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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 181 records · Page 10

Advanced Mach 3.5 Axisymmetric Quiet Nozzle

To advance boundary-layer stability and transition research and to ultimately provide reliable predictions of transition for supersonic flight vehicles, a wind tunnel is required with very low stream disturbance levels comparable to free flight conditions. Experimental and theoretical research to develop a low-disturbance supersonic wind tunnel has achieved a breakthrough. A new concept for nozzle design is presented which promises a large increase in the length of the quiet test core. The Advanced Mach 3.5 Axisymmetric Quiet Nozzle is the first prototype built to prove the new design concept. Experimental results from this new nozzle on the extent of laminar wall boundary layers are compared with data from other nozzles and with theoretical predictions based on linear stability theory. The Reynolds numbers based on the measured length of the quiet test core for this new nozzle are in excellent agreement with the theoretical predictions. The effect of surface finish on the nozzle performance is also discussed.

Chen, Fang-Jenq↗

Conceptual design of the subscale orbital fluid transfer experiment (SOFTE)

The Subscale Orbital Fluid Transfer Experiment is a planned space experiment with the objective of obtaining video and numerical data on fluid dynamics and thermal physics pertinent to on-orbit liquid acquisition and tank filling operations, particularly with cryogens. These data have significant application to space-based transportation systems, Space Station Freedom, and space defense systems. This paper presents the rationale for the experiment and a description of its design. The experiment will mount in two Get Away Special canisters that are connected to each other by an electrical umbilical. It involves transferring Freon 113 between two transparent plexiglass tanks. Axial and tangential no-vent fills will be done over a range of flow rates. The apparatus includes a screened-channel liquid acquisition device with plexiglass channels for examining vapor breakthrough and channel refill processes. Video cameras will monitor the transfer operations.

Jones, O. S.↗

Influence of iodine on the treatment of spacecraft humidity condensate to produce potable water

Several compounds in the ersatz humidity condensate do react with iodine to form iodine-substituted organic compounds (TOI), most notably phenol, acetaldehyde, ethanol, and sodium formate. Iodination of the ersatz humidity condensate produced 3.0 to 3.5 mg/L of TOI within 24 hours. The TOI that was produced by the passage of the ersatz humidity condensate through the first iodinated resin (IR) in the adsorption system was removed by the granular activated carbon that followed. TOI detected in the final effluent was formed by the reaction of the non-adsorbable condensate compounds with the final IR in the treatment series. The activated carbon bed series in the adsorption system performed poorly in its removal of TOC. The rapid breakthrough of TOC was not surprising, as the ersatz humidity condensate contained several highly soluble organic compounds, alcohols and organic acids.

Symons, James M.↗

Characterization of metal oxide absorbents for regenerative carbon dioxide and water vapor removal for advanced portable life support systems

Characterization of the performance of a silver-oxide-based absorbent in terms of its ability to remove both gaseous CO2 and water vapor in an astronaut portable life support systems (PLSS) is discussed. Attention is focused on regeneration of the absorbent from the carbonite state of the oxide state, preconditioning of the absorbent using a humidified gas stream, and absorption breakthrough testing. Based on the results of bench-scale experiments, a test plan is carried out to further characterize the silver-oxide-based absorbent on a larger scale; it calls for examination of the absorbent in both an adiabatic packed bed and a near-isothermal cooled bed configuration. It is demonstrated that the tested absorbent can be utilized in a way that removes substantial amounts of CO2 and water vapor during an 8-hour extravehicular activity mission, and that applying the absorbent to PLSS applications can simplify the ventilation loop.

Kast, Timothy P.↗

The History Of The Kalman Filter

Paper presents historical view of adaptation of Kalman filtering techniques to aerospace applications and eventually to fields as diverse as exploration for oil and control of powerplants. Describes scientific breakthroughs and reformulations that transformed Kalman filtering techniques into fundamental tool for analyzing and solving broad class of estimation problems.

Mcgee, Leonard A.↗

Exotic power and propulsion concepts

The status of some exotic physical phenomena and unconventional spacecraft concepts that might produce breakthroughs in power and propulsion in the 21st Century are reviewed. The subjects covered include: electric, nuclear fission, nuclear fusion, antimatter, high energy density materials, metallic hydrogen, laser thermal, solar thermal, solar sail, magnetic sail, and tether propulsion.

Forward, Robert L.↗

Advanced interdisciplinary technologies

The following topics are presented in view graph form: (1) breakthrough trust (space research and technology assessment); (2) bionics (technology derivatives from biological systems); (3) biodynamics (modeling of human biomechanical performance based on anatomical data); and (4) tethered atmospheric research probes.

