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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 163 records · Page 9

Optical Computing Research at NASA

Scientists at the Marshall Space Flight Center (NASA), Universities Space Research Association (USRA), the University of Alabama in Huntsville (UAH), and the Alliance for Nonlinear Optics (ANLO) are working to develop thin-film organic-based materials useful for making optical devices. These devices can use photons exclusively to transmit data, or use both photons and electrons to form electronic/optical hybrids called electrooptic devices.

Abdeldayem, H. A.↗

Rocket-Based Combined-Cycle Propulsion Technology for Access-to-Space Applications

NASA's Office of Aero-Space Technology (OAST) established three major goals, referred to as, "The Three Pillars for Success". The Advanced Space Transportation Program Office (ASTP) at the NASA's Marshall Space Flight Center (MSFC) in Huntsville, Ala. focuses on future space transportation technologies under the "Access to Space" pillar. One of the main activities over the past three years has been on advancing the hydrogen fueled rocket-based combined cycle (RBCC) technologies. The RBCC effort that was completed early this year was the initial step leading to flight demonstrations of the technology for space launch vehicle propulsion. Aerojet and Boeing-Rocketdyne designed, built and ground tested their RBCC engine concepts. In addition, ASTROX, Georgia Institute of Technology, McKinney Associates, Pennsylvania State University (PSU), and University of Alabama in Huntsville conducted supporting activities. The RBCC activity included ground testing of components (e.g., injectors, thrusters, ejectors and inlets) and integrated flowpaths. Inlet testing was performed at the Lewis Research Center's 1 x 1 wind tunnel. All direct connect and free-jet engine testing were conducted at the GASL facilities on Long Island, New York. Testing spanned the Mach range from sea level static to Mach 8. Testing of the rocket-only mode, simulating the final phase of the ascent mission profile, was also performed. The originally planned work on these contracts was completed in 1999. Follow-on activities have been initiated for both hydrogen and hydrocarbon fueled RBCC concepts. Studies to better understand system level issues with the integration of RBCC propulsion with earth-to-orbit vehicles have also been conducted. This paper describes the status, progress and future plans of the RBCC activities funded by NASA/MSFC with a major focus on the benefits of utilizing air-breathing combined-cycle propulsion in access-to-space applications.

Hueter, Uwe↗

On the Origin and Evolution of Stellar Chromospheres, Coronae and Winds

This grant was awarded by NASA to The University of Alabama in Huntsville (UAH) to construct state-of-the-art, theoretical, two-component, chromospheric models for single stars of different spectral types and different evolutionary status. In our proposal, we suggested to use these models to predict the level of the "basal flux", the observed range of variation of chromospheric activity for a given spectral type, and the decrease of this activity with stellar age. In addition, for red giants and supergiants, we also proposed to construct self-consistent, purely theoretical wind models, and used these models to investigate the origin of "dividing lines" in the H-R diagram. In the following, we describe our completed work. We have accomplished the first main goal of our proposal by constructing first purely theoretical, time-dependent and two-component models of stellar chromospheres.1 The models require specifying only three basic stellar parameters, namely, the effective temperature, gravity and rotation rate, and they take into account non-magnetic and magnetic regions in stellar chromospheres. The non-magnetic regions are heated by acoustic waves generated by the turbulent convection in the stellar subphotospheric layers. The magnetic regions are identified with magnetic flux tubes uniformly distributed over the entire stellar surface and they are heated by longitudinal tube waves generated by turbulent motions in the subphotospheric and photospheric layers. The coverage of stellar surface by magnetic regions (the so-called filling factor) is estimated for a given rotation rate from an observational relationship. The constructed models are time-dependent and are based on the energy balance between the amount of mechanical energy supplied by waves and radiative losses in strong Ca II and Mg II emission lines. To calculate the amount of wave energy in the non-magnetic regions, we have used the Lighthill-Stein theory for sound generation.

Musielak, Z. E.↗

Space Solar Power Exploratory Research and Technology (SERT) Technical Interchange Meeting 2 (SERT TIM 2)

