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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 127 records · Page 7

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NASA NTRS1971

Space shuttle low pressure auxiliary propulsion subsystem design definition: Design handbook

A detailed description of recommended low pressure auxiliary propulsion subsystems (APS) for a space shuttle orbiter and booster is presented. The APS designs are the product of a study to identify and evaluate APS concepts, and to perform in-depth design and performance analyses for the most attractive of these. Selected APS baselines use the main engine propellant tanks as low pressure gas accumulators. For the orbiter, propellants from separate liquid tanks are used for main engine tank resupply. Resupply propellants are first circulated through tubular, passive heat exchangers, where they are vaporized and superheated prior to injection into the main engine tanks. Warm propellant vapors from the main engine tanks are mixed with additional liquid propellants in a downstream liquid/vapor mixer and supplied to the engines at constant temperature and pressure (constant density). The booster APS requires no separate propellant storage, since propellant residuals, trapped in the main engine tanks following boost, are sufficient to meet APS propellant demands.

Bruns, A. E.↗

NASA NTRS1973

Space shuttle aps propellant thermal conditioner study

An analytical and experimental effort was completed to evaluate a baffle type thermal conditioner for superheating O2 and H2 at supercritical pressures. The thermal conditioner consisted of a heat exchanger and an integral reactor (gas generator) operating on O2/H2 propellants. Primary emphasis was placed on the hydrogen conditioner with some effort on the oxygen conditioner and a study completed of alternate concepts for use in conditioning oxygen. A hydrogen conditioner was hot fire tested under a range of conditions to establish ignition, heat exchange and response parameters. A parallel technology task was completed to further evaluate the integral reactor and heat exchanger with the side mounted electrical spark igniter.

Fulton, D. L.↗

NASA NTRS1974

Flow studies in a wet steam turbine

The design and test results of a four stage wet vapor turbine operating with slightly superheated inlet steam and expanding to 10% exit moisture are presented. High speed movies at 3000 frames per second of liquid movement on the pressure side and along the trailing edge of the last stator blade are discussed along with back lighted photographs of moisture drops as they were torn from the stator blade trailing edge. Movies at lower framing rates were also taken of the exit of the last rotating blade and the casing moisture removal slot located in line with the rotor blade shroud. Also moisture removal data are presented of casing slot removal at the exit of the third and fourth rotor blades and for slots located in the trailing edge of the last stator blade. Finally, the degradation of turbine thermodynamic performance due to condensation formation and movement is discussed.

Evans, D. H.↗

NASA NTRS1973

Free suspension processing of oxides to form amorphous oxide materials, appendix B

The processing of yttria, zirconia, and alumina under weightless conditions is discussed. The process consists of levitation or position control, heating and melting, superheating, and supercooling. The use of arc imaging furnaces, lasers, induction heating, microwave, and electron beam methods are analyzed to show the advantages and disadvantages of each.

Wouch, G.↗

NASA NTRS1974

Dynamic conversion of solar generated heat to electricity

The effort undertaken during this program led to the selection of the water-superheated steam (850 psig/900 F) crescent central receiver as the preferred concept from among 11 candidate systems across the technological spectrum of the dynamic conversion of solar generated heat to electricity. The solar power plant designs were investigated in the range of plant capacities from 100 to 1000 Mw(e). The investigations considered the impacts of plant size, collector design, feed-water temperature ratio, heat rejection equipment, ground cover, and location on solar power technical and economic feasibility. For the distributed receiver systems, the optimization studies showed that plant capacities less than 100 Mw(e) may be best. Although the size of central receiver concepts was not parametrically investigated, all indications are that the optimal plant capacity for central receiver systems will be in the range from 50 to 200 Mw(e). Solar thermal power plant site selection criteria and methodology were also established and used to evaluate potentially suitable sites. The result of this effort was to identify a site south of Inyokern, California, as typically suitable for a solar thermal power plant. The criteria used in the selection process included insolation and climatological characteristics, topography, and seismic history as well as water availability.

Powell, J. C.↗

NASA NTRS1975

T-111 Rankine system corrosion test loop, volume 1

Results are given of a program whose objective was to determine the performance of refractory metal alloys in a two loop Rankine test system. The test system consisted of a circulating lithium circuit heated to 1230 C maximum transferring heat to a boiling potassium circuit with a 1170 C superheated vapor temperature. The results demonstrate the suitability of the selected refractory alloys to perform from a chemical compatibility standpoint.

