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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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Experimental computer-aided system evolution to integrate technology plans and evaluate potential resource allocations for mission-oriented technology programs
An investigation to determine the hazards potential evaluation of plastic bonded starter mix (PBSM) production processes and the application to the M18 and M7A3 grenades is reported. The investigation indicated: (1) the materials with the greatest hazards characteristics, (2) process operating stations most likely to initiate hazardous conditions, (3) the test program required to examine ignition characteristics and process hazards, and (4) the method of handling the accumulated information from testing and safety analyses.
The Apollo spacecraft pressure vessels, associated problems and resolutions, and related experience in evaluating potential problem areas are discussed. Information is provided that can be used as a guideline in the establishment of baseline criteria for the design and use of lightweight pressure vessels. One of the first practical applications of the use of fracture-mechanics technology to protect against service failures was made on Apollo pressure vessels. Recommendations are made, based on Apollo experience, that are designed to reduce the incidence of failure in pressure-vessel operation and service.
The current capabilities of LSI techniques for speed and reliability, plus the possibilities of assembling large configurations of LSI logic and storage elements, have demanded the study of multiprocessors and multiprocessing techniques, problems, and potentialities. Evaluated are three previous systems studies for a space ultrareliable modular computer multiprocessing system, and a new multiprocessing system is proposed that is flexibly configured with up to four central processors, four 1/0 processors, and 16 main memory units, plus auxiliary memory and peripheral devices. This multiprocessor system features a multilevel interrupt, qualified S/360 compatibility for ground-based generation of programs, virtual memory management of a storage hierarchy through 1/0 processors, and multiport access to multiple and shared memory units.
The design and development of a structural dynamics model of the space shuttle are discussed. The model provides for early study of structural dynamics problems, permits evaluation of the accuracy of the structural and hydroelastic analysis methods used on test vehicles, and provides for efficiently evaluating potential cost savings in structural dynamic testing techniques. The discussion is developed around the modes in which major input forces and responses occur and the significant structural details in these modes.
Existing global cloud models are improved and expanded so that they might be more effectively used in planning and evaluating potential earth-viewing space missions. A relationship is developed between the ground and satellite-derived cloud-amount frequency distributions. This relationship is used to improve internal consistency between the ground-observed unconditional statistics and the satellite-derived conditional statistics as tabulated in previous models. A statistical technique is developed which permits the scaling of the conditional statistics to time and distance separations other than those for which the data base is tabulated. A new technique to increase or decrease the representative area size of the statistical data base is developed. Both the scaling and area adjustment techniques are shown to represent significant improvements over the techniques previously employed.
Augmentor wing ducting system studies conducted on a valveless system configuration that provides cruise thrust from the augmentor nozzles have shown that most of the duct system pressure loss would occur in the strut-wing duct y-junction and the wing duct-augmentor lobe nozzles. These components were selected for development testing over a range of duct Mach numbers and pressure ratios to provide a technical basis for predicting installed wing thrust loading and for evaluating design wing loading of a particular wing aspect ratios. The flow characteristics of ducting components with relatively high pressure loss coefficients were investigated. The turbulent pressure fluctuations associated with flows at high Mach numbers were analyzed to evaluate potential duct fatigue problems.
Turbopump power gears were brought to acceptable levels of usefulness and reliability through refinements in interdependent areas of design, materials, processing, and quality control combined with extensive development testing that explored problem areas and evaluated potential solutions.
The effort undertaken during this program led to the selection of the water-superheated steam (850 psig/900 F) crescent central receiver as the preferred concept from among 11 candidate systems across the technological spectrum of the dynamic conversion of solar generated heat to electricity. The solar power plant designs were investigated in the range of plant capacities from 100 to 1000 Mw(e). The investigations considered the impacts of plant size, collector design, feed-water temperature ratio, heat rejection equipment, ground cover, and location on solar power technical and economic feasibility. For the distributed receiver systems, the optimization studies showed that plant capacities less than 100 Mw(e) may be best. Although the size of central receiver concepts was not parametrically investigated, all indications are that the optimal plant capacity for central receiver systems will be in the range from 50 to 200 Mw(e). Solar thermal power plant site selection criteria and methodology were also established and used to evaluate potentially suitable sites. The result of this effort was to identify a site south of Inyokern, California, as typically suitable for a solar thermal power plant. The criteria used in the selection process included insolation and climatological characteristics, topography, and seismic history as well as water availability.
