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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 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

Space power by ground-based laser illumination

Reducing energy storage requirements of space power systems by illuminating the photovoltaic arrays with a remotely located laser system is addressed. It is proposed that large lasers be located on cloud-free sites at one or more ground locations and that large lenses or mirrors with adaptive optical correction be used to reduce the beam spread due to diffraction or atmospheric turbulence. During the eclipse periods or lunar night, the lasers illuminate the solar arrays to a level sufficient to provide operating power. Two applications are discussed: illumination of geosynchronous orbit satellites and illumination of a moonbase power system. Issues for photovoltaic receivers for such a system are discussed.

Landis, Geoffrey A.↗
NASA NTRS1992

Periodic magnetopause oscillations observed with the GOES satellites on March 24, 1991

The GOES 6 and 7 satellites were in the dayside magnetosphere late on March 24, 1991, when the magnetopause moved in to geosynchronous orbit. Observations on GOES 6 near 1030 local time (LT) indicated six inward and outward periodic movements of the magnetopause past the satellite over a 30-min interval. Later the magnetopause moved farther in, placing GOES 6 (1100 LT) in the magnetosheath and then moving in past GOES 7, near 1245 LT. The periodic oscillations of the magnetopause at GOES 6 suggest surface waves propagating toward the dawn flank of the magnetopause.

Cahill, L. J., Jr.↗
NASA NTRS1991

Development testing of the advanced photovoltaic solar array

The latest design, fabrication and testing details of a prototype wing are discussed. Estimates of array-level performance are presented as a function of power level and solar cell technology for geosynchronous orbit (GEO) missions and solar electric propulsion missions through the Van Allen radiation belts. Design concepts are discussed that would allow the wing to be self-retractable and restowable. To date all testing has verified the feasibility and mechanical/electrical integrity of the baseline design. The beginning-of-life (BOL) specific power estimate for a nominal 10-kW (BOL) array is about 138 W/kg, with corresponding end-of-life (EOL) performance of about 93 W/kg for a 10-year GEO mission.

Stella, P. M.↗
NASA NTRS1992

Power system requirements

An overview of electrical power requirements for each mission of a baseline and alternate plan for space activities in the 1990-2035 timeframe is presented. The specific missions included low earth orbit (LEO), geosynchronous earth orbit (GEO), lunar, Mars, and asteroid related projects.

Conway, Edmund J.↗
NASA NTRS1992

Beamed energy propulsion

Beamed energy concepts offer an alternative for an advanced propulsion system. The use of a remote power source reduces the weight of the propulsion system in flight and this, combined with the high performance, provides significant payload gains. Within the context of this study's baseline scenario, two beamed energy propulsion concepts are potentially attractive: solar thermal propulsion and laser thermal propulsion. The conceived beamed energy propulsion devices generally provide low thrust (tens of pounds to hundreds of pounds); therefore, they are typically suggested for cargo transportation. For the baseline scenario, these propulsion system can provide propulsion between the following nodes: (1) low Earth orbit to geosynchronous Earth orbit; (2) low Earth orbit to low lunar orbit; (3) low lunar orbit to low Mars orbit--only solar thermal; and (4) lunar surface to low lunar orbit--only laser thermal.

Shoji, James M.↗
NASA NTRS1991

Geostationary earth climate sensor: Scientific utility and feasibility, phase A

The possibility of accurate broad band radiation budget measurements from a GEO platform will provide a unique opportunity for viewing radiation processes in the atmosphere-ocean system. The CSU/TRW team has prepared a Phase 1 instrument design study demonstrating that measurements of radiation budget are practical from geosynchronous orbit with proven technology. This instrument concept is the Geostationary Earth Climate Sensor (GECS). A range of resolutions down to 20 km at the top of the atmosphere are possible, depending upon the scientific goals of the experiment. These tradeoffs of resolution and measurement repeat cycles are examined for scientific utility. The design of a flexible instrument is shown to be possible to meet the two goals: long-term, systematic monitoring of the diurnal cycles of radiation budget; and high time and space resolution studies of regional radiation features.

