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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 1,279 records · Page 71
All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

Power Extension Package (PEP) system definition extension, orbital service module systems analysis study. Volume 1: Executive summary

An array deployment assembly, power regulation and control assembly, the necessary interface, and display and control equipment comprise the power extension package (PEP) which is designed to provide increased power and duration, as well as reduce fuel cell cryogen consumption during Spacelab missions. Compatible with all currently defined missions and payloads, PEP imposes minimal weight and volume penalties on sortie missions, and can be installed and removed as needed at the launch site within the normal Orbiter turnaround cycle. The technology on which it is based consists of a modified solar electric propulsion array, standard design regulator and control equipment, and a minimally modified Orbiter design. The requirements from which PEP was derived, and the system and its performance capabilities are described. Features of the recommended project are presented.

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NASA NTRS1978

Extended duration Orbiter life support definition

Extending the baseline seven-day Orbiter mission to 30 days or longer and operating with a solar power module as the primary source for electrical power requires changes to the existing environmental control and life support (ECLS) system. The existing ECLS system imposes penalties on longer missions which limit the Orbiter capabilities and changes are required to enhance overall mission objectives. Some of these penalties are: large quantities of expendables, the need to dump or store large quantities of waste material, the need to schedule fuel cell operation, and a high landing weight penalty. This paper presents the study ground rules and examines the limitations of the present ECLS system against Extended Duration Orbiter mission requirements. Alternate methods of accomplishing ECLS functions for the Extended Duration Orbiter are discussed. The overall impact of integrating these options into the Orbiter are evaluated and significant Orbiter weight and volume savings with the recommended approaches are described.

Kleiner, G. N.↗
NASA NTRS1979

Energy storage for low earth orbit operations at high power

Results are presented of an in-house study of relative sizes and technology needs of three energy storage systems for high power, low earth orbit power systems. The systems compared are nickel-cadmium batteries, nickel-hydrogen batteries, and regenerative fuel cell systems (RFCS). RFCS based on hydrogen-oxygen and hydrogen-chlorine reactants are examined. Those components of the total power system which are significantly impacted by energy storage system selection; e.g., solar array, reactant storage tanks and radiator sizes, are included incrementally in the weights of the systems compared.

Trout, J. B.↗
NASA NTRS1979

Demand and supply of hydrogen as chemical feedstock in USA

Projections are made for the demand and supply of hydrogen as chemical feedstock in USA. Industrial sectors considered are petroleum refining, ammonia synthesis, methanol production, isocyanate manufacture, edible oil processing, coal liquefaction, fuel cell electricity generation, and direct iron reduction. Presently, almost all the hydrogen required is produced by reforming of natural gas or petroleum fractions. Specific needs and emphases are recommended for future research and development to produce hydrogen from other sources to meet the requirements of these industrial sectors. The data and the recommendations summarized in this paper are based on the Workshop 'Supply and Demand of Hydrogen as Chemical Feedstock' held at the University of Houston on December 12-14, 1977.

Huang, C. J.↗
NASA NTRS1979

25-kW power module

The 25-kW power module design and operational characteristics and the benefits for payloads are presented. The module will allow the Shuttle Orbiter to be utilized on-orbit to its optimum capability of power and duration for sortie/Spacelab missions, and will provide central power-rich base for free-flyer payloads requiring increased electrical power and on-orbit stay-times of up to 5 years. Concepts of the module in the sortie and free-flyer modes are depicted with resource capabilities for experimentation in astronomy, solar physics, solar terrestrial observations, and materials processing which require long duration and/or high power missions. In the sortie mode operation the Orbiter fuel cell will be in an idle mode, with the 25-kW module providing payload power needs, and in the free-flyer mode the module will provide power needs to multiple payloads. Design considerations, the thermal control subsystem, the attitude control subsystem, command and data handling, and the electrical power subsystem are described.

Powell, L. E.↗
NASA NTRS1980

Simple buck/boost voltage regulator

Circuit corrects low or high supply voltage, produces regulated output voltage. Circuit has fewer components because inductory/transformer combination and pulse-width modulator serve double duty. Regulator handles input voltage variation from as low as one half output voltage to as high as input transistor rating. Solar arrays, fuel cells, and thermionic generators might use this regulator.

Paulkovich, J.↗
NASA NTRS1979

Test evaluation of shock buffering concept for hydrodynamic ram induced by yawing projectile impacting a simulated integral fuel tank

A concept for containing the shock inputs due to hydrodynamic ram caused by an impacting projectile within a fuel cell is discussed. This is to provide a buffering layer of foam, flexible, rigid or a combination thereof, which is sealed from the liquid. A program is described in which this buffering concept was tested. The effectiveness of a novel muzzle-mounted, 'tumble', test device is shown.

Zabel, P. H.↗
NASA NTRS1979

Hydrazine monopropellant reciprocating engine development

A hydrazine-fueled piston-type engine for providing 11.2 kW (15 hp) has been developed to satisfy the need for an efficient power supply in the range from 3.7 to 74.6 kW (5 to 100 hp) where existing nonair-breathing power supplies such as fuel cells or turbines are inappropriate. The engine was developed for an aircraft to fly to 21.3 km (70,000 ft) and above and cruise for extended periods. The NASA Hugh L. Dryden Flight Research Center developed a remotely piloted aircraft and the associated flight control techniques for this application. About 20 hr of run time have demonstrated good efficiency and adequate life. One flight test to 6.1 km (20,000 ft) has been made using the engine with a small fixed-pitch four-bladed propeller. The test was successful in demonstrating operational characteristics and future potential.

