass, energy, and momentum balance equations for the liquid and solid phases, is presented. It is found that melting rate is influenced mainly by the ratio of Reynolds number (based on the initial particle diameter) to the Froud number, and Stephan number. At the absence of gravity, Froud number approaches zero, Reynolds number and Stephan number become dominant factors governing the melting rate. The numerically determined results are compared with the experimental ones. It is found that the discrepancy between the predicted and measured melting rate is largely due to the inaccuracy in the constitutive equations for effective thermal physical properties, such as effective thermal conductivity and diffusivity, and transport properties, such as particle interaction coefficient, and local heat transfer coefficient of particles.

Stewart, C.↗

Determination of an Optimal Commercial Data Bus Architecture for a Flight Data System

NASA/Marshall Space Flight Center (MSFC) is continually looking for methods to reduce cost and schedule while keeping the quality of work high. MSFC is NASA's lead center for space transportation and microgravity research. When supporting NASA's programs several decisions concerning the avionics system must be made. Usually many trade studies must be conducted to determine the best ways to meet the customer's requirements. When deciding the flight data system, one of the first trade studies normally conducted is the determination of the data bus architecture. The schedule, cost, reliability, and environments are some of the factors that are reviewed in the determination of the data bus architecture. Based on the studies, the data bus architecture could result in a proprietary data bus or a commercial data bus. The cost factor usually removes the proprietary data bus from consideration. The commercial data bus's range from Versa Module Eurocard (VME) to Compact PCI to STD 32 to PC 104. If cost, schedule and size are prime factors, VME is usually not considered. If the prime factors are cost, schedule, and size then Compact PCI, STD 32 and PC104 are the choices for the data bus architecture. MSFC's center director has funded a study from his discretionary fund to determine an optimal low cost commercial data bus architecture. The goal of the study is to functionally and environmentally test Compact PCI, STD 32 and PC 104 data bus architectures. This paper will summarize the results of the data bus architecture study.

Crawford, Kevin↗