Flat plate thermoelectric solar cells - Manufacturing process and life testing.
Manufacturing process and life testing of bismuth telluride alloy based flat plate thermoelectric solar cells for near earth orbits
SOLAR CELL↗
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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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Evaluation of a SET VIII thermionic generator.
SET VIII Thermionic generator, evaluating operational and long term performance characteristics for space applications
THERMIONIC CONVERSION SYSTEM↗
An assembler for the MOS Technology 6502 microprocessor as implemented in jolt (TM) and KIM-1 (TM)
Design of low-cost, microcomputer-based navigation receivers, and the assembler are described. The development of computer software for microprocessors is materially aided by the assembler program using mnemonic variable names. The flexibility of the environment provided by the IBM's Virtual Machine Facility and the Conversational Monitor System, make possible the convenient assembler access. The implementation of the assembler for the microprocessor chip serves a part of the present need and forms a model for support of other microprocessors.
Lilley, R. W.↗
Performance and safety aspects of the XV-15 tilt rotor research aircraft
Aircraft performance is presented illustrating the flexibility and capability of the XV-15 to conduct its planned proof-of-concept flight research in the areas of dynamics, stability and control, and aerodynamics. Additionally, the aircraft will demonstrate mission-type performance typical of future operational aircraft. The aircraft design is described and discussed with emphasis on the safety and fail-operate features of the aircraft and its systems. Two or more levels of redundancy are provided in the dc and ac electrical systems, hydraulics, conversion, flaps, landing gear extension, SCAS, and force-feel. RPM is maintained by a hydro-electrical blade pitch governor that consists of a primary and standby governor with a cockpit wheel control for manual backup. The two engines are interconnected for operation on a single engine. In the event of total loss of power, the aircraft can enter autorotation starting from the airplane as well as the helicopter mode of flight.
Wernicke, K. G.↗
Annual technical report, fiscal year 1979. Volume 1: Executive summary
Accomplishments of the Point-Focusing Distributed Receiver Technology project are presented. The following aspects of the project are discussed: information dissemination, concentrator development, receiver and heat transport network development, power conversion, manufacturing, systems engineering, and tests and evaluations.
Lucas, J. W.↗
Care, feeding, and use of charge-coupled device /CCD/ imagers at Palomar observatory
The paper describes the optical, mechanical, and electronic properties of the TI and RCA CCDs which have been applied to two-dimensional photometry and spectroscopy at Palomar. The drive, processing, and recording techniques are also discussed, and consideration is given to a focal conversion optical system, the Prime Focus Universal Extragalactic Instrument (PFUEI), which is used to more optimally match the Hale 5 meter plate scale. Calibration and data analysis are also examined.
Gunn, J. E.↗
Printed Circuit Converts RF Energy to dc Power
Ultra-light-weight, large area, antenna/rectifier has 85 percent conversion efficiency. System consists of large number of repetitive circuits called "rectenna elements." Each element produces 2 W of power, comprises half-wave dipole, input filter, and Schottky barrier dipole. Two-wire microwave transmission lines act as dc power collecting buses.
Triner, J.↗
Oxidant system improvements for MHD energy conversion and industrial processes
Previously cited in issue 05, p. 686, Accession no. A83-16735
Juhasz, A. J.↗
Advanced operator/system interface concepts for the Space Station
Concepts and data developed as part of the Preliminary Space Station Automation and Robotics Plan are reviewed as well as candidate selection criteria, technology assessments, and preliminary candidate recommendations. A need for development of advanced operator/systems interface (OSI) concepts to support future Space Station automation and robotics applications is identified. Four candidate applications, illustrating the potential benefits of an advanced OSI, are described. These include: (1) a conversational OSI system, (2) a laboratory experiment manipulator system, (3) a module safety advisor, and (4) an integrated maintenance/training system. These specific automation and robotics applications are expected to occur relatively early in the growth of the Space Station and to provide significant commercial and station benefits throughout the life of the station.
