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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 1,189 records · Page 66
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

IMP: Interactive mass properties program. Volume 1: Program description

A method of computing a weights and center of gravity analysis of a flight vehicle using interactive graphical capabilities of the Adage 340 computer is described. The equations used to calculate area, volume, and mass properties are based on elemental surface characteristics. The input/output methods employ the graphic support of the Adage computer. Several interactive program options are available for analyzing the mass properties of a vehicle. These options are explained.

Stewart, W. A.↗
NASA NTRS1978

Multispectral scanner system parameter study and analysis software system description, volume 2

The author has identified the following significant results. The integration of the available methods provided the analyst with the unified scanner analysis package (USAP), the flexibility and versatility of which was superior to many previous integrated techniques. The USAP consisted of three main subsystems; (1) a spatial path, (2) a spectral path, and (3) a set of analytic classification accuracy estimators which evaluated the system performance. The spatial path consisted of satellite and/or aircraft data, data correlation analyzer, scanner IFOV, and random noise model. The output of the spatial path was fed into the analytic classification and accuracy predictor. The spectral path consisted of laboratory and/or field spectral data, EXOSYS data retrieval, optimum spectral function calculation, data transformation, and statistics calculation. The output of the spectral path was fended into the stratified posterior performance estimator.

Landgrebe, D. A.↗
NASA NTRS1979

Description of a 2.3 kW power transformer for space applications

The principle features and special testing of a high voltage high power transformer designed and developed for space application are described. The transformer is operated in a series resonant inverter supplying beam power to a 30 cm mercury ion thruster. Electrical requirements include operation of 2.3 kW continuous power output, primary currents to 35 amps rms, and frequencies up to 20 kHz. High efficiency was obtained through detailed considerations of the tradeoffs available in core materials, wire selection, coil configurations and thermal control. A number of novel heat removal techniques are discussed which control the winding temperature using only the available conductive cooling.

Hansen, I.↗
NASA NTRS1979

Description and charging results from the RSPM

Representative satellite materials, to be flown on STP-78-2 in 1979 on the SSPM instruments, were included as part of the AFGL Rocket payload flown from White Sands Missile Range on January 21, 1978. Potentials as high as + 1100 volts on the conductor and + or - 400 volts on the insulator were recorded by the RSPM near the minimum in the electron density vs altitude profile. In addition to the charging potentials measured during ion gun operation, sample charging currents also were recorded with time resolutions near 30 milliseconds. These results demonstrate the validity of the experiment concept of the SSPM on SCATHA.

Mizera, P. F.↗
NASA NTRS1979

Description of photovoltaic village power systems in the United States and Africa

Photovoltaic power systems in remote villages in the United States and Africa are described. These projects were undertaken to demonstrate that existing photovoltaic system technology is capable of providing electrical power for basic domestic services for the millions of small, remote communities in both developed and developing countries. One system is located in the Papago Indian Village of Schuchuli in southwest Arizona (U. S.) and became operational 16 December 1978. The other system is located in Tangaye, a rural village in Upper Volta, Africa. It became operational 1 March 1979. The Schuchuli system has a 3.5 kW (peak) solar array which provides electric power for village water pumping, a refrigerator for each family, lights in the village buildings, and a community washing machine and sewing machine. The 1.8 kW (peak) Tangaye system provides power for community water pumping, flour milling and lights in the milling building. These are both stand-alone systems (i.e., no back-up power source) which are being operated and maintained by local personnel. Both systems are instrumented. Systems operations are being monitored by NASA to measure design adequacy and to refine designs for future systems.

Ratajczak, A. F.↗
NASA NTRS1979

Description of the TC 125 aboard the Mercury simulator

Two distinct phases of the TC.125 aboard the Mercury Simulator were described to pilots at a meeting in 1979. A three hour "hand on" phase, during which the pilot learns to use the system, and second; a two hour evaluation phase, during which the pilot analyzes the TC.125 and pratices making typical approaches are presented.

Source record↗
NASA NTRS1979

Description of the VTOL Approach and Landing Technology (VALT) CH-47 research system

The Langley Research Center modified a CH-47B helicopter to provide a general-purpose variable-stability capability for the VTOL approach and landing technology (VALT) program. The functional aspects and capabilities of the overall system are described. Automatic decelerating approach data are presented to illustrate the performance of the overall system.

Kelly, J. R.↗
NASA NTRS1979

HEAO-C Observatory Description

The spacecraft subsystems, scientific instrumentation, and the mission operations concept of the HEAO-C program are presented as an aid to HEAO guest observers. Scientific participants such as Principal Investigators and Co-investigators are presented.