Anderson, John L.↗

Exploring the notion of space coupling propulsion

All existing methods of space propulsion are based on expelling a reaction mass (propellant) to induce motion. Alternatively, 'space coupling propulsion' refers to speculations about reacting with space-time itself to generate propulsive forces. Conceivably, the resulting increases in payload, range, and velocity would constitute a breakthrough in space propulsion. Such speculations are still considered science fiction for a number of reasons: (1) it appears to violate conservation of momentum; (2) no reactive media appear to exist in space; (3) no 'Grand Uniform Theories' exist to link gravity, an acceleration field, to other phenomena of nature such as electrodynamics. The rationale behind these objectives is the focus of interest. Various methods to either satisfy or explore these issues are presented along with secondary considerations. It is found that it may be useful to consider alternative conventions of science to further explore speculations of space coupling propulsion.

Millis, Marc G.↗

Spaceport operations for deep space missions

Space Station Freedom is designed with the capability to cost-effectively evolve into a transportation node which can support manned lunar and Mars missions. To extend a permanent human presence to the outer planets (moon outposts) and to nearby star systems, additional orbiting space infrastructure and great advances in propulsion system and other technologies will be required. To identify primary operations and management requirements for these deep space missions, an interstellar design concept was developed and analyzed. The assembly, test, servicing, logistics resupply, and increment management techniques anticipated for lunar and Mars missions appear to provide a pattern which can be extended in an analogous manner to deep space missions. A long range, space infrastructure development plan (encompassing deep space missions) coupled with energetic, breakthrough level propulsion research should be initiated now to assist in making the best budget and schedule decisions.

Holt, Alan C.↗

Cost-efficient manufacturing of composite structures

The Advanced Composites Technology (ACT) program is seeking research breakthroughs that will allow structures made of graphite epoxy materials to replace metals in the wings and fuselages of future aircrafts. NASA's goals are to reduce acquisition cost by 20 to 25 percent, structural weight for a resized aircraft by 40 to 50 percent, and the number of parts by half compared to current production aluminum aircraft. The innovative structural concepts, materials, and fabrication techniques emerging from the ACT program are described, and the relationship between aerospace developments and industrial, commercial, and sporting goods applications are discussed.

Freeman, W. Tom↗

Liquid jet breakup and atomization in rocket chambers under dense spray conditions

Two advanced diagnostic techniques were established and employed in this project. The first technique involves the use of a real-time x ray radiography system along with a high-speed CCD Xybion camera and an advanced digital image processor to investigate the breakup processes of the liquid core. The focus of this part of the project is to determine the inner structure of the liquid jet and via thin sheets of laser light, with the scatters light being photographed by a Xybion electronic camera synchronized to the laser pulse. This technique, which is capable of recording the breakup event occurring within 25 nano-seconds, enables us to freeze the motions of the jet and liquid droplets. The focus of this part of the project is to determine the outer structure of the liquid jet and to discover the configuration of the surface waves, the spray pattern, and the droplet size distribution in the non-dilute region. Results obtained by these two advanced diagnostic techniques will provide the much needed database for model development and accurate prediction of engine performance. The present work also represents a breakthrough in the area of advanced diagnostics of dense sprays.

Kuo, Kenneth K.↗

The High Energy Solar Physics mission (HESP): Scientific objectives and technical description

The High Energy Solar Physics mission offers the opportunity for major breakthroughs in the understanding of the fundamental energy release and particle acceleration processes at the core of the solar flare problem. The following subject areas are covered: the scientific objectives of HESP; what we can expect from the HESP observations; the high energy imaging spectrometer (HEISPEC); the HESP spacecraft; and budget and schedule.

Crannell, Carol↗

Voyager mission telecommunication firsts

The communications breakthroughs achieved during the NASA Voyager mission are discussed. The dual-spacecraft mission to Jupiter, Saturn, Uranus, Neptune, and their moons and rings was launched in 1977 and completed interplanetary phase some 12 years later with the Voyager 2 Neptune encounter in August 1989. The radio telemetry, coding, and navigation equipment of the spacecraft are examined in detail. Firsts achieved in the radio science area are also discussed. These include the fact that it was the first mission specifically designed to obtain radio-science data. It had very exacting requirements for radio system stability, both at S- and X-bands, and for frequency and timing system stability, both flight and ground.