Case, C. M.↗
Free-Piston Stirling Engines
Engines promise cost-effective solar-power generation. Report describes two concepts for Stirling-engine systems for conversion of solar heat to electrical energy. Recognized most promising technologies for meeting U.S. Department of Energy goals for performance and cost for terrestrial electrical-energy sources.
Shaltens, Richard K.↗
Frequency-Domain Signal Processor For Laser Velocimeter
Dynamic range and accuracy increased. New signal processor for laser-velocimeter (LV) applications overcomes major limitations of present signal processors. System requires no input-signal conditioning other than that provided by amplifiers; it operates in instantaneous mode at signal levels from bursts containing as few as 150 photons down to photon-resolved regime in averaging mode. Digital value of signal-burst frequency sent to external computer system for conversion to value of absolute frequency. Residual turbulence intensity 0.2 percent, with little dependence on signal-to-noise ratio.
Meyers, James F.↗
Power and Efficiency Optimized in Traveling-Wave Tubes Over a Broad Frequency Bandwidth
A traveling-wave tube (TWT) is an electron beam device that is used to amplify electromagnetic communication waves at radio and microwave frequencies. TWT's are critical components in deep space probes, communication satellites, and high-power radar systems. Power conversion efficiency is of paramount importance for TWT's employed in deep space probes and communication satellites. A previous effort was very successful in increasing efficiency and power at a single frequency (ref. 1). Such an algorithm is sufficient for narrow bandwidth designs, but for optimal designs in applications that require high radiofrequency power over a wide bandwidth, such as high-density communications or high-resolution radar, the variation of the circuit response with respect to frequency must be considered. This work at the NASA Glenn Research Center is the first to develop techniques for optimizing TWT efficiency and output power over a broad frequency bandwidth (ref. 2). The techniques are based on simulated annealing, which has the advantage over conventional optimization techniques in that it enables the best possible solution to be obtained (ref. 3). Two new broadband simulated annealing algorithms were developed that optimize (1) minimum saturated power efficiency over a frequency bandwidth and (2) simultaneous bandwidth and minimum power efficiency over the frequency band with constant input power. The algorithms were incorporated into the NASA coupled-cavity TWT computer model (ref. 4) and used to design optimal phase velocity tapers using the 59- to 64-GHz Hughes 961HA coupled-cavity TWT as a baseline model. In comparison to the baseline design, the computational results of the first broad-band design algorithm show an improvement of 73.9 percent in minimum saturated efficiency (see the top graph). The second broadband design algorithm (see the bottom graph) improves minimum radiofrequency efficiency with constant input power drive by a factor of 2.7 at the high band edge (64 GHz) and increases simultaneous bandwidth by 500 MHz.
Wilson, Jeffrey D.↗
Novel Thermal Powered Technology for UUV Persistent Surveillance
Buoyancy Generation: Various technology attempts include melting a wax, which pushes directly against a piston (U.S. Patent 5,291,847) or against a bladder (Webb Research), using ammonia or Freon 21 (U.S. Patent 5,303,552), and using solar heat to expand an oil (www.space.com, April, 10, 2002). All these heat-activated buoyancy control designs have thus far proved impractical and have ultimately failed during repeated cycling in ocean testing. JPL has demonstrated fully reversible 10 C encapsulated wax phase change, which can be used to change buoyancy without electrical hydraulic pumps. This technique has greatly improved heat transfer and much better reversibility than previous designs. Power Generation: Ocean Thermal Energy Conversion (OTEC) systems have been designed that transfer deep, cold sea water to the surface to generate electricity using turbine cycles with ammonia or water as the working fluid. JPL has designed several UUV systems: 1) Using a propeller water turbine to generate power on a gliding submersible; 2) Employing a compact CO2 turbine cycle powered by moving through thermoclines; and 3) Using melted wax to directly produce power through a piston-geared generator.
