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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

Space-based solar power conversion and delivery systems (study), engineering analysis

A systems analysis of synchronous, orbit-based power generation and relay systems that could be operational in the 1990's is described along with a comparison with earth-based systems to be operational in the same time frame. Operational and economic requirements for the orbiting systems and near term research activities which will be required to assure feasibility, development, launch and operational capabilities of such systems in the post- 1990 time frame are examined.

Nathan, C. A.↗

Shuttle ECLSS ammonia delivery capability

The possible effects of excessive requirements on ammonia flow rates required for entry cooling, due to extreme temperatures, on mission plans for the space shuttles, were investigated. An analysis of worst case conditions was performed, and indicates that adequate flow rates are available. No mission impact is therefore anticipated.

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Design, fabrication, testing, and delivery of a solar energy collector system for residential heating and cooling

A low cost flat plate solar energy collector was designed for the heating and cooling of residential buildings. The system meets specified performance requirements, at the desired system operating levels, for a useful life of 15 to 20 years, at minimum cost and uses state-of-the-art materials and technology. The rationale for the design method was based on identifying possible material candidates for various collector components and then selecting the components which best meet the solar collector design requirements. The criteria used to eliminate certain materials were: performance and durability test results, cost analysis, and prior solar collector fabrication experience.

Holland, T. H.↗

Space-based solar power conversion and delivery systems study. Volume 1: Executive summary

The technical and economic aspects of satellite solar power systems are presented with a focus on the current configuration 5000 MW system. The technical studies include analyses of the orbital system structures, control and stationkeeping, and the formulation of program plans and costs for input to the economic analyses. The economic analyses centered about the development and use of a risk analysis model for a system cost assessment, identification of critical issues and technologies, and to provide information for programmatic decision making. A preliminary economic examination of some utility interface issues is included. Under the present state-of-knowledge, it is possible to formulate a program plan for the development of a satellite solar power system that can be economically justified. The key area of technological uncertainty is man's ability to fabricate and assemble large structures in space.

Hazelrigg, G. A., Jr.↗

Space-based solar power conversion and delivery systems study. Volume 2: Engineering analysis of orbital systems

Program plans, schedules, and costs are determined for a synchronous orbit-based power generation and relay system. Requirements for the satellite solar power station (SSPS) and the power relay satellite (PRS) are explored. Engineering analysis of large solar arrays, flight mechanics and control, transportation, assembly and maintenance, and microwave transmission are included.

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Space-based solar power conversion and delivery systems study. Volume 3: Economic analysis of space-based solar power systems

A variety of economic and programmatic issues are discussed concerning the development and deployment of a fleet of space-based solar power satellites (SSPS). The costs, uncertainties and risks associated with the current photovoltaic SSPS configuration, and with issues affecting the development of an economically viable SSPS development program are analyzed. The desirability of a low earth orbit (LEO) demonstration satellite and a geosynchronous (GEO) pilot satellite is examined and critical technology areas are identified. In addition, a preliminary examination of utility interface issues is reported. The main focus of the effort reported is the development of SSPS unit production, and operation and maintenance cost models suitable for incorporation into a risk assessment (Monte Carlo) model (RAM). It is shown that the key technology area deals with the productivity of man in space, not, as might be expected, with some hardware component technology.

Hazelrigg, G. A., Jr.↗

Prospects for pipeline delivery of hydrogen as a fuel and as a chemical feedstock

The possibility of using hydrogen for storing and carrying energy obtained from nonfossil sources such as nuclear and solar energy is examined. According to the method proposed, these nonfossil raw energy sources will be used to obtain hydrogen from water by three basically distinct routes: (1) electrical generation followed by electrolysis; (2) thermochemical decomposition; and (3) direct neutron or ultraviolet irradiation of hydrogen bearing molecules. The hydrogen obtained will be transmitted in long-distance pipelines, and distributed to all energy-consuming sectors. As a fuel gas, hydrogen has many qualities similar to natural gas and with only minor modifications, it can be transmitted and distributed in the same equipment, and can be burned in the same appliances as natural gas. Hydrogen can also be used as a clean fuel (water is the only combustion product) for automobiles, fleet vehicles, and aircraft.

Gregory, D. P.↗

Remote-area health care delivery through space technology - STARPAHC

A joint NASA/HEW project called Space Technology Applied to Rural Papage Advanced Health Care (STARPAHC) has been developed to deliver quality health care to inhabitants of remote geographical areas. The system consists of a hospital-based support control center, a fixed clinic, a mobile clinic, and a referral center with access to specialists via television links to the control center. A strategically located relay station routes television, voice, and data transmissions between system elements. A model system has been installed on the Papage Indian Reservation in Arizona, and is undergoing a 2-year evaluation. The system has been shown to be both effective and cost-efficient, and applications of the concept are planned for future manned spacecraft flights.

Belasco, N.↗

Baseline tests of the power-train electric delivery van

Vehicle maximum speed, range at constant speed, range over stop-and-go driving schedules, maximum acceleration, gradeability, gradeability limit, road energy consumption, road power, indicated energy consumption, braking capability, battery charger efficiency, and battery characteristics were determined for a modified utility van powered by sixteen 6-volt batteries connected in series. A chopper controller actuated by a foot accelerator pedal changes the voltage applied to the 22-kilowatt (30-hp) series-wound drive motor. In addition to the conventional hydraulic braking system, the vehicle has hydraulic regenerative braking. Cycle tests and acceleration tests were conducted with and without hydraulic regeneration.

