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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Desiccant humidity control system

A water vapor and carbon dioxide sorbent material (designated HS-C) was developed for potential application to the space shuttle and tested at full scale. Capacities of two percent for carbon dioxide and four percent for water vapor were achieved using space shuttle cabin adsorption conditions and a space vacuum for desorption. Performance testing shows that water vapor can be controlled by varying the air process flow, while maintaining the ability to remove carbon dioxide. A 2000 hour life test was successfully completed, as were tests for sensitivity to cleaning solvent vapors, vibration resistance, and flammability. A system design for the space shuttle shows a 200 pound weight advantage over competitive systems and an even larger advantage for longer missions.

Lunde, P. J.↗
NASA NTRS1975

Tug fleet and ground operations schedules and controls. Volume 1: Executive summary

This study presents Tug Fleet and Ground Operations Schedules and Controls plan. This plan was developed and optimized out of a combination of individual Tug program phased subplans, special emphasis studies, contingency analyses and sensitivity analyses. The subplans cover the Tug program phases: (1) Tug operational, (2) Interim Upper Stage (IUS)/Tug fleet utilization, (3) and IUS/Tug payload integration, (4) Tug site activation, (5) IUS/Tug transition, (6) Tug acquisition. Resource requirements (facility, GSE, TSE, software, manpower, logistics) are provided in each subplan, as are appropriate Tug processing flows, active and total IUS and Tug fleet requirements, fleet management and Tug payload integration concepts, facility selection recommendations, site activation and IUS to Tug transition requirements. The impact of operational concepts on Tug acquisition is assessed and the impact of operating Tugs out of KSC and WTR is analyzed and presented showing WTR as a delta. Finally, cost estimates for fleet management and ground operations of the DDT&E and operational phases of the Tug program are given.

Source record↗
NASA NTRS1975

Physical nature of the climatic and biological effects of the Peru current

Surface and depth flow processes and their effects on the behavior of the Peru current are considered in relation to climatological and biological effects for the entire western coast of South America. The mean annual coastal air temperature is from 2 deg to 6 deg below the norm and precipitation is extremely rare. An upwelling effect brings up the cold deep waters with their rich content of organic material responsible for the huge biological productivity of the region.

Gusev, A. M.↗
NASA NTRS1974

Skylab S-193 altimeter experiment performance, results and applications

A description of the Skylab altimeter instrument system along with the appropriate system error model is presented. The data processing flow, orbit computation, and topographic recovery techniques are discussed. Some data analysis results are presented which indicate excellent correlation with underwater topographic features. In addition, results are shown which indicate that the instrument performance was as expected.

Mcgoogan, J. T.↗
NASA NTRS1975

Ispra Mark-10 water splitting process

A thermochemical water splitting process, the Ispra Mark-10 chemical reaction cycle, was chosen for examining the possibility of using water to produce hydrogen on a large scale for fuel and major industrial chemical uses. The assumed energy source for the process is an HTGR (helium cooled). A process flow diagram, a material balance, and an energy balance were developed for the thermochemical reaction cycle. Principal reactions which constitute the cycle are included.

Source record↗
NASA NTRS1976

Formulation of detailed consumables management models for the development (preoperational) period of advanced space transportation system. Volume 1: Detailed requirements for the mission planning processor

Detailed requirements for the mission planning processor are documented. The mission planning processor is a user oriented tool for consumables management and is part of the total consumables subsystem management concept. A quasi top-down approach was applied to the design of the mission planning processor. Interface requirements, input/output, and data base concepts were considered before computational processing. Existing analytical models were investigated for applicability before new models were developed. The mission planning processor was designed for an interactive system using demand terminals for input/outputdisplay and interfacing with an updateable mission data bank. The control and support routines provide the user interface, peripheral data handling, program control, and support functions required by the mission planning processor for execution on an interactive system. A description, interface requirements, definition of internal variables, listing of input data, processing flow diagram, and listing of output data are presented for each routine.

