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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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To support NYPA's efforts in delivering a feasibility study to advise PANYNJ on future distributed energy resource (DER) deployments at their facilities.
Ensuring the integrity of Grade 91 (9Cr-1Mo-V) steel welds is vital for the safe and reliable operation of fossil fuel–fired and nuclear power plants. Here, this study applies an imaging technique for the ultrasonic characterization of two Grade 91 steel welds created with cold metal transfer and flux-cored arc welding processes. Ultrasonic immersion testing in the through-transmission configuration was employed to generate shear waves, which helped identify the weld metal, heat-affected zone, and base metal regions. These weld microstructures were also correlated to their ultrasonic images using metallography, ultrasonic amplitude, hardness measurements, and grain size. The findings from this study can assist practitioners in developing new nondestructive evaluation technologies, improving the inspection reliability of creep strength–enhanced ferritic steel welds by potentially identifying weld microstructure regions susceptible to creep-type failures.
TV broadcast satellite system operating with modified home receivers or special receivers, evaluating technological and cost factors
TV broadcast satellite system operating with home receivers or special receivers, evaluating technological and cost factors
The feasibility of developing a solar electric multimission spacecraft (SEMMS) is examined with emphasis on understanding the effect of solar electric propulsion elements on a spacecraft system design. The applicability of Mariner, Viking, and thermoelectric outer planet spacecraft (TOPS) technologies to postulated mission/science objectives is investigated. A Mariner/Viking-based, modular spacecraft evolves which, with minimum modifications, is capable of performing a variety of interplanetary missions, including comet and asteroid rendezvous and orbit of Mercury, Jupiter, and Saturn. An early technology-evaluation flight is recommended to minimize the risk in subsequent missions.
The Department of Transportation requested that the NASA Office of Aeronautics and Space Technology evaluate and assess the potential of several types of gas turbine engines and fuels for the on-board power and propulsion of a future heavy-duty ground transportation system. The purpose of the investigation was threefold: (1) to provide a definition of the potential for turbine engines to minimize pollution, energy consumption, and noise; (2) to provide a useful means of comparison of the types of engine based on consistent assumptions and a common analytical approach; and (3) to provide a compendium of comparative performance data that would serve as the technical basis for future planning. Emphasis was on establishing comparison trends rather than on absolute values and a definitive engine selection. The primary value of this study is intended to be usefulness of the results to provide a quantitative basis for future judgement.
A technology evaluation study on axially grooved heat pipes is presented. The state-of-the-art is reviewed and present and future requirements are identified. Analytical models, the Groove Analysis Program (GAP) and a closed form solution, were developed to facilitate parametric performance evaluations. GAP provides a numerical solution of the differential equations which govern the hydrodynamic flow. The model accounts for liquid recession, liquid/vapor shear interaction, puddle flow as well as laminar and turbulent vapor flow conditions. The closed form solution was developed to reduce computation time and complexity in parametric evaluations. It is applicable to laminar and ideal charge conditions, liquid/vapor shear interaction, and an empirical liquid flow factor which accounts for groove geometry and liquid recession effects. The validity of the closed form solution is verified by comparison with GAP predictions and measured data.
An initial design study and the development results of an S band RF power transmitting phased array antenna experiment system are presented. The array was to be designed, constructed and instrumented to permit wireless power transmission technology evaluation measurements. The planned measurements were to provide data relative to the achievable performance in the state of the art of flexible surface, retrodirective arrays, as a step in technically evaluating the satellite power system concept for importing to earth, via microwave beams, the nearly continuous solar power available in geosynchronous orbit. Details of the microwave power transmitting phased array design, instrumentation approaches, system block diagrams, and measured component and breadboard characteristics achieved are presented.
The Transonic Aircraft Technology (TACT) research program provided data necessary to verify aerodynamic concepts, such as the supercritical wing, and to gain the confidence required for the application of such technology to advanced high performance aircraft. An F-111A aircraft was employed as the flight test bed to provide full scale data. The data were correlated extensively with predictions based on data obtained from wind tunnel tests. An assessment of the improvement afforded at transonic speeds in drag divergence, maneuvering performance, and airplane handling qualities by the use of the supercritical wing was included in the program. Transonic flight and wind tunnel testing techniques were investigated, and specific research technologies evaluated were also summarized.