Akkerman, J. W.↗
NASA NTRS1982

Power-MOSFET Voltage Regulator

Ninety-six parallel MOSFET devices with two-stage feedback circuit form a high-current dc voltage regulator that also acts as fully-on solid-state switch when fuel-cell out-put falls below regulated voltage. Ripple voltage is less than 20 mV, transient recovery time is less than 50 ms. Parallel MOSFET's act as high-current dc regulator and switch. Regulator can be used wherever large direct currents must be controlled. Can be applied to inverters, industrial furnaces photovoltaic solar generators, dc motors, and electric autos.

Miller, W. N.↗
NASA NTRS1980

Orbiter integrated active thermal control subsystem test

Integrated subsystem level testing of the systems within the orbiter active thermal chamber capable of simulating ground, orbital, and entry temperature and pressure profiles. The test article was in a closed loop configuration that included flight type and functionally simulated protions of all ATCS components for collecting, transporting, and rejecting orbiter waste heat. Specially designed independently operating equipment simulated the transient thermal input from the cabin, payload, fuel cells, freon cold plates, hydraulic system, and space environment. Test team members using data, controls, and procedures available to a flight crew controlled the operation of the ATCS. The ATCS performance met or exceeded all thermal and operational requirements for planned and contingency mission support.

Jaax, J. R.↗
NASA NTRS1981

Evaluation of distributed gas cooling of pressurized PAFC for utility power generation

Two short stacks were pressure tested at 446 kPa (4.4 atm.) and the pressure gains were more than the theoretically predicted gains. Temperature profiles were observed to be independent of operating pressure. The pressure drop was found to be inversely proportional to operating pressure as expected. Continuous pressurized operation of a stack for 1000 hours verified the compatability of the fuel cell component design. A simple pressurization procedure was also developed. Six separate designs, covering two gas cooling schemes (DIGAS and separated) and two cooling channel geometries (straight through and treed), were analysed on the net voltage output basis. Separated cooling with 5 cells per cooler was recognized to be the best among the designs considered.

Farooque, M.↗
NASA NTRS1980

Control of volume resistivity in inorganic-organic separators

Control of resistivity in NASA inorganic-organic separators is achieved by incorporating small percentages of high surface area, fine-particle silica with other ingredients in the separator coating. The volume resistivity appears to be predictable from coating composition, that is, from the surface area of filler particles in the coating. The approach has been applied to two polymer-'plasticizer'-filler coating systems, where the filler content of each is below the generally acknowledged critical pigment volume concentration of the coating. Application of these coating systems to 0.0254 cm thick (10 mil) fuel-cell grade asbestos sheet produces inexpensive, flexible, microporous separators that perform at least as well as the original inorganic-organic concept, the Astropower separator.

Sheibley, D. W.↗
NASA NTRS1981

Low thrust chemical propulsion for orbit transfer of large space structures

For transporting Large Space Structures (LSS) from Low Earth Orbit (LEO) to Geosynchronous Equatorial Orbit (GEO), a variety of low thrust engine cycles have been evaluated for oxygen/hydrogen and oxygen/hydrocarbon propellants. The engine cycles included conventional propellant turbine drives (gas generator, expander, and staged-combustion cycles), turboalternator/electric motor pump drive, and fuel-cell/electric motor pump drive, as well as pressure-fed engines. The thrust chamber cooling limits and the engine cycle limits were established for a range of thrust levels. The candidate engine cycles were analyzed, screened, rated, and two engine cycle/configurations were selected for preliminary engine design. Preliminary engine designs for these two engines were formulated and engine design layouts prepared and parametric engine data generated.

Shoji, J. M.↗
NASA NTRS1981

Study of multi-megawatt technology needs for photovoltaic space power systems. Volume 1: Executive summary

Possible missions requiring multimegawatt photovoltaic space power systems in the 1990's time frame and associated power system technology needs are examined. The following concepts for photovoltaic power approaches are considered: planar arrays, concentrating arrays, hybrid systems using Rankine engines, thermophotovoltaic and AC/DC power management approaches, battery, fuel cell, flywheel energy storage, and interactions with the electrical ion engine injection and stationkeeping system. The levels of modularity for efficient, safe, constructable, serviceable, and cost effective system design are analyzed, and the benefits of alternate approaches developed. Both manned low Earth orbit and unmanned geosynchronous Earth orbit applications were examined for technological development. Technology developments applicable to power systems which appear to have benefits independent of the absolute power level are suggested.

Peterson, D. M.↗
NASA NTRS1981

The 1981 NASA ASEE Summer Faculty Fellowship Program, volume 1

A review of NASA research programs related to developing and improving space flight technology is presented. Technical report topics summarized include: space flight feeding; aerospace medicine; reusable spacecraft; satellite soil, vegetation, and climate studies; microwave landing systems; anthropometric studies; satellite antennas; and space shuttle fuel cells.

Robertson, N. G.↗
NASA NTRS1982

STS-2 medical report

All medially related activities of the Space Transportation System 2 flight are described, ranging from preflight to postflight. Several medical problems occured during the flight. Their was marginal operation on-board potable water system caused by a malfunctioning fuel cell. Work and rest cycles by the crew were altered to maximize the scientific data acquisition. Inadequate time was allocated for food preparation and consumption. There was low water intake by the crew because of the water shortage.

Pool, S. L.↗
NASA NTRS1982

Laser processing

Progress in the Progress ceramic materials is reported. Experiments and models for sintering and microstructure evolution are described. Models and data for understanding the kinetics of grain boundary motion and of pore coarsening and new materials for fuel cells and batteries; are developed. New experimental techniques using lasers for forming fine, monosized powders and for forming stable and metastable structures from liquids, and solar materials research are also developed. Colloidal science and ceramics processing are explored; and research programs on the presintering science necessary for controlled green microstructures are outlined.

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