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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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Variables taken into account in glider flight strategy decisions are modeled. These include height of clouds, distance between thermals, time of day, water ballast, present altitude, weather changes, lift organization, and distance to goal, as well as the strength of the next thermal. Results of the Monte Carlo atmospheric model are discussed.
The deformation of flow in the boundary layer and the local separation of a laminar layer (laminar bubbles) from various airfoils were investigated. These phenomena were classified and their influence is discussed. Various aerodynamic characteristics are discussed and the principles for prescribing pressure distribution to attain a high value of c sub z max with a possibly low drag coefficient are described.
The lack of a simple rate coefficient expression to describe the pressure and temperature dependence hampers chemical modeling of flame systems. Recently developed simplified models to describe unimolecular processes include the calculation of rate constants for thermal unimolecular reactions and recombinations at the low pressure limit, at the high pressure limit and in the intermediate fall-off region. Comparison between two different applications of Troe's simplified model and a comparison between the simplified model and the classic RRKM theory are described.
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The historical progression of efficiency improvements, cost reductions, and performance improvements in modules and photovoltaic systems are described. The potential for future improvements in photovoltaic device efficiencies and cost reductions continues as device concepts, designs, processes, and automated production capabilities mature. Additional step-function improvements can be made as today's simpler devices are replaced by more sophisticated devices.
International cooperative efforts undertaken by NASA are evaluated and consideration is given to the proposed space station. The Shuttle RMS and Spacelab were constructed through efforts of Canadian and European companies and the ESA. Landsat, with its widely dispersed technology and data, has encouraged international access to its capabilities and start-up of follow-on programs in other countries. Space station planning is proceeding with a view to worldwide utilization of space and to the commitment and resources other nations are willing to place in the station. It is conceded that administrative difficulties will arise if the space station is a completely international effort guided by NASA. Additionally, concern will be present for technology leaks, national security implications on the space station, and reasonably fulfilling the benefits expected by those who become partners in the construction and operation of the station.
Rotorcraft noise includes turbofan engine noise components, as well as noise from the main and tail rotors that is conditioned by the aircraft's various operational modes. Both of the rotors generate loading noise and broadband noise. Another noise contributor is blade/vortex interaction noise, which results when shed vortices are encountered by a following blade, releasing impulsive acoustic energy. Attention is presently given to the experimental and developmental initiatives to be made by a NASA/industry five-year program that began in 1983. Aeroacoustic data acquired from experiments conducted in NASA facilities can be used in the development of empirical noise prediction methods, in the improvement of existing noise prediction methodology, in the evaluation of proposed reduced noise designs, and in the establishment of useful scaling relationships for selected noise-generating mechanisms.
NASA's Microgravity Science and Applications Program is directed toward research in the science and technology of processing materials under conditions of low gravity. The objective is to make a detailed examination of the constraints imposed by gravitational forces on Earth. The program is expected to lead ultimately to the development of new materials and processes in Earth-based commercial applications, adding to this nation's technological base. An important resource that U.S. researchers have readily available to them is the new Microgravity Materials Science Laboratory (MMSL) at NASA Lewis Research Center in Cleveland. A typical scenario for a microgravity materials experiment at Lewis would begin by establishing 1-g baseline data in the MMSL and then proceeding, if it is indicated, to a drop tower or to simulated microgravity conditions in a research aircraft to qualify the project for space flight. A major component of Lewis microgravity materials research work involves the study of metal and alloy solidification fundamentals.
The pricing policies of different data-base services offering Predicast data bases are examined from a user perspective. The services carrying these data bases are listed; the problems introduced by varying exchange rates and seemingly idiosyncratic price structures are discussed; and numerous specific examples are given.
The stress history of the moon is discussed, taking into consideration the effects of thermal contraction and differentiation. The amount of expansion caused by extracting basalt from undifferentiated lunar material is estimated taking account of the uncertainty in the knowledge of the appropriate compositions, and the resulting estimate of the expansion is used to compare the relative importance of the thermal and differentiation effects in the moon's volumetric history. The results of calculations show that differentiation is likely to be of major importance and, thus, thermal expansion is not the sole possible contributor to evolutionary changes in the lunar radius.
The possibility of using Federally funded scientific and technical information (STI) to increase U.S. industrial innovation and productivity is discussed. The history of Federally funded research and development in the fields of agriculture and aviation is reviewed as an example of successful government-sponsored research. Issues related to the production and utilization of information are considered and Federal STI policy is outlined. Issues related to the transfer of knowledge between government agencies and industry are examined and a model depicting the transfer of STI in aerospace research and development is presented. Also, consideration is given to the problem of open communication versus restricted access to STI.
The possibility of using federally funded scientific and technical information (STI) to increase U.S. industrial innovation and productivity is discussed. The history of federally funded research and development in the fields of agriculture and aviation is reviewed as an example of successful government-sponsored research. Issues related to the production and utilization of information are considered and federal STI policy is outlined. Issues related to the transfer of knowledge between government agencies and industry are examined and a model depicting the transfer of STI in aerospace research and development is presented. Also, consideration is given to the problem of open communication versus restricted access to STI.
During Fall and Winter quarters, Georgia Tech's School of Mechanical Engineering students designed machines and devices related to Lunar Base construction tasks. These include joint projects with Textile Engineering students. Topics studied included lunar environment simulator via drop tower technology, lunar rated fasteners, lunar habitat shelter, design of a lunar surface trenching machine, lunar support system, lunar worksite illumination (daytime), lunar regolith bagging system, sunlight diffusing tent for lunar worksite, service apparatus for lunar launch vehicles, lunar communication/power cables and teleoperated deployment machine, lunar regolith bag collection and emplacement device, soil stabilization mat for lunar launch/landing site, lunar rated fastening systems for robotic implementation, lunar surface cable/conduit and automated deployment system, lunar regolith bagging system, and lunar rated fasteners and fastening systems. A special topics team of five Spring quarter students designed and constructed a remotely controlled crane implement for the SKITTER model.
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Foreign competitors are challenging the world leadership of the U.S. aerospace industry, and increasingly tight budgets everywhere make international cooperation in aerospace science necessary. The NASA STI Program has as part of its mission to support NASA R&D, and to that end has developed a knowledge base of aerospace-related information known as the NASA Aerospace Database. The NASA STI Program is already involved in international cooperation with NATO/AGARD/TIP, CENDI, ICSU/ICSTI, and the U.S. Japan Committee on STI. With the new more open political climate, the perceived dearth of foreign information in the NASA Aerospace Database, and the development of the ESA database and DELURA, the German databases, the NASA STI Program is responding by sponsoring workshops on foreign acquisitions and by increasing its cooperation with international partners and with other U.S. agencies. The STI Program looks to the future of improved database access through networking and a GUI; new media; optical disk, video, and full text; and a Technology Focus Group that will keep the NASA STI Program current with technology.
This session of discussions reports on two sides of the technology transfer issue. The speakers are representatives of the aluminum industry (Alcoa Aluminum) and the National Aeronautics and Space Administration, Office of Commercial Programs. They discuss what technology transfer means, what NASA does for industry, and how information is disseminated.
The ab initio results presently obtained for the potential energy surface of competing associative and reactive ion-molecule processes of the reactants H2 and C3H(+) show that the linear ion is able to directly access the deep potential well of the propargyl ion H2CCCH(+). Using the minimum energy potential pathway and properties of the stationary point structures determined via the ab initio methods, calculation results are obtained for both the association-rate coefficient for C3H3(+) production as a function of density, and the branching ratio between the propargyl and cyclic structures of the ion.
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