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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 487 records · Page 27

Cryogenic wind tunnels for high Reynolds number testing

This paper begins with a brief review of cryogenic wind tunnels and their use for high Reynolds number testing. Emphasis is on operational experience and recent aerodynamic tesing in the NASA Langley 0.3-m Transonic Cryogenic Tunnel (TCT). Specific area covered in this paper include development of test techniques and aerodynamic testing in cryogenic tunnels. Details of research experience in developing model construction techniques, including airfoils as thin as 5 percent, are given. The use of advanced testing techniques to increase the value of cryogenic tunnels to the research community is recommended. These include adaptive wall test sections using solid but flexible top and bottom walls and magnetic suspension and balance systems.

Kilgore, Robert A.↗

U.S. Laboratory Module - Its capabilities and accommodations to support user payloads

The U.S. Laboratory Module of the Space Station is discussed, focusing on user accommodations. The configuration and subsystems capabilities of the module are described, including the power, thermal, environmental control, and data management subsystems, the vacuum system, process materials management, and laboratory support equipment. The experimental facilities included in the laboratory are listed. The experiment operations planned for the laboratory are examined and compared with the experimental activities in other manned space laboratories.

Powell, Luther E.↗

Communication as group process mediator of aircrew performance

Considering recent operating experience as a group-level input factor, aspects of the communication process between crewmembers (captain and first officer) were explored as a possible mediator to performance. Communication patterns were defined by a speech-act typology adapted for the flight-deck setting and distinguished crews that had previously flown together (FT) from those that had not flown together (NFT). A more open communication channel and greater first officer participation in task-related topics was shown by FT crews, while NFT crews engaged in more nontask discourse.

Kanki, Barbara G.↗

Construction of large space power facilities

Construction was an important facet of the Satellite Power System studies in the late 1970s. Satellite servicing and assembly of the Space Station Freedom are addressing many of the critical issues in construction of large space systems. Design for assembly, capability of construction equipment and interaction with the launch system influence configuration development. The extravehicular capabilities of space-suited crew and remote operating systems like the Flight Telerobotic Servicer will provide an operational experience base for development of future large space power facilities. Economics success may well depend on early consideration of construction requirements and capabilities.

Jenkins, Lyle M.↗

A review of test results on parabolic dish solar thermal power modules with dish-mounted Rankine engines and for production of process steam

This paper presents results of development testing of various solar thermal parabolic dish modules and assemblies. Most of the tests were at modules and assemblies that used a dish-mounted, organic Rankine cycle turbine for production of electric power. Some tests were also run on equipment for production of process steam or for production of electricity using dish-mounted reciprocating steam engines. These tests indicate that early modules achieve efficiencies of about 18 percent in converting sunlight to electricity (excluding the inverter but including parasitics). A number of malfunctions occurred. The performance measurements, as well as the malfunctions and other operating experience, provided information that should be of value in developing systems with improved performance and reduced maintenance.

Jaffe, Leonard D.↗

Model 0A wind turbine generator FMEA

The results of Failure Modes and Effects Analysis (FMEA) conducted for the Wind Turbine Generators are presented. The FMEA was performed for the functional modes of each system, subsystem, or component. The single-point failures were eliminated for most of the systems. The blade system was the only exception. The qualitative probability of a blade separating was estimated at level D-remote. Many changes were made to the hardware as a result of this analysis. The most significant change was the addition of the safety system. Operational experience and need to improve machine availability have resulted in subsequent changes to the various systems which are also reflected in this FMEA.

Klein, William E.↗

Analysis of dewar and transfer line cooldown in Superfluid Helium On-Orbit Transfer Flight Experiment (SHOOT)

The Superfluid Helium On-Orbit Transfer Flight Experiment (SHOOT) is designed to demonstrate the techniques and components required for orbital superfluid (He II) replenishment of observatories and satellites. One of the tasks planned in the experiment is to cool a warm cryogen tank and a warm transfer line to liquid helium temperature. A math model, based on single-phase vapor flow heat transfer, has been developed to predict the cooldown time, component temperature histories, and helium consumption rate, for various initial conditions of the components and for the thermomechanical pump heater powers of 2 W and 0.5 W. This paper discusses the model and the analytical results, which can be used for planning the experiment operations and determining the pump heater power required for the cooldown operation.

Ng, Y. S.↗

A user-oriented synthetic workload generator

A user oriented synthetic workload generator that simulates users' file access behavior based on real workload characterization is described. The model for this workload generator is user oriented and job specific, represents file I/O operations at the system call level, allows general distributions for the usage measures, and assumes independence in the file I/O operation stream. The workload generator consists of three parts which handle specification of distributions, creation of an initial file system, and selection and execution of file I/O operations. Experiments on SUN NFS are shown to demonstrate the usage of the workload generator.

Kao, Wei-Lun↗

Model-OA wind turbine generator - Failure modes and effects analysis

The results failure modes and effects analysis (FMEA) conducted for wind-turbine generators are presented. The FMEA was performed for the functional modes of each system, subsystem, or component. The single-point failures were eliminated for most of the systems. The blade system was the only exception. The qualitative probability of a blade separating was estimated at level D-remote. Many changes were made to the hardware as a result of this analysis. The most significant change was the addition of the safety system. Operational experience and need to improve machine availability have resulted in subsequent changes to the various systems, which are also reflected in this FMEA.