The University of Alabama in Huntsville's (UAH) Propulsion Research Center hosted the Space Solar Power Exploratory Research & Technology (SERT) Technical Interchange Meeting TIM) 2 in Huntsville, Alabama December 7-10. 1999 with 126 people in attendance. The SERT program includes both competitively procured activities. which are being implemented through a portfolio of focused R&D investments--with the maximum leveraging of existing resources inside and outside NASA. and guided by these system studies. Axel Roth. Director of the Flight Projects Directorate NASA MSFC, welcomed the SERT TIM 2 participants and challenged them to develop the necessary technologies and demonstrations that will lead to Space Solar Power (SSP) International implementation. Joe Howell, NASA MSFC, reiterated the SERT TIM 2 objectives: 1) Refining and modeling systems approaches for the utilization of SSP concepts and technologies, ranging, from the near-term e.g. for space science, exploration and commercial space applications to the far-term (e. g. SSP for terrestrial markets), including systems concepts, technology, infrastructure (i.g., transportation), and economics. 2) Conducting technology research, development and demonstration activities to produce "proof- of-concept" validation of critical SSP elements for both the nearer and farther-term applications. 3) Initiating partnerships Nationality and Internationally that could be expanded, as appropriate, to pursue later SSP technology and applications (e.g., space science. colonization, etc.). Day one began with the NASA Centers presenting their SERT activities summary since SERT TIM 1 and wound up with a presentation by Masahiro Mori, NASDA titled "NASDA In-house Study for SSP". Demonstration for the Near-Term. Day two began with the SERT Systems Studies and Analysis reports resulting from NRA 8-23 followed by presentations of SERT Technology Demonstrations reports resulting from NRA 8-23. Day two closed with John Mankins presentation on "Technology Roadmapping" and the delivery of the charge to the Work Breakout Sessions. Day three began with the eleven Work Breakout Session which was the major function of this TIM 2 and day three ended with reports by the Chairs of the eleven Work Breakdown Sessions. Day four began with the six Integrated Product Team OPT) meetings and ended with closing plenary panel sessions.

Howell, Joe↗

Consortium for Materials Development in Space

During FY99 the Consortium for Materials Development in Space (CMDS) was reorganized around the following guidelines: industry driven, product focus, an industry led advisory council, focus on University of Alabama in Huntsville (UAH) core competencies, linkage to regional investment firms to assist commercialization and to take advantage of space flights. The organizational structure of the CMDS changed considerably during the year. The decision was made to reduce the organization to a Director and an Administrative Assistant. The various research projects, including the employees, were transferred to the appropriate UAH research center or college. In addition, an advisory council was established to provide direction and guidance to the CMDS to ensure a strong commercial focus. The council will (i) review CMDS commercial development plans and provide feedback, (ii) perform an annual evaluation of the Center's progress and present the results of this review to the UAH Vice President for Research, (iii) serve as an avenue of communication between the CMDS and its commercial partners, and (iv) serve as an ambassador and advocate for the CMDS.

Source record↗

Modeling Specular Exchange Between Concentric Cylinders in a Radiative Shielded Furnace

The objective of this research is to develop and validate mathematical models to characterize the thermal performance of a radiative shielded furnace, the University of Alabama in Huntsville (UAH) Isothermal Diffusion Oven. The mathematical models are validated against experimental data obtained from testing the breadboard oven in a terrestrial laboratory environment. It is anticipated that the validation will produce math models capable of predicting the thermal performance of the furnace over a wide range of operating conditions, including those for which no experimental data is available. Of particular interest is the furnace core temperature versus heater power parametric and the transient thermal response of the furnace. Application to a microgravity environment is not considered, although it is conjectured that the removal of any gravity dependent terms from the math models developed for the terrestrial application should yield adequate results in a microgravity environment. The UAH Isothermal Diffusion Oven is designed to provide a thermal environment that is conducive to measuring the diffusion of high temperature liquid metals. In addition to achieving the temperatures required to melt a sample placed within the furnace, reducing or eliminating convective motions within the melt is an important design consideration [1]. Both of these influences are reflected in the design of the furnace. Reducing unwanted heat losses from the furnace is achieved through the use of low conductivity materials and reflective shielding. As evidenced by the highly conductive copper core used to house the sample within the furnace, convective motions can be greatly suppressed by providing an essentially uniform thermal environment. An oven of this design could ultimately be utilized in a microgravity environment, presumably as a experiment payload. Such an application precipitates other design requirements that limit the resources available to the furnace such as power, mass, volume, and possibly even time. Through the experimental and numerical results obtained, the power requirements and thermal response time of the breadboard furnace are quantified.

Schunk, Richard Gregory↗

Evaluation of Incremental Releases of ECS User Interfaces and the Development of HDF/HDF-EOS Tutorials

During the reporting period, the PI has continued to serve on numerous review panels, task forces, and committees with the goal of providing input and guidance for the Earth Observing System Data and Information System (EOSDIS) program at NASA Headquarters and NASA Goddard Space Flight Center (GSFC). In addition, the PI has worked together with personnel at Simpson Weather Associates (SWA) to help create an on-line HDF/HDF-EOS tutorial for beginning and non-expert users of both the Hierarchical Data Format (HDF) and HDF-EOS data format and software libraries. Finally, the PI has worked together with personnel at SWA and the Information Technology and Systems Center (ITSC) at the University of Alabama in Huntsville (UAH) on a feasibility study regarding the use of data mining software to ascertain features from the gridded output from numerical meteorological forecast models. A summary of these activities is provided.

