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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS1996

Web interfaces to relational databases

This reports on a project to extend the capabilities of a Virtual Research Center (VRC) for NASA's Advanced Concepts Office. The work was performed as part of NASA's 1995 Summer Faculty Fellowship program and involved the development of a prototype component of the VRC - a database system that provides data creation and access services within a room of the VRC. In support of VRC development, NASA has assembled a laboratory containing the variety of equipment expected to be used by scientists within the VRC. This laboratory consists of the major hardware platforms, SUN, Intel, and Motorola processors and their most common operating systems UNIX, Windows NT, Windows for Workgroups, and Macintosh. The SPARC 20 runs SUN Solaris 2.4, an Intel Pentium runs Windows NT and is installed on a different network from the other machines in the laboratory, a Pentium PC runs Windows for Workgroups, two Intel 386 machines run Windows 3.1, and finally, a PowerMacintosh and a Macintosh IIsi run MacOS.

Carlisle, W. H.↗
NASA NTRS1996

Scheduled Civil Aircraft Emission Inventories for 1976 and 1984: Database Development and Analysis

This report describes the development of a three-dimensional database of aircraft fuel burn and emissions (fuel burned, NOx, CO, and hydrocarbons) from scheduled commercial aircraft for four months (February, May, August, and November) of 1976 and 1984. Combining this data with earlier published data for 1990 and 1992, trend analyses for fuel burned, NOx, carbon monoxide, and hydrocarbons were calculated for selected regions (global, North America, Europe, North Atlantic, and North Pacific). These emissions inventories are available for use by atmospheric scientists conducting the Atmospheric Effects of Aviation Project (AEAP) modeling studies. Fuel burned and emissions of nitrogen oxides (NOx as NO2), carbon monoxide, and hydrocarbons have been calculated on a 1 degree latitude x 1 degree longitude x 1 kilometer altitude grid and delivered to NASA as electronic files.

Baughcum, Steven L.↗
NASA NTRS1996

Scheduled civil aircraft emission inventories for 1992: Database development and analysis

This report describes the development of a three-dimensional database of aircraft fuel burn and emissions (fuel burned, NOx, CO, and hydrocarbons) from scheduled commercial aircraft for each month of 1992. The seasonal variation in aircraft emissions was calculated for selected regions (global, North America, Europe, North Atlantic, and North Pacific). A series of parametric calculations were done to quantify the possible errors introduced from making approximations necessary to calculate the global emission inventory. The effects of wind, temperature, load factor, payload, and fuel tankering on fuel burn were evaluated to identify how they might affect the accuracy of aircraft emission inventories. These emissions inventories are available for use by atmospheric scientists conducting the Atmospheric Effects of Aviation Project (AEAP) modeling studies. Fuel burned and emissions of nitrogen oxides (NOx as N02), carbon monoxide, and hydrocarbons have been calculated on a 1 degree latitude x 1 degree longitude x 1 kilometer altitude grid and delivered to NASA as electronic files.

Baughcum, Steven L.↗
NASA NTRS1996

Studying Turbulence Using Numerical Simulation Databases: Proceedings of the 1996 Summer Program - Part 6

Topics considered include: New approach to turbulence modeling; Second moment closure analysis of the backstep flow database; Prediction of the backflow and recovery regions in the backward facing step at various Reynolds numbers; Turbulent flame propagation in partially premixed flames; Ensemble averaged dynamic modeling. Also included a study of the turbulence structures of wall-bounded shear flows; Simulation and modeling of the elliptic streamline flow.

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NASA NTRS1996

Evaluation of a vortex-based subgrid stress model using DNS databases

The performance of a SubGrid Stress (SGS) model for Large-Eddy Simulation (LES) developed by Misra k Pullin (1996) is studied for forced and decaying isotropic turbulence on a 32(exp 3) grid. The physical viability of the model assumptions are tested using DNS databases. The results from LES of forced turbulence at Taylor Reynolds number R(sub (lambda)) approximately equals 90 are compared with filtered DNS fields. Probability density functions (pdfs) of the subgrid energy transfer, total dissipation, and the stretch of the subgrid vorticity by the resolved velocity-gradient tensor show reasonable agreement with the DNS data. The model is also tested in LES of decaying isotropic turbulence where it correctly predicts the decay rate and energy spectra measured by Comte-Bellot & Corrsin (1971).

Misra, Ashish↗
NASA NTRS1996

Hydroacoustic forcing function modeling using DNS database

A wall pressure frequency spectrum model (Blake 1971 ) has been evaluated using databases from Direct Numerical Simulations (DNS) of a turbulent boundary layer (Na & Moin 1996). Good agreement is found for moderate to strong adverse pressure gradient flows in the absence of separation. In the separated flow region, the model underpredicts the directly calculated spectra by an order of magnitude. The discrepancy is attributed to the violation of the model assumptions in that part of the flow domain. DNS computed coherence length scales and the normalized wall pressure cross-spectra are compared with experimental data. The DNS results are consistent with experimental observations.

Zawadzki, I.↗
NASA NTRS1997

Comparison of Stopping Power and Range Databases for Radiation Transport Study

The codes used to calculate stopping power and range for the space radiation shielding program at the Langley Research Center are based on the work of Ziegler but with modifications. As more experience is gained from experiments at heavy ion accelerators, prudence dictates a reevaluation of the current databases. Numerical values of stopping power and range calculated from four different codes currently in use are presented for selected ions and materials in the energy domain suitable for space radiation transport. This study of radiation transport has found that for most collision systems and for intermediate particle energies, agreement is less than 1 percent, in general, among all the codes. However, greater discrepancies are seen for heavy systems, especially at low particle energies.