Posner, Edward C.↗

Effect of KOH concentration on LEO cycle life of IPV nickel-hydrogen flight battery cells

A breakthrough in the low-earth-orbit (LEO) cycle life of individual pressure vessel (IPV) nickel hydrogen battery cells is reported. The cycle life of boiler plate cells containing 26 percent potassium hydroxide (KOH) electrolyte was about 40,000 LEO cycles compared to 3500 cycles for cells containing 31 percent KOH. The effect of KOH concentration on cycle life was studied. The cycle regime was a stressful accelerated LEO, which consisted of a 27.5 min charge followed by a 17.5 min charge (2 x normal rate). The depth of discharge (DOD) was 80 percent. The cell temperature was maintained at 23 C. The next step is to validate these results using flight hardware and real time LEO test. NASA Lewis has a contract with the Naval Weapons Support Center (NWSC), Crane, Indiana to validate the boiler plate test results. Six 48 A-hr Hughes recirculation design IPV nickel-hydrogen flight battery cells are being evaluated. Three of the cells contain 26 percent KOH (test cells) and three contain 31 percent KOH (control cells). They are undergoing real time LEO cycle life testing. The cycle regime is a 90-min LEO orbit consisting of a 54-min charge followed by a 36-min discharge. The depth-of-discharge is 80 percent. The cell temperature is maintained at 10 C. The cells were cycled for over 8000 cycles in the continuing test. There were no failures for the cells containing 26 percent KOH. There were two failures, however, for the cells containing 31 percent KOH.

Smithrick, John J.↗

Ada and software management in NASA: Assessment and recommendations

Recent NASA missions have required software systems that are larger, more complex, and more critical than NASA software systems of the past. The Ada programming language and the software methods and support environments associated with it are seen as potential breakthroughs in meeting NASA's software requirements. The findings of a study by the Ada and Software Management Assessment Working Group (ASMAWG) are presented. The study was chartered to perform three tasks: (1) assess the agency's ongoing and planned Ada activities; (2) assess the infrastructure (standards, policies, and internal organizations) supporting software management and the Ada activities; and (3) present an Ada implementation and use strategy appropriate for NASA over the next 5 years.

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A cost-effective intelligent robotic system with dual-arm dexterous coordination and real-time vision

Dexterous coordination of manipulators based on the use of redundant degrees of freedom, multiple sensors, and built-in robot intelligence represents a critical breakthrough in development of advanced manufacturing technology. A cost-effective approach for achieving this new generation of robotics has been made possible by the unprecedented growth of the latest microcomputer and network systems. The resulting flexible automation offers the opportunity to improve the product quality, increase the reliability of the manufacturing process, and augment the production procedures for optimizing the utilization of the robotic system. Moreover, the Advanced Robotic System (ARS) is modular in design and can be upgraded by closely following technological advancements as they occur in various fields. This approach to manufacturing automation enhances the financial justification and ensures the long-term profitability and most efficient implementation of robotic technology. The new system also addresses a broad spectrum of manufacturing demand and has the potential to address both complex jobs as well as highly labor-intensive tasks. The ARS prototype employs the decomposed optimization technique in spatial planning. This technique is implemented to the framework of the sensor-actuator network to establish the general-purpose geometric reasoning system. The development computer system is a multiple microcomputer network system, which provides the architecture for executing the modular network computing algorithms. The knowledge-based approach used in both the robot vision subsystem and the manipulation control subsystems results in the real-time image processing vision-based capability. The vision-based task environment analysis capability and the responsive motion capability are under the command of the local intelligence centers. An array of ultrasonic, proximity, and optoelectronic sensors is used for path planning. The ARS currently has 18 degrees of freedom made up by two articulated arms, one movable robot head, and two charged coupled device (CCD) cameras for producing the stereoscopic views, and articulated cylindrical-type lower body, and an optional mobile base. A functional prototype is demonstrated.

Marzwell, Neville I.↗

Applications of the Strategic Defense Initiative's compact accelerators

The Strategic Defense Initiative's (SDI) investment in particle accelerator technology for its directed energy weapons program has produced breakthroughs in the size and power of new accelerators. These accelerators, in turn, have produced spinoffs in several areas: the radio frequency quadrupole linear accelerator (RFQ linac) was recently incorporated into the design of a cancer therapy unit at the Loma Linda University Medical Center, an SDI-sponsored compact induction linear accelerator may replace Cobalt-60 radiation and hazardous ethylene-oxide as a method for sterilizing medical products, and other SDIO-funded accelerators may be used to produce the radioactive isotopes oxygen-15, nitrogen-13, carbon-11, and fluorine-18 for positron emission tomography (PET). Other applications of these accelerators include bomb detection, non-destructive inspection, decomposing toxic substances in contaminated ground water, and eliminating nuclear waste.

Montanarelli, Nick↗

OAST space technology accomplishments FY 1991

The program consists of a continuum of space research and technology activities ranging from initial research to the full scale test of prototype equipment in space. Activities include work that is performed by in-house staff at the NASA Centers, university researchers supported by NASA funded grants and contracts, and industrial aerospace organizations under contract to NASA. These diverse activities provide advances in technology breakthroughs that may revolutionalize a technical discipline or mission concept. The work is managed and coordinated by OAST through a process that integrates the best available talent and capability in NASA, industry, and universities into a National civil space research and technology program.

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