Campbell, G. Garrett↗
NASA NTRS1992

Extraction of volatiles and metals from extraterrestrial materials

Recent progress in defining the physical, orbital, and chemical properties of the Earth-crossing asteroid and comet population was integrated into an elaborate Monte Carlo model of the fluxes of bodies in the inner Solar System. This model is of use in projecting flight opportunities to as-yet undiscovered near-Earth objects and in assessing the impact hazard to life on Earth and the evolutionary consequences of impacts on the other terrestrial planets. Further progress was made in defining desirable transportation system architectures for the use of non-terrestrial volatiles and metals, including the delivery of propellants to near-Earth space for fueling of space exploration initiative (SEI) type expeditions, the construction and resupply of Solar Power Satellite constellations in various Earth orbits (including geosynchronous earth orbit (GEO) and Highly Eccentric Earth Orbit (HEEO)), and retrieval of He-3 for use as a clean fusion fuel on Earth. These studies suggest a greater future role for SERC in the exploration of space energy sources to meet Earth's 21st-century energy requirements. Laboratory studies of volatilization and deposition of ferrous metal alloys demonstrated deposition of strong iron films from carbonyl chemical vapor deposition (CVD), showing the crucial role of additive gases in governing the CVD process, and pointing the way to specific experiments on extraction and deposition of ferrous metals from nonterrestrial materials.

Lewis, J. S.↗
NASA NTRS1990

The International Ultraviolet Explorer (IUE)

The International Ultraviolet Explorer (IUE) was launched into a geosynchronous orbit on 26 January 1978. It is equipped with a 45-cm mirror and spectrographs operating in the far-ultraviolet (1150-2000 A) and the midultraviolet (1900-3200 A) wavelength regions. In a low-dispersion mode, the spectral resolution is some 6-7 A. In a high-dispersion echelle mode, the resolution is about 0.1 Aat the shortest wavelength and about 0.3 A at the longest. It is a collaborative program among NASA, ESA, and the British SERC. The IUE is operated in real time 16 hours a day from NASA Goddard Space Flight Center near Washington, D.C. and 8 hours daily from ESA's Villafranca groundstation near Madrid, Spain. By the end of 1989, 1870 papers, using IUE observations, have been published in referred journals. During the same period, over 1700 different astronomers from all over the world used the IUE for their research.

Kondo, Yoji↗
NASA NTRS1993

Development of radiometer windows for atmospheric entry vehicles

A test program was established to determine the feasibility of developing a radiometer window for stagnation region shock layer atmospheric entry experiments from geosynchronous orbit and with measurements extending into the VUV region to about 170 nm. This test program examined both isolated (uncooled) and cooled window mounting options. Preliminary tests determined the gross suitability of sapphire and fused silica as window materials. Measurements show that the expected maximum temperature (1500 C) is itself not a problem, but that temperature gradients can easily break a window and that the transmission of sapphire and of fused silica at 174 nm drops dramatically at temperatures beyond 800 C and 500 C, respectively. A series of developmental tests showed that the surface of an uncooled fused silica window begins to melt at the entry conditions tested while an uncooled sapphire window generally does not, and that a cooled sapphire window design that keeps the window below 800 C appears possible. The final proof-of-design tests narrowed the selection of possible candidate window sizes and mounting configurations. These tests demonstrate that the best insulated and cooled window designs use small diameter sapphire windows and that thermal modeling codes can be used to assist the design process.

Terrazas-Salinas, Imelda↗
NASA NTRS1990

Evolutionary Space Station fluids management

The demand for and management issues associated with fluids usage at the evolutionary Space Station are examined. A variety of fluids such as N2, He, methane and rare gases for research and development activities as well as massive quantities of cryogenic propellants for geosynchronous orbit and planetary exploration missions will need to be accommodated at the Space Station. A data base of fluid types, quantities, and projected usage schedules suggested, and potential accommodation concepts defined. Impacts to the Space Station operational configuration and necessary 'hooks and scars' to be included in the baseline design are addressed. Also presented is an operational scenario of the delivery of a cryogenic propellant tank set to the Space Station, attachment to the Space Station, and propellant transfer to and launch of a space transfer vehicle (STV). Results indicate that the cryogenic propellant requirements of STV and lunar missions may be met by tank sets attached to the Space Station, but those of Mars missions would require off-station methods.

Stevenson, Steve↗
NASA NTRS1993

Investigation of passive atmospheric sounding using millimeter and submillimeter wavelength channels

Progress by investigators at the Georgia Institute of Technology in the development of techniques for passive microwave retrieval of water vapor, cloud, and precipitation parameters using millimeter- and sub-millimeter wavelength channels is reviewed. Channels of particular interest are in the tropospheric transmission windows at 90, 166, 220, 340, and 410 GHz and centered around the water vapor lines at 183 and 325 GHz. Collectively, these channels have potential application in high-resolution mapping (e.g., from geosynchronous orbit), remote sensing of cloud and precipitation parameters, and retrieval of water vapor profiles. During the period from 1 Jan. 1993 through 30 Jun. 1993 the Millimeter-wave Imaging Radiometer (MIR) completed data flights during a two-month long deployment in conjunction with TOGA/COARE. Coincident data was collected from several other ground-based, airborne, and satellite sensors, including the NASA/MSFC AMPR, MIT MTS, DMSP SSM/T-2 satellite, collocated radiosondes, ground- and aircraft-based radiometers and cloud lidars, airborne infrared imagers, solar flux probes, and airborne cloud particle sampling probes.