Klein, William E.↗

Onboard System Processes SAR Data

Aircraft Flight Correlator (AFC) computing system, mounted with AIRSAR synthetic-aperture-radar (SAR) system, supplements recording and postflight analysis, processing portion of data in real or nearly real time to provide imagery for rapid evaluation. Facilitates diagnosis of SAR equipment or adjustment of parameters of experiment. Operates in two modes: "quick-look" mode, data processed in 10 minutes into high-resolution image; and "real-time" mode, data processed in real time to reduced resolution. Also used as aid to navigation.

Carande, Richard E.↗

Low Temperature Environment Operations of Turboengines (Design and User's Problems)

The author summarizes and links together a number of papers that were presented at the Propulsion and Energetics (PEP) symposium on low temperature environment operation of turbojet engines that was held October 8 to 12, 1990. Topics covered include operational experience of ice ingestion in the turboprop engine in the 2,000 hp class, icing on helicopter turbo engines, icing test facilities, ice relevant cloud physical parameters, and low temperature and fuel problems.

R Jacques↗

Magellan mission planning and orbital operations

The goal of NASA's Magellan mission is to understand the geological and geophysical processes that have shaped the planet Venus. Through synthetic aperture radar, radiometric, altimetric, and gravity measurements, the scientific community hopes to improve its knowledge of the planet's topography and internal mass distribution. This paper provides an overview of the Magellan mission; describes the spacecraft sequence software design, development, and test; addresses the nominal operational flow of stored sequence design and generation; briefly describes the ground processing of engineering telemetry and imaging data; and then summarizes the Magellan operational experience with non-routine behavior of the spacecraft during the cruise and mapping portions of the prime mission.

Venus↗

Summary of astronaut inputs on automation and robotics for Space Station Freedom

Astronauts and payload specialists present specific recommendations in the form of an overview that relate to the use of automation and robotics on the Space Station Freedom. The inputs are based on on-orbit operations experience, time requirements for crews, and similar crew-specific knowledge that address the impacts of automation and robotics on productivity. Interview techniques and specific questionnaire results are listed, and the majority of the responses indicate that incorporating automation and robotics to some extent and with human backup can improve productivity. Specific support is found for the use of advanced automation and EVA robotics on the Space Station Freedom and for the use of advanced automation on ground-based stations. Ground-based control of in-flight robotics is required, and Space Station activities and crew tasks should be analyzed to assess the systems engineering approach for incorporating automation and robotics.

Weeks, David J.↗

Current Technology for Thermal Protection Systems

Interest in thermal protection systems for high-speed vehicles is increasing because of the stringent requirements of such new projects as the Space Exploration Initiative, the National Aero-Space Plane, and the High-Speed Civil Transport, as well as the needs for improved capabilities in existing thermal protection systems in the Space Shuttle and in turbojet engines. This selection of 13 papers from NASA and industry summarizes the history and operational experience of thermal protection systems utilized in the national space program to date, and also covers recent development efforts in thermal insulation, refractory materials and coatings, actively cooled structures, and two-phase thermal control systems.

Scotti, Stephen J.↗

Program overview: 1991 flight test objectives

The topics are presented in viewgraph form and include the following: the Joint NASA/FAA Airborne Wind Shear Detection and Avoidance Program; the windshear problem; NASA/FAA Wind Shear Program objectives; program elements; Wind Shear Program roadmap; airborne wind shear sensors; 1991 wind shear flight experiments; operative wind shear detection systems; research aircraft sensor installations; and 1991 test results.

Bowles, Roland L.↗

Capacity fade in nickel cadmium and nickel hydrogen cells

Research and operational experience with capacity fade in nickel cadmium and nickel hydrogen cells are summarized in outline form. The theoretical causes of capacity fade are reviewed and the role of cell storage, positive electrodes, and cobalt additives are addressed. Three examples of observed capacity fade are discussed: INTELSAT 5, INTELSAT 6, and an Explorer platform. Finally, prevention and recovery methods are addressed and the current status of Eagle Picher/Hughes research is discussed.

Edgar, Tim↗

NASA PPO microgravity projects support

Work progress is reported in brief. A summary of this information is provided below. An in-depth study was performed to evaluate a new European designed Borack Freezer/Cooler for possible shuttle middeck flight to support advanced protein crystal growth (APCG) experimentation. A statement of work was prepared for the design and development of a glovebox for proposed flight in the shuttle middeck. Work was also initiated to perform an analysis of low-g accelerometer data relative to Fluid Experiment System (FES) experiment options on the IML-1 mission. This work was undertaken in an effort to determine if abnormally low-g accelerations during the mission were responsible for anomalies which occurred during FES/Triglycine Sulfate (TGS) experiment operations. A comprehensive review was made on a revised edition of the Geophysical Fluid Flow Cell (GFFC) Operations and Maintenance (O&M) Manual.

Smith, Janice F.↗

Low-frequency vibration environment for five Shuttle missions

The Microgravity Science and Applications Division's (MSAD) program to record and analyze the Shuttle's vibration environment is reviewed. This program provides microgravity science investigators with time and frequency analyses of the acceleration environment during their experiments' operation. Information is also provided for future investigators on the expected Shuttle vibration environment. As background, the two major elements of the program are discussed, the Space Acceleration Measurement System (SAMS) and the Acceleration Characterization and Analysis Project (ACAP). A comparison of the acceleration measurements from five Shuttle missions is discussed.

Baugher, George R.↗