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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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Report includes many charts that present graphically the effects of design parameters on performance. Equations and data are given which can assist designer in selecting among such factors as working medium, horsepower, and engine components.
Analysis and design of the LASER Aerodynamic Satellite was performed and the design integrated with the launch vehicle interfaces and launch operations. The satellite has a requirement to be compatible with techniques for ranging from earth to satellite to an accuracy of + or - sq cm. The results indicate the satellite design while maintaining low program cost, met the design and mission requirements. Trade studies and satellite design are documented along with thermal and optical tests.
Report details technique for measuring total body calcium by collecting exhaled 37Ar gas after exposure of patients to 14-MeV neutrons. Summary for theoretical basis of technique is presented.
The Shaberth bearing analysis computer program was developed for the analysis of jet engine shaft/bearing systems operating above room temperature with normal hydrocarbon lubricants. It is also possible to use this tool to evaluate the shaft bearing systems operating in cryogenics. Effects such as fluid drag, radial temperature gradients, outer race misalignments and clearance changes were simulated and evaluated. In addition, the speed and preload effects on bearing radial stiffness was evaluated. The Shaberth program was also used to provide contact stresses from which contact geometry was calculated to support other analyses such as the determination of cryogenic fluid film thickness in the contacts and evaluation of surface and subsurface stresses necessary for bearing failure evaluation. This program was a vital tool for the thermal analysis of the bearing in that it provides the heat generation rates at the rolling element/race contacts for input into a thermal model of the bearing/shaft assembly.
Report analyzes the stresses in a fuselage of the built-up type in which the shear is taken by diagonal bracing wires. Tests are conducted for landing, flying, and thrust loads.
Report presents study of finite-element mathematical modeling as used in analyzing stresses and strains at joints between thin, shell-like components (e.g., ducts) and thicker components (e.g., flanges or engine blocks). First approach uses global/local model to evaluate system. Provides correct total response and correct representation of stresses away from any discontinuities. Second approach involves development of special transition finite elements to model transitions between shells and thicker structural components.
Reported here is a summary of studies examining some problems in an energy conversion system. Regenerative fuel cell systems have been suggested for future manned space missions, but to meet the needed specific power requirements substantial improvements in the state-of-the-art technologies are needed. Similar improvements are needed, with emphasis on cost reduction in addition to higher conversion efficiency, for fuel cell systems that have potential for terrestrial applications. Polymer Electrolyte Membrane (PEM) fuel cells have been identified as promising candidates for development that would lead to the desired cost reduction and increased efficiency.
Reported here is a summary of studies examining some problems in an energy conversion system. Regenerative fuel cell systems have been suggested for future manned space missions, but to meet the needed specific power requirements substantial improvements in the state-of-the-art technologies are needed. Similar improvements are needed, with emphasis on cost reduction in addition to higher conversion efficiency, for fuel cell systems that have potential for terrestrial applications. Polymer electrolyte membrane (PEM) fuel cells have been identified as promising candidates for development that would lead to the desired cost reduction and increased efficiency.
Voyager project - mission and system tradeoff studies, trajectory analysis, orbit and landing site selection, reliability, and sterilization
Application of variational calculus to trajectory analysis of multistage vehicle
Applying calculus of variations to multistage rocket trajectory analysis
Characteristics and trajectory analysis of solar electric propulsion space missions - Mars orbiter and Jupiter flyby
Tests and analysis of nimbus-D storage module
This report summarizes the activity of the Italian INAF VLBI Analysis Center. Our Analysis Center is located in Bologna, Italy and belongs to the Institute of Radioastronomy, which is part of the National Institute of Astrophysics. IRA runs the observatories of Medicina and Noto, where two 32-m VLBI AZ-EL telescopes are situated. This report contains the AC's VLBI data analysis activities and shortly outlines the investigations into the co-locations of space geodetic instruments.
Digital computer aided circuit analysis and design
Quality control failure analysis on silicon microcircuit structures
Nonstationary adjoint statistical wind model for flight control systems analysis
Studies related to Pioneer 8 and 9 data tape analysis