Gasiewski, A. J.↗
NASA NTRS1993

TROPIX: A solar electric propulsion flight experiment

The Transfer Orbit Plasma Interaction Experiment (TROPIX) is a proposed scientific experiment and flight demonstration of a solar electric propulsion vehicle. Its mission goals are to significantly increase our knowledge of Earth's magnetosphere and its associated plasma environment and to demonstrate an operational solar electric upper stage (SEUS) for small launch vehicles. The scientific investigations and flight demonstration technology experiments are uniquely interrelated because of the spacecraft's interaction with the surrounding environment. The data obtained will complement previous studies of the Earth's magnetosphere and space plasma environment by supplying the knowledge necessary to attain the strategic objectives of the NASA Office of Space Science. This first operational use of a primary ion propulsion vehicle, designed to withstand the harsh environments from low Earth orbit to geosynchronous Earth orbit, may lead to the development of a new class of electric propulsion upper stages or space-based transfer vehicles and may improve future spacecraft design and safety.

Hickman, J. Mark↗
NASA NTRS1993

NASA Handbook for Nickel-Hydrogen Batteries

Nickel-hydrogen (NiH2) batteries are finding more applications in the aerospace energy storage. Since 1983, NiH2 batteries have become the primary energy storage system used for Geosynchronous-Orbit (GEO) Satellites. The first NASA application for NiH2 batteries was the Low Earth Orbit (LEO) Hubble Space Telescope Satellite launched in 1990. The handbook was prepared as a reference book to aid in the application of this technology. That is, to aid in the cell and battery design, procurement, testing, and handling of NiH2 batteries. The design of individual pressure vessel NiH2 cells is covered in Chapter l. LEO and GEO applications and their requirements are discussed in Chapter 2. The design of NiH2 batteries for both GEO and LEO applications is discussed in Chapter 3. Advanced design concepts such as the common pressure vessel and bipolar NiH2 batteries are described in Chapter 4. Performance data are presented in Chapter 5. Storage and handling of the NiH2 cells and batteries are discussed in Chapter 6. Standard test procedures are presented in Chapter 7. Cell and battery procurements are discussed in Chapter 8. Finally, safety procedures are discussed in Chapter 9.

Dunlop, James D.↗
NASA NTRS1991

Technology, design, simulation, and evaluation for SEP-hardened circuits

This paper describes the technology, design, simulation, and evaluation for improvement of the Single Event Phenomena (SEP) hardness of gate-array and SRAM cells. Through the use of design and processing techniques, it is possible to achieve an SEP error rate less than 1.0 x 10(exp -10) errors/bit-day for a 9O percent worst-case geosynchronous orbit environment.

Adams, J. R.↗
NASA NTRS1993

Proton irradiation on materials

A computer code is developed by utilizing a radiation transport code developed at NASA Langley Research Center to study the proton radiation effects on materials which have potential application in NASA's future space missions. The code covers the proton energy from 0.01 Mev to 100 Gev and is sufficient for energetic protons encountered in both low earth and geosynchronous orbits. With some modification, the code can be extended for particles heavier than proton as the radiation source. The code is capable of calculating the range, stopping power, exit energy, energy deposition coefficients, dose, and cumulative dose along the path of the proton in a target material. The target material can be any combination of the elements with atomic number ranging from 1 to 92, or any compound with known chemical composition. The generated cross section for a material is stored and is reused in future to save computer time. This information can be utilized to calculate the proton dose a material would receive in an orbit when the radiation environment is known. It can also be used to determine, in the laboratory, the parameters such as beam current of proton and irradiation time to attain the desired dosage for accelerated ground testing of any material. It is hoped that the present work be extended to include polymeric and composite materials which are prime candidates for use as coating, electronic components, and structure building. It is also desirable to determine, for ground testing these materials, the laboratory parameters in order to simulate the dose they would receive in space environments. A sample print-out for water subject to 1.5 Mev proton is included as a reference.