Lumannick, S.↗

Baseline tests of the battronic Minivan electric delivery van

An electric passenger vehicle was tested to develop data characterizing the state of the art of electric and hybrid vehicles. The test measured vehicle maximum speed, range at constant speed, range over stop-and-go driving schedules, maximum acceleration, gradeability and limit, road energy consumption, road power, indicated energy consumption, braking capability and battery charge efficiency. The data obtained are to serve as a baseline to compare improvements in electric and hybrid vehicle technologies and to assist in establishing performance standards.

Dustin, M. O.↗

Design, fabrication and delivery of a prototype saturator for ACPL

The design configuration and performance characteristics of a saturator developed to provide ground-based simulation for some of the experiments for ACPL-1 first flights of Spacelab are described, some difficulties encountered with the apparatus are discussed, and recommendations concerning testing of this type of instrument are presented. The saturators provide a means of accurately fixing the water vapor mixing ratio of an aerosol sample. Dew point temperatures from almost freezing to ambient room temperatures can be attained with high precision. The instruments can accommodate aerosol flow rates approaching 1000 cc/s. Provisions were made to inject aerosols upstream of these saturators, although downstream injection can be accomplished as well. A device of this type will be used in the ACPL-1 to condition various aerosols delivered concurrently to a CFD, expansion chamber, and static diffusion chamber used in zero gravity cloud-forming experiments. The saturator was designed to meet the requirements projected for the flight instrument.

Keyser, G.↗

Space-based solar power conversion and delivery systems study. Volume 2: Engineering analysis

The technical and economic feasibility of Satellite Solar Power Systems was studied with emphasis on the analysis and definition of an integrated strawman configuration concept, from which credible cost data could be estimated. Specifically, system concepts for each of the major subprogram areas were formulated, analyzed, and iterated to the degree necessary for establishing an overall, workable baseline system design. Cost data were estimated for the baseline and used to conduct economic analyses. The baseline concept selected was a 5-GW crystal silicon truss-type photovoltaic configuration, which represented the most mature concept available. The overall results and major findings, and the results of technical analyses performed during the final phase of the study efforts are reported.

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Space-Based Solar Power Conversion and Delivery Systems Study. Volume 3: Microwave Power Transmission Studies

The Microwave Fower Beam Ionosphere effects and critical interfaces between th Microwave Power Transmission System (MPTS) and the Satellite were studied as part of the NASA/MSFC continuing research on the feasibility of power transmission from geosynchronous orbit. Theoretical predications of ionospheric modifications produced by the direct interaction of the MPTS on the earth's upper atmosphere are used to determine their impact on the performance of the Microwave Power Beam and Pilot Beam System as well as on other RF systems effected by the ionosphere. A technology program to quantitatively define these interactions is developed. Critical interface areas between the MPTS and the satellite which could have a major impact on cost and performance of the power system are idenfified and analyzed. The areas selected include: use of either a 20 kV versus 40 kV Amplitron, thermal blockage effects of Amplitron heat radiation by the satellite structure, effect of dielectric carry-through structure on power beam, and effect of material sublimation on performance of the Amplitron in Geosynchronous Orbit.

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Space-based solar power conversion and delivery systems study. Volume 4: Energy conversion systems studies

Solar cells and optical configurations for the SSPS were examined. In this task, three specific solar cell materials were examined: single crystal silicon, single crystal gallium arsenide, and polycrystalline cadmium sulfide. The comparison of the three different cells on the basis of a subsystem parametric cost per kW of SSPS-generated power at the terrestrial utility interface showed that gallium arsenide was the most promising solar cell material at high concentration ratios. The most promising solar cell material with no concentration, was dependent upon the particular combination of parameters representing cost, mass and performance that were chosen to represent each cell in this deterministic comparative analysis. The potential for mass production, based on the projections of the present state-of-the-art would tend to favor cadmium sulfide in lieu of single crystal silicon or gallium arsenide solar cells.

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Design, fabrication, and delivery of a charge injection device as a stellar tracking device

Six 128 x 128 CID imagers fabricated on bulk silicon and with thin polysilicon upper-level electrodes were tested in a star tracking mode. Noise and spectral response were measured as a function of temperature over the range of +25 C to -40 C. Noise at 0 C and below was less than 40 rms carriers/pixel for all devices at an effective noise bandwidth of 150 Hz. Quantum yield for all devices averaged 40% from 0.4 to 1.0 microns with no measurable temperature dependence. Extrapolating from these performance parameters to those of a large (400 x 400) array and accounting for design and processing improvements, indicates that the larger array would show a further improvement in noise performance -- on the order of 25 carriers. A preliminary evaluation of the projected performance of the 400 x 400 array and a representative set of star sensor requirements indicates that the CID has excellent potential as a stellar tracking device.

Burke, H. K.↗

Design, fabrication and delivery of a high pressure LOX-methane injector

An injector for 3000 psia chamber pressure using liquid oxygen and gaseous methane propellants is presented. The injector is intended to be evaluated during a series of pressure-fed test firings using a water-cooled calorimeter chamber and a milled-slot regenerative chamber. Combustion efficiency, combustion stability, ignition and injector face heat transfer assessments were made for candidate injector body and pattern design approaches. This evaluation resulted in baselining an oxidizer post type manifold with a 60 element platelet coaxial swirler injector pattern. An axial acoustic resonator cavity was created at the injector/chamber interface.

Valler, H. W.↗

Pioneer Venus Unified Abstract Data Library and Quick Look Data Delivery System

Development of the Pioneer Venus (PV) Unified Abstract Data System (UADS) and Quick Look Data System (QLDS) was prompted by the need to provide PV investigators rapid and easy access to PV mission data. The UADS is intended to maximize the scientific benefits of the mission by facilitating the exchange of reduced scientific data. QLDS provides a method by which sampled daily mission data is rapidly transmitted to principal investigators providing them a quick look at that orbit's data.

Ferandin, J. A.↗