Harrison, R. W.↗

NASA NTRS1976

Flight 1 technical report for experiment 74-37 contained polycrystalline solidification in low-G

A .005 M solution of fluorescein in cyclohexanol was directionally solidified in a standard 10 x 10 x 45mm UV silica cuvette, using a bottom thermoelectric chilling device. Progress of the experiment was monitored by time lapse photography. During flight (SPAR I) the camera malfunctioned and only one quarter of the expected data were collected. Comparison of flight and ground specimens indicated that: (1) The dark green layer observed ahead of the solid-liquid interface which is most likely the solute-enriched zone, appears to be wider in the flight specimen; (2) Parasitic nucleation ahead of the solid-liquid interface in the flight sample led to an irregularly shaped interface, smaller grain size, equiaxed grain morphology and a larger average macroscopic growth rate; (3) The formation of equiaxed grains ahead of the solid-liquid interface in the flight specimen may be attributed to ordered islands within the liquid, which survived remelting because of the low degree of superheating (approximately equal to 1.5 C), did not settle because of reduced gravity and acted as nuclei during cooling.

Papaziak, J. M.↗

NASA NTRS1975

Transition radiation effects in superconducting granules

The paper examines the use of a superheated superconducting suspension as a transition radiation detector of relativistic charged particles. The suspensions would also be used for detecting low-energy X-ray photons. The DESY experiment for developing such a superconducting detector has been carried out at a 7 GeV electron synchrotron. The detection is shown to be based on the recordable flipping of the state of a single superconducting grain.

Drukier, A. K.↗

NASA NTRS1976

Comparative performance of solar thermal power generation concepts

A performance comparison is made between the central receiver system (power tower) and a distributed system using either dishes or troughs and lines to transport fluids to the power station. These systems were analyzed at a rated capacity of 30 MW of thermal energy delivered in the form of superheated steam at 538 C (1000 F) and 68 atm (1000 psia), using consistent weather data, collector surface waviness, pointing error, and electric conversion efficiency. The comparisons include technical considerations for component requirements, land utilization, and annual thermal energy collection rates. The relative merits of different representative systems are dependent upon the overall conversion as expressed in the form of performance factors in this paper. These factors are essentially indices of the relative performance effectiveness for different concepts based upon unit collector area. These performance factors enable further economic tradeoff studies of systems to be made by comparing them with projected production costs for these systems.

Wen, L.↗

NASA NTRS1976

Thermal model for impact breccia lithification - Manicouagan and the moon

The thermal model of Simonds (1975) is extended to the full spectrum of impact-produced rocks ranging from fragmental breccias to impact melts, with reference to the Manicouagan impact structure in Quebec. This is done by relating the basic textural features of impact-lithified rocks to variations in the mixture of superheated impact-fused material originating near the point of impact and much cooler fragmented debris originating farther from the point of impact.

Simonds, C. H.↗

NASA NTRS1978

Fabrication and test of a variable conductance heat pipe

A variable conductance heat pipe (VCHP) with feedback control was fabricated with a reservoir-condenser volume ratio of 10 and an axially grooved action section. Tests of the heat transport capability were greater than or equal to the analytical predictions for the no gas case. When gas was added, the pipe performance degraded by 18% at zero tilt as was expected. The placement of the reservoir heater and the test fixture cooling fins are believed to have caused a superheated vapor condition in the reservoir. Erroneously high reservoir temperature indications resulted from this condition. The observed temperature gradients in the reservoir lend support to this theory. The net result was higher than predicted reservoir temperatures. Also, significant increases in minimum heat load resulted for controller set point temperatures higher than 0 C. At 30 C, control within the tolerance band was maintained, but high reservoir heater power was required. Analyses showed that control is not possible for reasonably low reservoir heater power. This is supported by the observation of a significant reservoir heat leak through the condenser.

Lehtinen, A. M.↗

NASA NTRS1978

Gas core reactors for actinide transmutation and breeder applications

This work consists of design power plant studies for four types of reactor systems: uranium plasma core breeder, uranium plasma core actinide transmuter, UF6 breeder and UF6 actinide transmuter. The plasma core systems can be coupled to MHD generators to obtain high efficiency electrical power generation. A 1074 MWt UF6 breeder reactor was designed with a breeding ratio of 1.002 to guard against diversion of fuel. Using molten salt technology and a superheated steam cycle, an efficiency of 39.2% was obtained for the plant and the U233 inventory in the core and heat exchangers was limited to 105 Kg. It was found that the UF6 reactor can produce high fluxes (10 to the 14th power n/sq cm-sec) necessary for efficient burnup of actinide. However, the buildup of fissile isotopes posed severe heat transfer problems. Therefore, the flux in the actinide region must be decreased with time. Consequently, only beginning-of-life conditions were considered for the power plant design. A 577 MWt UF6 actinide transmutation reactor power plant was designed to operate with 39.3% efficiency and 102 Kg of U233 in the core and heat exchanger for beginning-of-life conditions.