Tai, H.↗
NASA NTRS1996

A Database for Propagation Models and Conversion to C++ Programming Language

The telecommunications system design engineer generally needs the quantification of effects of the propagation medium (definition of the propagation channel) to design an optimal communications system. To obtain the definition of the channel, the systems engineer generally has a few choices. A search of the relevant publications such as the IEEE Transactions, CCIR's, NASA propagation handbook, etc., may be conducted to find the desired channel values. This method may need excessive amounts of time and effort on the systems engineer's part and there is a possibility that the search may not even yield the needed results. To help the researcher and the systems engineers, it was recommended by the conference participants of NASA Propagation Experimenters (NAPEX) XV (London, Ontario, Canada, June 28 and 29, 1991) that a software should be produced that would contain propagation models and the necessary prediction methods of most propagation phenomena. Moreover, the software should be flexible enough for the user to make slight changes to the models without expending a substantial effort in programming. In the past few years, a software was produced to fit these requirements as best as could be done. The software was distributed to all NAPEX participants for evaluation and use, the participant reactions, suggestions etc., were gathered and were used to improve the subsequent releases of the software. The existing database program is in the Microsoft Excel application software and works fine within the guidelines of that environment, however, recently there have been some questions about the robustness and survivability of the Excel software in the ever changing (hopefully improving) world of software packages.

Kantak, Anil V.↗
NASA NTRS1999

One for All: Maintaining a Single Schedule Database for Large Development Projects

Efficiently maintaining and controlling a single schedule database in an Integrated Product Team environment is a significant challenge. It's accomplished effectively with the right combination of tools, skills, strategy, creativity, and teamwork. We'll share our lessons learned maintaining a 20,000 plus task network on a 36 month project.

Hilscher, R.↗
NASA NTRS2000

Launch Vehicle Mass Estimating Relationship Database

This document is a printout of the contents of a database designed to estimate the mass for a launch vehicle. The Mass Estimating Relationship (MER) is given for specific parts of a launch vehicle.

Brothers, Bobby↗
NASA NTRS1999

An Experimental Database for Conventional and Alternate Control Concepts on the HSR 1.675% Reference H Model

The objective was to experimentally evaluate the longitudinal and lateral-directional stability and control characteristics of the Reference H configuration at supersonic and transonic speeds. A series of conventional and alternate control devices were also evaluated at supersonic and transonic speeds. A database on the conventional and alternate control devices was to be created for use in the HSR program.

McMillin, Naomi↗
NASA NTRS2000

Thermal and Evolved Gas Analyses at Reduced Pressures: A Mineral Database for the Thermal Evolved Gas Analyzer (TEGA)

Volatile-bearing minerals (e.g., Fe-oxyhydroxides, phyllosilicates, carbonates, and sulfates) may be important phases on the surface of Mars. The Thermal Evolved Gas Analyzer (TEGA), which was part of the Mars Polar Lander payload, was to detect and identify volatile-bearing phases in the Martian regolith. The TEGA instrument is composed of a differential scanning calorimetry (DSC) interfaced with an evolved gas analyzer (EGA). The EGA consists of a Herriott cell of a tunable-diode laser (TDL) spectrometer that determines CO, and H2O abundances. The sample chamber in TEGA operates at about 100 mbar (-76 torr) with a N2 carrier gas flow of 0.4 sccm. Essentially no information exists on the effects of reduced pressure on the thermal properties of volatile-bearing minerals. Here we present a database for the thermal behavior of volatile-bearing phases under reduced pressure conditions.

Lauer, H. V., Jr.↗
NASA NTRS2001

Parametric Fin-Body and Fin-Plate Database for a Series of 12 Missile Fins

A cooperative experimental investigation has been performed to obtain a systematic fin-body and fin-plate database for a series of 12 missile fins. These data are intended to complement and extend the information contained in the Triservice missile project and to provide a systematic set of experimental data from which fin-body interference factors can be derived. Data were obtained with the fins mounted on both an axisymmetric body and on a flat plate that was used to simulate fin-alone measurements. The experiments were conducted at Mach numbers from 0.60 to 3.95; fin deflection angles of 0 deg, 10 deg, and -10 deg; and angles of attack up to 30 deg on the body and up to 95 deg on the flat plate. The data were obtained from three-component balances attached to the fins and a six-component balance located in the axisymmetric body. The data obtained in this project are documented in tabular form in this report. In addition, selected data are presented in graphical form to illustrate the effects of the test variables. These variables are configuration angle of attack; Mach number; and fin parameters of deflection angle, planform size, taper ratio, and aspect ratio. A very limited comparison with the Triservice missile data is made to illustrate the consistency between the data from these two projects.

Allen, Jerry M.↗
NASA NTRS2001

An Updated Database of Coronae on Venus

We present an updated database of coronae on Venus, increasing the number of features from 336 to 523. Additional information is contained in the original extended abstract.

Stofan, E. R.↗
NASA NTRS2001

Satellite Communications Technology Database

The Satellite Communications Technology Database is a compilation of data on state-of-the-art Ka-band technologies current as of January 2000. Most U.S. organizations have not published much of their Ka-band technology data, and so the great majority of this data is drawn largely from Japanese, European, and Canadian publications and Web sites. The data covers antennas, high power amplifiers, low noise amplifiers, MMIC devices, microwave/IF switch matrices, SAW devices, ASIC devices, power and data storage. The data herein is raw, and is often presented simply as the download of a table or figure from a site, showing specified technical characteristics, with no further explanation.

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