Emmitt, G. D.↗

The Athena Raman Spectrometer

Raman spectroscopy provides a powerful tool for in situ mineralogy, petrology, and detection of water and carbon. The Athena Raman spectrometer is a microbeam instrument intended for close-up analyses of targets (rock or soils) selected by the Athena Pancam and Mini-TES. It will take 100 Raman spectra along a linear traverse of approximately one centimeter (point-counting procedure) in one to four hours during the Mars' night. From these spectra, the following information about the target will extracted: (1) the identities of major, minor, and trace mineral phases, organic species (e.g., PAH or kerogen-like polymers), reduced inorganic carbon, and water-bearing phases; (2) chemical features (e.g. Mg/Fe ratio) of major minerals; and (3) rock textural features (e.g., mineral clusters, amygdular filling and veins). Part of the Athena payload, the miniaturized Raman spectrometer has been under development in a highly interactive collaboration of a science team at Washington University and the University of Alabama at Birmingham, and an engineering team at the Jet Propulsion Laboratory. The development has completed the brassboard stage and has produced the design for the engineering model.

Wang, Alian↗

Adjustable Focus Optical Correction Lens (AFOCL)

This report describes a metrology plan that was developed for the characterization of PLZT-based devices, such as the Adjustable Focus Optical Correction Lens (AFOCL) in support of and as part of the deliverables for NASA contract NAS8-00118. The areas to be investigated include intensiometric effects (those that limit or alter the intensity of the light transmitted through the optic); interferometric effects (the phase change induced through the optic); and polarimetric effects (evaluating the differential lag between two polarization states propagating through the optic). These distinct phenomena are often coupled together in real applications consequently, there is a need to develop different standardized testing apparatus to: (1) isolate one effect from another; (2) gather information for understanding the physical effects; (3) anchor wavefront corrector modeling efforts; (4) develop the ability to decouple different effects; (5) demonstrate the suitability of PLZT technology to perform wavefront correction. The Center for Applied Optics (CAO) at the University of Alabama in Huntsville (UAH) is skilled in the characterization of transmission wavefront shaping devices using traditional interferometers available within the CAO Optical Metrology Laboratory and their Advanced Polarization Test Facility. Besides the imaging and interferometers available, the polarimetry facility has at its disposal, a Mueller Matrix Imaging Polarimeter (MMIP) which is well suited to the characterization of SLMs, polarizers, and thin film coatings within the visible and near-IR spectrums. In addition, the phase-shifting interferometry facilities at NASA-MSFC and the unique interferometers they processes are some of the most advanced available and may be of value especially for performing real-time optical performance evaluation of AFOCL test components.

Peters, Bruce R.↗

G-LIMIT

Dynamic modeling and controller design efforts were conducted at the University of Alabama in Huntsville (UAH) on the Glovebox Integrated Microgravity Isolation Technology (g-LIMIT), under NAG8-1598; the funded period of performance was 8/26/98 through 12/31/00. The title of the grant was 'Support of g-LIMIT for Isolation of Space Science Experiments: Dynamic Modeling and Optimal Controller Synthesis.' Design codes were developed for implementation of a steady-state H infinity controller design method using the frequency weighted plant for the MDOF g-LIMIT design case.

Hampton, R. David↗

Lightweight Lidar Telescopes for Space Applications

NASA is intent on exploiting the unique perspective of space-based remote optical instruments to observe and study large-scale environmental processes. Emphasis on smaller and more affordable missions continues to force the remote sensing instruments to find innovative ways to reduce the size, weight, and cost of the sensor package. This is a challenge because many of the proposed instruments incorporate a high quality meter-class telescope that can be a significant driver of total instrument costs. While various methods for telescope weight reduction have been achieved, many of the current approaches rely on exotic materials and specialized manufacturing techniques that limit availability or substantially increase costs. A competitive lightweight telescope technology that is especially well suited to space-based coherent Doppler wind lidar has been developed through a collaborative effort involving NASA Marshall Space Flight Center (MSFC) through the Global Hydrology and Climate Center (GHCC) and the University of Alabama in Huntsville (UAH) at the Center for Applied Optics (CAO). The new lightweight optics using metal alloy shells and surfaces (LOMASS) fabrication approach is suitable for high quality metal mirrors and meter-class telescopes. Compared to alternative materials and fabrication methods the new approach promises to reduce the areal density of a meter-class telescope to less than 15-kg/sq m; deliver a minimum VIO-RMS surface optical quality; while using commercial materials and equipment to lower procurement costs. The final optical figure and finish is put into the mirrors through conventional diamond turning and polishing techniques. This approach is especially advantageous for a coherent lidar instrument because the reduced telescope weight permits the rotation of the telescope to scan the beam without requiring heavy wedges or additional large mirrors. Ongoing investigations and preliminary results show promise for the LOMASS approach to be successful in demonstrating a novel alternative approach to fabricating lightweight mirrors with performance parameters comparable with the Space Readiness Coherent Lidar Experiment (SPARCLE). Development and process characterization is continuing with the design and fabrication of mirrors for a 25-cm telescope suitable for a lidar instrument.

