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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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An aeroelastic investigation of horizontal axis wind turbines is described. The study is divided into two simpler areas; (1) the aeroelastic stability of a single blade on a rigid tower; and (2) the mechanical vibrations of the rotor system on a flexible tower. Some resulting instabilities and forced vibration behavior are described.
Noncorrosive fluid subsystem is being developed that is compatible with closed-loop solar heating and combined heating and hot water systems. The system is also to be compatible with both metallic and nonmetallic plumbing systems, and any combination of these. At least 100 gallons of each type of fluid recommended by the contractor will be delivered.
Program descriptions, flow charts, and program listings for the SIMWEST model generation program, the simulation program, the file maintenance program, and the printer plotter program are given. For Vol 2, see .
Maintaining cryogenic fluorine at a -189 C during the interplanetary cruise period to Mars is a major thermal problem. At this low temperature the heat rejection by radiation is severely limited and the allowable thermal load to the fluorine tank is less than approximately 8 watts. Previous studies generally constrain the spacecraft to an inline tank configuration which tends to maximize the fluorine tank's view and heat rejection to space. With the Inertial Upper Stage, sufficient stack height may not be available on the Shuttle for an inline tank configuration. Therefore, this study addresses the more thermally constraining side by side tank configuration.
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Volume 2 of this 2 volume report is represented. This volume contains three appendices: (1) bibliography and cross references; (2) taxonomy - proponents and sources; and (3) concept definitions.
The project areas discussed include: (1) demand and decision analysis; (2) market analysis; (3) institutional analysis; (4) social cost analysis; and (5) performance and standard analysis.
Potential concepts for near term electric utility applications were identified. The most promising ones for conceptual design were evaluated for their economic feasibility and cost benefits. The screening process resulted in selecting two coal-fired and two nuclear plants for detailed conceptual design. The coal plants utilized peaking turbines and the nuclear plants varied the feedwater extraction to change power output. It was shown that the performance and costs of even the best of these systems could not compete in near term utility applications with cycling coal plants and typical gas turbines available for peaking power. Lower electricity costs, greater flexibility of operation, and other benefits can be provided by cycling coal plants for greater than 1500 hours of peaking or by gas turbines for less than 1500 hours if oil is available and its cost does not increase significantly.
Procedures are given for using the SIMWEST program on CDC 6000 series computers. This expanded software package includes wind and/or photovoltaic systems utilizing any combination of five types of storage (pumped hydro, battery, thermal, flywheel, and pneumatic).
The computer programs for the CDC version of SIMWEST (1979 revision) are described. Macro flow charts and source code listings for each major program entity are presented.
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Anion exchange membranes used in the system serve as a charge transferring medium as well as a reactant separator and are the key enabling component in this storage technology. Each membrane formulation undergoes a series of screening tests for area-resistivity, static (non-flow) diffusion rate determination, and performance in Redox systems. The CDIL series of membranes has, by virtue of its chemical stability and high ion exchange capacity, demonstrated superior properties in the redox environment. Additional resistivity results at several acid and iron solution concentrations, iron diffusion rates, and time dependent iron fouling of the various membrane formulations are presented in comparison to past standard formulations.
Some advanced technology concepts under development for high-temperature solar thermal energy systems to achieve significant energy cost reductions and performance gains and thus promote the application of solar thermal power technology are presented. Consideration is given to the objectives, current efforts and recent test and analysis results in the development of high-temperature (950-1650 C) ceramic receivers, thermal storage module checker stoves, and the use of reversible chemical reactions to transport collected solar energy. It is pointed out that the analysis and testing of such components will accelerate the commercial deployment of solar energy.
The model of fictive ideal components is used to determine Gibbs free energies of formation of pyrope and Al2O3-enstatite from the experimental data on coexisting garnet and orthopyroxene and orthopyroxene and spinel in the temperature range 1200-1600 K. It is noted that Al2O3 forms an ideal solution with MgSiO3. These thermochemical data are found to be consistent with the Al2O3 isopleths that could be drawn using most recent experimental data and with the reversed experimental data on the garnet-spinel field boundary.
Chromium electrodes were prepared for the NASA Redox Storage System with meet the performance requirements for solar-photovoltaic, wind-turbine and electric utility applications. Gold-lead catalyzed carbon felt electrodes up tp 930 sq cm were fabricated and tested in single cells and multicell stacks for hydrogen evolution, coulombic efficiency, catalyst stability and electrochemical activity. Factors which affect the overall performance of a particular electrode include the carbon felt lot, the cleaning treatment and the gold catalyzation method. Effects of the chromium solution chemistry and impurities on charge/discharge performance are also presented.
Electrochemical and thermochemical systems are reviewed. Chemical heat pumps, end-use applications and systems studies, and storage systems and materials are also discussed.
A discrete gust model has been designed which includes an expression for the number of times per unit time thy wind exceeds a specific value. This expression, based on Rice's (1944, 1945) number-of-crossings model, assumes that the yearly mean wind speed is averaged over a period of 10 minutes to 1 (one) hour. Vertical and lateral coherence functions are the basis for a mathematical filter which isolates atmospheric disturbances of a characteristic size (e. g., those which would completely engulf a rotor). Predictions are calculated usising the given definition of cut-off frequency, then they are compared with actual data, showing that the model is reliable. The expression is provided in a format such that it may be used for engineering design calculations.
The economic advantages of solar dish collectors are evaluated and compared with other energy systems. Labor, inflation and energy deregulation are considered.