Clement, J. D.↗

NASA NTRS1978

Waste heat utilization in industrial processes

A survey is given of new developments in heat exchangers and heat pumps. With respect to practical applications, internal criteria for plant operation are discussed. Possibilities of government support are pointed out. Waste heat steam generators and waste heat aggregates for hot water generation or in some cases for steam superheating are used. The possibilities of utilization can be classified according to the economic improvements and according to their process applications, for example, gascooling. Examples are presented for a large variety of applications.

Weichsel, M.↗

NASA NTRS1977

Large-scale thermal energy storage using sodium hydroxide /NaOH/

A technique employing NaOH phase change material for large-scale thermal energy storage to 900 F (482 C) is described; the concept consists of 12-foot diameter by 60-foot long cylindrical steel shell with closely spaced internal tubes similar to a shell and tube heat exchanger. The NaOH heat storage medium fills the space between the tubes and outer shell. To charge the system, superheated steam flowing through the tubes melts and raises the temperature of NaOH; for discharge, pressurized water flows through the same tube bundle. A technique for system design and cost estimation is shown. General technical and economic properties of the storage unit integrated into a solar power plant are discussed.

Turner, R. H.↗

NASA NTRS1978

Shape of two-dimensional solidification interface during directional solidification by continuous casting

An analysis was made of the two-dimensional solidification of an ingot being cooled and withdrawn vertically downward from a mold consisting of parallel walls of finite length. Heat transfer analysis shows how the flatness of the interface is related to the ingot thickness, the withdrawal rate, the heat addition from the superheated liquid metal, and the temperature difference available for cooling. This provides an understanding of the conditions that will yield a maximum rate of casting while achieving the desired flatness of the interface. The results are interpreted with respect to the conditions for obtaining an aligned eutectic structure by directional solidification. In this process an additional constraint must be included that relates the ingot withdrawal rate and the heat transfer rate from the liquid metal to the solidification interface.

Siegel, R.↗

NASA NTRS1978

Investigation of the Manicouagan impact crater, Quebec - An introduction

An interdisciplinary study of the 65-km diameter Manicouagan ring structure in Quebec was undertaken to gain insight into the integrated effects of impacts on terrestrial planetary bodies. The paper serves as an introduction to several companion papers and summarizes major conclusions. Studies of the 214 m.y. old structure show that the melt rocks are texturally inhomogeneous but chemically homogeneous and can be modeled as a mixture of target lithologies. The melt rocks have a Sr-87/Sr-86 ratio compatible with the melting of crustal rocks. The melt had a two-stage cooling history with clast-melt interactions indicative of mixing superheated silicate liquid with cold clasts. Grain size, clast reactions, and thermal equilibration of clasts and melts are described.

Phinney, W. C.↗

NASA NTRS1978

The thermal history of the Manicouagan impact melt sheet, Quebec

Calculations for the heat transfer between superheated silicate melt and evenly dispersed 1-mm cold clasts indicate that most of the thermal gradients are smoothed out in 100 s and that the rate of equilibrium is sufficiently high so that clasts whose dissolution in the melt is slow may be preserved. The calculations also show the extent to which cold debris and clasts are melted. Calculations for cooling of the 200-m-thick melt sheet at Manicouagan suggest that complete crystallization takes 35 years at 10 m from the edge and 1600 years at the center.

Onorato, P. I. K.↗

NASA NTRS1977

Apollo 14 revisited, or breccias aren't so bad after all

A study of large Apollo 14 samples suggests that they were formed by the same processes which formed the impactites found at Apollo 16 and 17 and in terrestrial craters, especially those in crystalline targets. The abundant crystalline matrix breccias of the Apollo 14 samples generally show higher clast contents and less refractory clast populations than the clast-laden impact melts abundant at the other Apollo nonmare landing sites. The Apollo 14 characteristics are attributed to the mixing of a greater amount of cold clastic debris into the superheated melt formed during impacts. The other major lithology at Apollo 14, the vitric matrix breccias, are made in part from agglutinate-bearing soil and cannot be the protolith of crystalline matrix breccias, because of differences in structure and composition. Variations among the breccias indicate the occurrence of several impact events.

Simonds, C. H.↗