Connelly, L. C.↗
NASA NTRS1977

Elasto-plastic flow in cracked bodies using a new finite element model

Cracked geometries were studied by finite element techniques with the aid of a new special element embedded at the crack tip. This model seeked to accurately represent the singular stresses and strains associated with the elasto-plastic flow process. The present model was not restricted to a material type and did not predetermine a singularity. Rather the singularity was treated as an unknown. For each step of the incremental process the nodal degrees of freedom and the unknown singularity were found through minimization of an energy-like functional. The singularity and nodal degrees of freedom were determined by means of an iterative process.

Karabin, M. E., Jr.↗
NASA NTRS1978

Experimental study of the laminar-turbulent transition of a concave wall in a parallel flow

The instability of the laminar boundary layer flow along a concave wall was studied. Observations of these three-dimensional boundary layer phenomena were made using the hydrogen-bubble visualization technique. With the application of stereo-photogrammetric methods in the air-water system it was possible to investigate the flow processes qualitatively and quantitatively. In the case of a concave wall of sufficient curvature, a primary instability occurs first in the form of Goertler vortices with wave lengths depending upon the boundary layer thickness and the wall curvature. At the onset the amplification rate is in agreement with the linear theory. Later, during the non-linear amplification stage, periodic spanwise vorticity concentrations develop in the low velocity region between the longitudinal vortices. Then a meandering motion of the longitudinal vortex streets subsequently ensues, leading to turbulence.

Bippes, H.↗
NASA NTRS1978

Measurements of noise produced by flow past lifting surfaces

Wind tunnel studies have been conducted to determine the specific locations of aerodynamic noise production within the flow field about various lifting-surface configurations. The models tested included low aspect ratio shapes intended to represent aircraft flaps, a finite aspect ratio NACA 0012 wing, and a multi-element wing section consisting of a main section, a leading edge flap, and dual trailing edge flaps. Turbulence was induced on the models by surface roughness. Lift and drag were measured for the flap models. Hot-wire anemometry was used for study of the flap-model vortex roll-up. Apparent noise source distributions were measured by use of a directional microphone system, located outside the tunnel, which was scanned about the flow region to be analyzed under computer control. These distributions exhibited a diversity of pattern, suggesting that several flow processes are important to lifting-surface noise production. Speculation concerning these processes is offered.

Kendall, J. M.↗
NASA NTRS1979

Nonsteady-Flow Thrust Augmenting Ejectors

Ejector augmenters in which the transfer of mechanical energy from the primary to the secondary flow takes place through the work of interface pressure forces are investigated. Nonsteady flow processes are analyzed from the standpoint of energy transfer efficiency and a comparison of a rotary jet augmenter to an ejector is presented.

Foa, J. V.↗
NASA NTRS1980

Thermal energy storage systems using fluidized bed heat exchangers

A rotary cement kiln and an electric arc furnace were chosen for evaluation to determine the applicability of a fluid bed heat exchanger (FBHX) for thermal energy storage (TES). Multistage shallow bed FBHX's operating with high temperature differences were identified as the most suitable for TES applications. Analysis of the two selected conceptual systems included establishing a plant process flow configuration, an operational scenario, a preliminary FBHX/TES design, and parametric analysis. A computer model was developed to determine the effects of the number of stages, gas temperatures, gas flows, bed materials, charge and discharge time, and parasitic power required for operation. The maximum national energy conservation potential of the cement plant application with TES is 15.4 million barrels of oil or 3.9 million tons of coal per year. For the electric arc furnance application the maximum national conservation potential with TES is 4.5 million barrels of oil or 1.1 million tons of coal per year. Present time of day utility rates are near the breakeven point required for the TES system. Escalation of on-peak energy due to critical fuel shortages could make the FBHX/TES applications economically attractive in the future.

Weast, T.↗
NASA NTRS1981

Silicon production process evaluations

The chemical engineering analysis of the preliminary process design of a process for producing solar cell grade silicon from dichlorosilane is presented. A plant to produce 1,000 MT/yr of silicon is analyzed. Progress and status for the plant design are reported for the primary activities of base case conditions (60 percent), reaction chemistry (50 percent), process flow diagram (35 percent), energy balance (10 percent), property data (10 percent) and equipment design (5 percent).