The performance requirements of high-energy batteries for terrestrial applications were examined to establish whether or not these systems showed any promise in aerospace applications. The technology assessment is reported and consists of a battery technology evaluation, preliminary engineering studies, and system selection. Major candidate systems are compared and a program schedule is provided.
The synthesis and evaluation of flight control system architectures for future aircraft are discussed in terms of design features and the requirements for fighter aircraft. Advanced fighter configurations may feature canards, flaperons, two-dimensional vectoring nozzles, a mixing compression inlet, and an advanced turbojet engine. Survey and evaluation technology will also progress to include distributed microprocessors, VLSI and VHSIC microcircuitry, optical circuits, analytic redundancy, etc. Bottom-p and top-down architectures have been investigated to fulfill the reliability, maintainability, cost, and performance goals. A centralized architecture has been devised with line-removable units to facilitate maintainability and reduce weight. Descriptions are provided of the performance parameters and applications of optical elements, photoelastic pressure sensors, rare earth sensors, computing elements, and information transfer system.
An annotated bibliography of technical papers, documents, and memorandums produced by or related to the Software Engineering Laboratory is presented. More than 100 publications are summarized. These publications are summarized. These publications cover many areas of software engineering and range from research reports to software documentation. This document has been updated and reorganized substantially since the original version (SEL-82-006, November 1982). All materials are grouped into five general subject areas for easy reference: (1) the software engineering laboratory; (2) software tools; (3) models and measures; (4) technology evaluations; and (5) data collection. An index further classifies these documents by specific topic.
Soil moisture has been identified as a controlling parameter in the occurrence of atmospheric variations and crop vigor. Evapotranspiration rates impact local temperature, precipitation and motion fields of the atmosphere. The multiple beam pushbroom microwave radiometer (MBPMR) is a candidate for moisture monitoring on the Earth Observation System. A prototype MBPMR has been devised for airborne technology evaluations of pushbroom scanning capabilities. The instrument scans at 1.4 GHz with a Diche radiometer. Test flights on a NASA aircraft with the antenna mounted on the bottom of the fuselage have generated soil moisture data over crop areas for which ground truth data were gathered. Large antennas deployed from the Orbiter could collect sufficient data for mapping the global soil moisture in 6 days.
The new national initiative in space reactor technology evaluation and development is strongly tied to mission applications and to spacecraft and space transportation system (STS) compatibility. This paper discusses the power system integration interfaces with potential using spacecraft and the STS, and the impact of these requirements on the design. The integration areas of interest are mechanical, thermal, electrical, attitude control, and mission environments. The mission environments include space vacuum, solar input, heat sink, space radiation, weapons effects, and reactor power system radiation environments. The natural, reactor, and weapons effects radiation must be evaluated and combined to define the design requirements for spacecraft electronic equipment.
The objectives of the Flat-plate Solar Array (FSA) Project Silicon Material Task are to evaluate technologies, new and old; to develop the most promising technologies; to establish practicality of the processes to meet production, energy use, and economic criteria; and to develop an information base on impurities in polysilicon and to determine their effects on solar cell performance. The approach involves determining process feasibility, setting milestones for the forced selection of the processes, and establishing the technical readiness of the integrated process.
The Software Engineering Laboratory (SEL) organization, operation, and research activities are summarized. The results of specific projects in the areas of technology evaluation and software measurement are described.
Topics addressed include: software technology evaluation programs; collection of valid software engineering data; test processes using structural coverage; prototype expert system for software engineering management; use of an environment characteristic software metric set; software modulation; software development by analysis of change; and independent verification and validation.
Development test activities on Mod I engines directed toward evaluating technologies for potential inclusion in the Mod II engine are summarized. Activities covered include: test of a 12-tube combustion gas recirculation combustor; manufacture and flow-distribution test of a two-manifold annular heater head; piston rod/piston base joint; single-solid piston rings; and a digital air/fuel concept. Also summarized are results of a formal assessment of candidate technologies for the Mod II engine, and preliminary design work for the Mod II. The overall program philosophy weight is outlined, and data and test results are presented.