Dailey, C.↗
NASA NTRS1979

Variational description of the positive column with two-stem ionization

The ionization balance in diffusion dominated discharges which depends on both one and two step ionization processes is considered. The Spenke diffusion equation (D sq delta n + neutrino n + sq kn =0) describing such conditions is solved by the Rayleigh-Ritz variational method. Simple analytic approximations to the density profile, and the similarity relation between neutrino,k,D and the discharge dimensions, are derived for planar and cylindrical geometry, and compared with exact computations for certain limiting cases.

Crawford, F. W.↗
NASA NTRS1979

Power Extension Package (PEP) system definition extension, orbital service module systems analysis study. Volume 12: PEP data item descriptions

Contractor information requirements necessary to support the power extension package project of the space shuttle program are specified for the following categories of data: project management; configuration management; systems engineering and test; manufacturing; reliability, quality assurance and safety; logistics; training; and operations.

Source record↗
NASA NTRS1979

Phase 1 of the First Small Power System Experiment (engineering Experiment No. 1). Volume 3: Experimental System Descriptions

The design and development of a modular solar thermal power system for application in the 1 to 10 MWe range is described. The system consists of five subsystems: the collector, power conversion, energy transport, energy storage, and the plant control subsystem. The collector subsystem consists of concentrator, receiver, and tower assemblies. The energy transport subsystem uses a mixture of salts with a low melting temperature to transport thermal energy. A steam generator drives a steam Rankine cycle turbine which drives an electrical generator to produce electricity. Thermal and stress analysis tests are performed on each subsystem in order to determine the operational reliability, the minimum risk of failure, and the maintenance and repair characteristics.

Holl, R. J.↗
NASA NTRS1979

Lightning Detection and Ranging system LDAR system description and performance objectives

The instruments used at the six remote stations to measure both the time-of-arrival of the envelope of the pulsed 60 MHz to 80 MHz portion of the RF signal emitted by lightning, and the electric field waveforms are described as well as the two methods of transmitting the signal to the central station. Other topics discussed include data processing, recording, and reduction techniques and the software used for the 2100S, 2114, and 2116 computers.

Poehler, H. A.↗
NASA NTRS1978

The CLASSY clustering algorithm: Description, evaluation, and comparison with the iterative self-organizing clustering system (ISOCLS)

A clustering method, CLASSY, was developed, which alternates maximum likelihood iteration with a procedure for splitting, combining, and eliminating the resulting statistics. The method maximizes the fit of a mixture of normal distributions to the observed first through fourth central moments of the data and produces an estimate of the proportions, means, and covariances in this mixture. The mathematical model which is the basic for CLASSY and the actual operation of the algorithm is described. Data comparing the performances of CLASSY and ISOCLS on simulated and actual LACIE data are presented.

Lennington, R. K.↗
NASA NTRS1978

Solar thermal power systems point-focusing distributed receiver /PFDR/ technology - A project description

The goal of the Project is to support the industrial development of PFDR technology that will provide favorable life-cycle costs per unit of electrical or thermal energy produced. The technology will be made available in the early 1980s for applications project experiments. PFDR systems utilize concentrator dishes to furnish energy to their own individual receivers and power conversion subsystems. Initial effort is with steam Rankine and gas Brayton cycles. Periodic assessments will be made to confirm or change the cycles initially selected. Subsystems will be designed, fabricated and tested together in modules as appropriate. This paper describes PFDR systems briefly, outlines the project goals and organization, discusses the plans and current status of the project, and lists the benefits of PFDR technology concepts.

Lucas, J. W.↗
NASA NTRS1978

Description of a computer simulation of an orbital SAR system

A computer simulation of an orbital SAR system has been developed in order to predict SAR performance for a wide variety of system and environmental parameters. The objectives of the simulation are: (1) to assess the effect of various antenna patterns on the SAR image, (2) to assess the effect of various SAR parameters on the system's ability to detect small differences in the radar cross section of adjacent homogeneous areas, and (3) to assess the effect of mapping geometry on SAR image quality. The simulation is implemented as seven programs: (1) simulation control, (2) terrain model, (3) slant range computation, (4) production of IPQ video, (5) motion compensation, (6) Doppler processor, and (7) postprocessor and display.

Crow, G. L.↗
NASA NTRS1979

Two-dimensional, time-dependent MHD description of interplanetary disturbances Simulation of high speed solar wind interactions

A two-dimensional, time-dependent nonlinear MHD model is used to simulate the general features of multiply-interacting, transient solar wind flows. The major advantage of the two-dimensional model over the one-dimensional one is the proper consideration of azimuthal gradients. In addition, the new model can provide contour maps for disturbed plasma properties in the equatorial plane, thereby enabling one to perform essential tests of the physical assumptions through direct comparison with space probe data.

Wu, S. T.↗