Source record↗
NASA NTRS1981

IGDS/TRAP Interface Program (ITIP). Software User Manual (SUM)

This specification establishes the requirements, concepts, and preliminary design for a set of software known as the IGDS/TRAP Interface Program (ITIP). This software provides the capability to develop at an Interactive Graphics Design System (IGDS) design station process flow diagrams for use by the NASA Coal Gasification Task Team. In addition, ITIP will use the Data Management and Retrieval System (DMRS) to maintain a data base from which a properly formatted input file to the Time-Line and Resources Analysis Program (TRAP) can be extracted. This set of software will reside on the PDP-11/70 and will become the primary interface between the Coal Gasification Task Team and IGDS, DMRS, and TRAP. The user manual for the computer program is presented.

Jefferys, S.↗
NASA NTRS1982

Low-Waste Purification of Silicon

Ultra-high-purity silicon required for solar cells, transistors and integrated circuits can be produced from metallurgical grade silicon by formation and pyrolysis of silane gas in continuous-flow process that maximizes product purity with minimum amount of equipment. Integrated process recycles unreacted and byproduct materials, minimizing material losses and simplifying waste disposal. Ensures effective removal of impurities, including boron.

Breneman, W. C.↗
NASA NTRS1981

Development of an advanced Sabatier CO2 reduction subsystem

A preprototype Sabatier CO2 reduction subsystem was successfully designed, fabricated and tested. The lightweight, quick starting (less than 5 minutes) reactor utlizes a highly active and physically durable methanation catalyst composed of ruthenium on alumina. The use of this improved catalyst permits a simple, passively controlled reactor design with an average lean component H2/CO2 conversion efficiency of over 99% over a range of H2/CO2 molar ratios of 1.8 to 5 while operating with process flows equivalent to a crew size of up to five persons. The subsystem requires no heater operation after start-up even during simulated 55 minute lightside/39 minute darkside orbital operation.

Kleiner, G. N.↗
NASA NTRS1982

Time resolved density measurements in premixed turbulent flames

Premixed, turbulent flames are important in connection with investigations of fundamental, turbulent-reacting-flow processes and the study of practical combustion devices, such as spark ignition engines and premixed, prevaporized gas turbine combustors which burn premixed reactants. The considered investigation is concerned with the application of laser induced Rayleigh scattering to measure the gas density in premixed, methane-air flames. A description is provided of the results of density and velocity measurements in an open, lean, premixed methane-air flame stabilized in grid turbulence of low Reynolds number. It is found that where applicable, Rayleigh scattering can be used to good advantage to measure molecular number density. Mean and rms density results show that the mean flame thickens with axial distance but that the maximum in rms does not change appreciably.

Dandekar, K. V.↗
NASA NTRS1980

View angle effects in the radiometric measurement of plant canopy temperatures

The thermal infrared sensor response from a wheat canopy was extremely non-Lambertian because of spatial variations in energy flow processes; the effective radiant temperature of the sensor varied as much as 13 C with changing view angle. This variation of sensor response was accurately quantified (root-mean-square of deviations between theoretical and measured responses reduced to 1.1 C) as a function of vegetation canopy geometry, vertical temperature distribution of canopy components, and sensor view angle. The results have important implications for optimizing sensor view angles for remote sensing missions.

Kimes, D. S.↗
NASA NTRS1982

Measurement and visualization of skin friction on the leeside of delta wings in supersonic flow

The reported investigation was conducted with the aid of the NASA Ames High Reynolds Number Wind Tunnel. The flow conditions considered involved free stream Mach numbers of 2 and 3, and a Reynolds number of approximately 10,000,000 p. m. The employed model was a delta wing with an angle of 70 deg. A method reported by Tanner (1977) was used for the measurement of the skin friction. This method involves the use of a laser interferometer to determine the change in the thickness of an oil film. The procedure can also be employed for a visualization of skin friction in the form of interferograms. The investigation shows that skin friction measurements can provide a significant contribution to a physical understanding of the flow processes at the delta wing.

Szodruch, J.↗