Chang, C. Ken↗
NASA NTRS1994

Investigation of passive atmospheric sounding using millimeter and submillimeter wavelength channels

Progress by the Georgia Institute of Technology's Laboratory for Radio-science and Remote Sensing in developing techniques for passive microwave retrieval of water vapor profiles and cloud and precipitation parameters using millimeter and submillimeter wavelength channels is reviewed. Channels of particular interest are in the tropospheric transmission windows at 90, 166, 220, 340, and 410 GHz and centered around the water vapor lines at 183 and 325 GHz. Collectively, these channels have potential application in high-resolution precipitation mapping (e.g., from geosynchronous orbit), remote sensing of cloud and precipitation parameters, including cirrus ice mass, and improved retrieval of water vapor profiles. During the period from January 1, 1994 through June 30, 1994 research activities focussed on calibrating and interpreting data from the Millimeter-Wave Imaging Radiometer (MIR). The MIR was deployed on the NASA ER-2 during the Convective Atmospheric Moisture Experiment (CAMEX, September-October 1993) to obtain the first submillimeter-wave tropospheric imagery of convective precipitations. A 325-GHz radiometer consisted of a submillimeter-wave DSB receiver with three IF channels at +/- 1, 3, and 8.5 GHz, and approximately 14 dB DSB noise figure was successfully operated during these experiments. Activities supported under this grant include a study of the impact of local oscillator reflections from the MIR calibration loads, the development of optimal gain and offset filters for radiometric calibration, and the modeling and interpretation of the MIR 325-GHz data over both clear and cloudy atmospheres. In addition, polarimetric radiometer measurements and modeling for ocean surface and atmospheric cloud-ice studies_were supported.

Gasiewski, Albin J.↗
NASA NTRS1994

Nickel hydrogen batteries: An overview

This paper on nickel hydrogen batteries is an overview of the various nickel hydrogen battery design options, technical accomplishments, validation test results and trends. There is more than one nickel hydrogen battery design, each having its advantage for specific applications. The major battery designs are individual pressure vessel (IPV), common pressure vessel (CPV), bipolar and low pressure metal hydride. State-of-the-art (SOA) nickel hydrogen batteries are replacing nickel cadmium batteries in almost all geosynchronous orbit (GEO) applications requiring power above 1 kW. However, for the more severe low earth orbit (LEO) applications (greater than 30,000 cycles), the current cycle life of 4000 to 10,000 cycles at 60 percent DOD should be improved. A LeRC innovative advanced design IPV nickel hydrogen cell led to a breakthrough in cycle life enabling LEO applications at deep depths of discharge (DOD). A trend for some future satellites is to increase the power level to greater than 6 kW. Another trend is to decrease the power to less than 1 kW for small low cost satellites. Hence, the challenge is to reduce battery mass,volume, and cost. A key is to develop a light weight nickel electrode and alternate battery designs. A common pressure vessel (CPV) nickel hydrogen battery is emerging as a viable alternative to the IPV design. It has the advantage of reduced mass, volume and manufacturing costs. A 10 Ah CPV battery has successfully provided power on the relatively short lived Clementine Spacecraft. A bipolar nickel hydrogen battery design has been demonstrated (15,000 LEO cycles, 40 percent DOD). The advantage is also a significant reduction in volume, a modest reduction in mass, and like most bipolar designs, features a high pulse power capability. A low pressure aerospace nickel metal hydride battery cell has been developed and is on the market. It is a prismatic design which has the advantage of a significant reduction in volume and a reduction in manufacturing cost.

Smithrick, John J.↗
NASA NTRS1995

A review of nickel hydrogen battery technology

This paper on nickel hydrogen batteries is an overview of the various nickel hydrogen battery design options, technical accomplishments, validation test results and trends. There is more than one nickel hydrogen battery design, each having its advantage for specific applications. The major battery designs are individual pressure vessel (IPV), common pressure vessel (CPV), bipolar and low pressure metal hydride. State-of-the-art (SOA) nickel hydrogen batteries are replacing nickel cadmium batteries in almost all geosynchronous orbit (GEO) applications requiring power above 1 kW. However, for the more severe low earth orbit (LEO) applications (greater than 30,000 cycles), the current cycle life of 4000 to 10,000 cycles at 60 percent DOD should be improved. A NASA Lewis Research Center innovative advanced design IPV nickel hydrogen cell led to a breakthrough in cycle life enabling LEO applications at deep depths of discharge (DOD). A trend for some future satellites is to increase the power level to greater than 6 kW. Another trend is to decrease the power to less than 1 kW for small low cost satellites. Hence, the challenge is to reduce battery mass, volume and cost. A key is to develop a light weight nickel electrode and alternate battery designs. A common pressure vessel (CPV) nickel hydrogen battery is emerging as a viable alternative to the IPV design. It has the advantage of reduced mass, volume and manufacturing costs. A 10 Ah CPV battery has successfully provided power on the relatively short lived Clementine Spacecraft. A bipolar nickel hydrogen battery design has been demonstrated (15,000 LEO cycles, 40 percent DOD). The advantage is also a significant reduction in volume, a modest reduction in mass, and like most bipolar designs, features a high pulse power capability. A low pressure aerospace nickel metal hydride battery cell has been developed and is on the market. It is a prismatic design which has the advantage of a significant reduction in volume and a reduction in manufacturing cost.

Smithrick, John J.↗