Studies evaluating potential operational and commercial uses of space are being conducted, taking into account astronomy, astrophysics, manned bases and laboratories in earth orbit, space colonization, terrestrial communications, space processing and manufacturing, interstellar probes, planetary exploration, and the use of space for terrestrial energy supply. The present status in the exploration of the solar system is examined, giving attention to Jupiter, Venus, Mars, and Mercury. A brief outline of the development of human colonies on Mars is presented.
The financial history of the U.S. scheduled airline industry was investigated to determine the causes of the erratic profit performance of the industry and to evaluate potential economic gains from technology advances of recent years. Operational and economic factors affecting past and future profitability of the industry are discussed, although no attempt was made to examine the profitability of individual carriers. The results of the study indicate that the profit erosion of the late 1960's and early 1970's was due more to excess capacity than to inadequate fare levels, but airline problems were severely compounded by the rapid fuel price escalation in 1974 and 1975. Near-term solutions to the airline financial problems depend upon the course of action by the industry and the CAB and the general economic health of the nation. For the longer term, the only acceptable alternative to continued fare increases is a reduction in unit operating costs through technological advance. The next generation of transports is expected to incorporate technologies developed under Government sponsorship in the 1960's and 1970's with significant improvements in fuel consumption and operating costs.
Multispectral aircraft and satellite data over the West Branch of the Susquehanna River were analyzed to evaluate potential contributions of remote sensing to flood-plain surveys. Multispectral digital classifications of land cover features indicative of floodplain areas were used by interpreters to locate various floodprone area boundaries. The digital approach permitted LANDSAT results to be displayed at 1:24,000 scale and aircraft results at even larger scales. Results indicate that remote sensing techniques can delineate floodprone areas more easily in agricultural and limited development areas as opposed to areas covered by a heavy forest canopy. At this time it appears that the remote sensing data would be best used as a form of preliminary planning information or as an internal check on previous or ongoing floodplain studies. In addition, the remote sensing techniques can assist in effectively monitoring floodplain activities after a community enters into the National Flood Insurance Program.
The acquisition behavior of the PN subsystem of an automatically acquiring spacecraft receiver was studied. A symbol synchronizer subsystem was constructed and integrated into the composite simulation of the receiver. The overall performance of the receiver when subjected to anomalies such as signal fades was evaluated. Potential problems associated with PN/carrier sweep interactions were investigated.
Mathematical model of fluidized-bed process for making high-purity silicon suitable for use in solar cell production can help evaluate potential performance and economics of such processes.
To test the validity of the ARC approach to Spacelab, several missions simulating aspects of Spacelab operations have been conducted as part of the ASSESS Program. Each mission was designed to evaluate potential Shuttle/Spacelab concepts in increasing detail. For this mission, emphasis was placed on development and exercise of management techniques planned for Spacelab using management participants from NASA and ESA who have responsibilities for Spacelab 1 which will be launched in 1980.
The theoretical methodology used in developing an analysis for the response of turbine engine fan blades subjected to soft-body (bird) impacts is reported, and the computer program developed using this methodology as its basis is described. This computer program is an outgrowth of two programs that were previously developed for the purpose of studying problems of a similar nature (a 3-mode beam impact analysis and a multi-mode beam impact analysis). The present program utilizes an improved missile model that is interactively coupled with blade motion which is more consistent with actual observations. It takes into account local deformation at the impact area, blade camber effects, and the spreading of the impacted missile mass on the blade surface. In addition, it accommodates plate-type mode shapes. The analysis capability in this computer program represents a significant improvement in the development of the methodology for evaluating potential fan blade materials and designs with regard to foreign object impact resistance.
The paper investigates the astrodynamics requirements for a spacecraft which produces stereo images of the land masses of the earth for use in geoscience investigations, cartography and earth resource exploration. It describes a candidate Stereosat imaging product, presents criteria for evaluating potential image quality and usability, and assesses the impact of various spacecraft and astrodynamic factors on image quality. Several challenges are identified and discussed, namely (1) securing adequate image quality for pixel level elevation measurements, (2) determining absolute location of imaged phenomena in remote regions, (3) satisfying the long-term orbit prediction requirements, and (4) transmitting accurate orbit data along with the image data stream. Meeting these challenges will greatly enhance operational facility.
Over 10,000 square km of side-looking airborne radar (SLAR) imagery was obtained and analyzed for the siting of the first nuclear power plant in the Republic of the Philippines. The imagery was obtained using the Motorola APS/AN-94D (X-band) real aperture system as part of an overall remote sensing program to site and evaluate potential site regions. Analysis of SLAR images, in conjunction with LANDSAT, color, black and white, and thermal infrared images, provided basic information on structure, relative geochronology, stratigraphy, geomorphology, and ground water, which facilitated field operations and data synthesis.