submersible↗
High Performance Low Cost Power Conditioning Subsystems Using Smart Power/ Power Integrated Circuits in Photovoltaic Power Systems
New technologies like Smart Power, and Power Integrated Circuits are the wave of the future in providing high performance low cost power conditioning subsystem (PCS)in small to large power applications. This paper discusses circuit designs using these devices that are suitable for PCS in photovoltaic and other industrial applications such as electrical appliances, instrumentation, AC motor drives, battery chargers, automobiles, telecommunications, UPS, and switch mode power supplies. It examines the cost of high volume production and current technological barriers asociated with the development of these technologies.
smart↗
A novel system for the sequestration and conversion of carbon dioxide to useful products using stable metal oxide catalysts
Explore the source record for details and available documents.
01 COAL, LIGNITE, AND PEAT↗
Quantitative Analysis of Spectral Impacts on Silicon Photodiode Radiometers
Inexpensive broadband pyranometers with silicon photodiode detectors have a non-uniform spectral response over the spectral range of 300-1100 nm. The response region includes only about 70% to 75% of the total energy in the terrestrial solar spectral distribution from 300 nm to 4000 nm. The solar spectrum constantly changes with solar position and atmospheric conditions. Relative spectral distributions of diffuse hemispherical irradiance sky radiation and total global hemispherical irradiance are drastically different. This analysis convolves a typical photodiode response with SMARTS 2.9.5 spectral model spectra for different sites and atmospheric conditions. Differences in solar component spectra lead to differences on the order of 2% in global hemispherical and 5% or more in diffuse hemispherical irradiances from silicon radiometers. The result is that errors of more than 7% can occur in the computation of direct normal irradiance from global hemispherical irradiance and diffuse hemispherical irradiance using these radiometers.
14 SOLAR ENERGY↗
Pyroprocessing of Oxidized Sodium-Bonded Fast Reactor Fuel -- an Experimental Study of Treatment Options for Degraded EBR-II Fuel
An experimental study was conducted to assess pyrochemical treatment options for degraded EBR-II fuel. As oxidized material, the degraded fuel would need to be converted back to metal to enable electrorefining within an existing electrometallurgical treatment process. A lithium-based electrolytic reduction process was studied to assess the efficacy of converting oxide materials to metal with a particular focus on the impact of zirconium oxide and sodium oxide on this process. Bench-scale electrolytic reduction experiments were performed in LiCl-Li2O at 650 °C with combinations of manganese oxide (used as a surrogate for uranium oxide), zirconium oxide, and sodium oxide. The experimental study illustrated how zirconium oxide and sodium oxide present different challenges to a lithium-based electrolytic reduction system for conversion of select metal oxides to metal.
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
Model, Design, and Control for Power Conversion in Wave Energy Converter System
Wave energy, if all been harvested along the U.S. coastline, can power around 65% of the energy consumption in U.S.. Comparing to other renewable energy sources like solar or wind, ocean wave can provide up to 90% of steady uptime. With the high energy density (2-3 kW/m 2 ), it can produce more energy with the same amount of installation area comparing to the energy density of wind turbine (0.6 kW/m 2 ) and solar panel(0.2 kW/m 2 ). The predictability of wave provides advantages like planning installation, power dispatching, and maintenance activities. Although with all these advantages, wave energy converter system is still in the research stage due to its high system cost per electricity production. One of the challenges that need to be solved is the irregularity from the wave motion that leads to high instantaneous peak power into the wave energy converter, which usually reaches up to 10 - 20 times of the average power. The high peak power will not only bring high mechanical/electrical stress but also result in an overrating design of the components in the system. Another obstacle that prevents the wave energy system from moving forward is the high testing cost from the validations in wave-energy-test sites or tank-test sites. A high-fidelity multi-disciplinary system model, including hydrodynamics, mechanical dynamics, electromagnetics, and power electronics, is needed to predict the behavior of the system and reduce the cost of design validation.
16 TIDAL AND WAVE POWER↗