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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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Gas phase ion-molecule phosphine reactions in pure and binary mixtures by ion cyclotron resonance spectroscopy, considering acidity and basicity
Laser Doppler velocimeter, determining basic operational parameters including required particle density, number, type, size, output signal to noise ratio, etc
Linear mountain lee wave model with nonlinear lower boundary condition for arbitrary basic flow and two dimensional topography, computing flow field
The basic elements of a systems engineering process are given along with a detailed description of what the safety system requires from the systems engineering process. Also discussed is the safety that the system provides to other subfunctions of systems engineering.
Current research is reported on precise and accurate descriptions of the earth's surface and gravitational field and on time variations of geophysical parameters. A new computer program was written in connection with the adjustment of the BC-4 worldwide geometric satellite triangulation net. The possibility that an increment to accuracy could be transferred from a super-control net to the basic geodetic (first-order triangulation) was investigated. Coordinates of the NA9 solution were computed and were transformed to the NAD datum, based on GEOS 1 observations. Normal equations from observational data of several different systems and constraint equations were added and a single solution was obtained for the combined systems. Transformation parameters with constraints were determined, and the impact of computers on surveying and mapping is discussed.
The vehicle related data developed during the orbital operations study are described. The interfacing activity findings have been realigned into the four basic vehicle systems as follows: (1) earth orbital shuttle (EOS), (2) research and applications module (RAM), (3) space based, ground based, manned and unmanned tugs, and (4) modular space station (MSS).
A method is presented which can be used to map silicate rock-type from aerial infrared data. The method has been partially tested over a sand quarry at Mill Creek, Oklahoma, in which highly siliceous targets were discriminated from nonsilicates in the scene. The technique is currently being tested experimentally on basic silicates. On the basis of the Mill Creek results and theoretical considerations, percent SiO2 differences as small as 14% should be detectable with the University of Michigan's currently available detectors.
Development of a basic set of normalized parameters to represent low-thrust system characteristics. The conditions which must be met to obtain trajectory and performance data which are invariant with the launch vehicle characteristics, the selected power, the specific mass of the low-thrust vehicle, and the efficiency of the ion propulsion system are derived. This normalized representation of mission characteristics frees the analyst from having to rerun the trajectories if any of the aforementioned parameters are varied. Examples pertaining to a low-thrust Jupiter flyby and comet Encke rendezvous are given to demonstrate the utility of the method of presentation.
An understanding of the principles which govern variable speed drive operation is discussed for successful drive application. The fundamental factors of torque, speed ratio, and power as they relate to drive selection are discussed. The basic types of variable speed drives, their operating characteristics and their applications are also presented.
The author has identified the following significant results. It was found that seven basic cloud types could be detected from ERTS-1 imagery. Each type exhibited characteristics that made them distinct. Suitable examples of each type were chosen, described, and a cloud identification item-index key prepared.
A discussion of the basic measures of corporate financial strength, and the sources of the information is reported. Considered are: balance sheet, income statement, funds and cash flow, and financial ratios.
The basic available types of variable speed drive systems are described in terms of operating characteristics and typical applications. The fundamental factors of torque, speed ratio, and power are discussed as they relate to drive selection, and the use of a systems approach is urged in the choice and development of a variable speed drive train.
Thermal cycling studies on cermets prepared from tungsten and UO2 powder mixtures and cermets prepared using tungsten coated UO2 particles are discussed. The cermets were tested in hydrogen at high temperatures to determine the effects of temperature, thermal cycling, and hydrogen pressure. Basic mechanism studies of tungsten-UO2 interactions in thermally cycled cermets are also described.
The results of an experimental study of off-center-line shock-interference heating on basic shapes at hypersonic speeds are presented. The study covered three types of shock-interference patterns over a range of nominal Mach numbers (6 to 20), specific heat ratios (1.40 and 1.67), free-stream Reynolds numbers(8 million to 26 million per meter), and impinging shock strengths. Heat-transfer rates higher than stagnation levels were measured over much of the off-center-line model surface. Peak heating up to 17 times the stagnation heating was measured.
The basic elements of power spectral analysis with emphasis on the Blackman-Tukey method are presented. Short discussions are included on the topics of pre-whitening, frequency and spectral windows, and statistical reliability. Examples are included whenever possible, and a FORTRAN subroutine for calculating a power spectrum is presented.
A research program has been conducted to determine the degree of cruise drag correlation on the C-141A aircraft between predictions based on wind tunnel test data, and flight test results. Information is presented on the wind tunnel test program and basic aerodynamic data on the C-141A wind-tunnel model used in the correlation studies.
Construction and electrical characterization of the 4096 x 2-bit Basic Memory Module (BMM) are reported for the Space Ultrareliable Modular Computer (SUMC) program. The module uses four 2K x 1-bit N-channel FET, random access memory chips, called array chips, and two sense amplifier chips, mounted and interconnected on a ceramic substrate. Four 5% tolerance power supplies are required. At the Module, the address, chip select, and array select lines require a 0-8.5 V MOS signal level. The data output, read-strobe, and write-enable lines operate at TTl levels. Although the module is organized as 4096 x 2 bits, it can be used in a 8196 x 1-bit application with appropriate external connections. A 4096 x 1-bit organization can be obtained by depopulating chips.
Aeronautical design engineering for general aviation aircraft considers the iteration of wind tunnel test data are lift, weight, drag, and thrust as the basic balancing factor in drag reduction efforts.