Peters, Bruce R.↗

Fabrication, Metrology and Modeling of the Space-Based Lidar Telescope for SPARCLE

Over the past 7 years, NASA Marshall Space Flight Center (MSFC) through the Global Hydrology and Climate Center (GHCC) has been working; in collaboration with the University of Alabama in Huntsville (UAH) Center for Applied Optics (CAO), and others; towards demonstrating a solid state coherent Doppler lidar instrument for space-based global measurement of atmospheric winds. The Space Readiness Coherent Lidar Experiment (SPARCLE) was selected by NASA's New Millennium Program to demonstrate the feasibility and technology readiness of space-based coherent wind lidar. The CAO was responsible for the design, development, integration, and testing of the SPARCLE optical system. Operating at 2-micron wavelength, SPARCLE system performance is dominated by the optical quality of the transmitter/receiver optical system. The stringent optical performance requirements coupled with the demanding physical and environmental constraints of a space-based instrument necessitate extensive characterization of the telescope optical performance that is critical to predicting the lidar system efficiency and operation in space. Individual components have been measured prior to assembly and compared to the designed specifications. Based on the individual components, the telescope design was optimized to produce a suitable telescope. Once the telescope is completed, it will be tested and evaluated and the data shall be used to anchor computer based models of the optical system. Commercial optical modeling codes were used to evaluate the performance of the telescope under a variety of anticipated on-orbit environments and will eventually be compared to environmental tests conducted in the course of qualifying the telescope for flight. Detailed analysis using the "as built" data will help to reduce uncertainties within the lidar system model and will increase the accuracy of the lidar performance predictions.

Peters, Bruce R.↗

Anaerobic Psychrophiles from Alaska, Antarctica, and Patagonia: Implications to Possible Life on Mars and Europa

Microorganisms preserved within the permafrost, glaciers, and polar ice sheets of planet Earth provide analogs for microbial life forms that may be encountered in ice or permafrost of Mars, Europa, Callisto, Ganymede, asteroids, comets or other frozen worlds in the Cosmos. The psychrophilic and psychrotolerant microbes of the terrestrial cryosphere help establish the thermal and temporal limitations of life on Earth and provide clues to where and how we should search for evidence of life elsewhere in the Universe. For this reason, the cold-loving microorganisms are directly relevant to Astrobiology. Cryo-preserved microorganisms can remain viable (in deep anabiosis) in permafrost and ice for millions of years. Permafrost, ice wedges, pingos, glaciers, and polar ice sheets may contain intact ancient DNA, lipids, enzymes, proteins, genes, and even frozen and yet viable ancient microbiota. Some microorganisms carry out metabolic processes in water films and brine, acidic, or alkaline channels in permafrost or ice at temperatures far below 0 T. Complex microbial communities live in snow, ice-bubbles, cryoconite holes on glaciers and ancient microbial ecosystems are cryopreserved within the permafrost, glaciers, and polar caps. In the Astrobiology group of the NASA Marshall Space Flight Center and the University of Alabama at Huntsville, we have employed advanced techniques for the isolation, culture, and phylogenetic analysis of many types of microbial extremophiles. We have also used the Environmental Scanning Electron Microscope to study the morphology, ultra-microstructure and chemical composition of microorganisms in ancient permafrost and ice. We discuss several interesting and novel anaerobic microorganisms that we have isolated and cultured from the Pleistocene ice of the Fox Tunnel of Alaska, guano of the Magellanic Penguin, deep sea sediments from the vicinity of the Rainbow Hydrothermal Vent and enrichment cultures from ice of the Patriot Hills of Antarctica. The microbial extremophiles recovered from permafrost, ice, cold pools and deep sea sediments may provide information relevant to the question of how and where we should search for evidence of extant or extinct microbial life elsewhere in the Cosmos.

Hoover, Richard B.↗

Modeled Aerosol Optical Properties From Measurement-Based Mixtures of Chemical Species: Assessing the Impacts of Particle Morphology and Absorption

This report serves as the final report for the Colorado State University portion of this grant. The original grant was awarded to CSU under the direction of co-Principal Investigators Kirk Fuller and Sonia Kreidenweis. Upon Dr. Fuller's relocation to the University of Alabama - Huntsville, the major portion of the award was also relocated. The following summarizes only that work completed by Prof. Kreidenweis under her remaining award.

Kreidenweis, Sonia↗

Global Change Research Related in the Earth's Energy and Hydrologic Cycle

The mission of the Global Change Research Related to the Earth's Energy and Hydrologic Cycle is to enhance the scientific knowledge and educational benefits obtained from NASA's Earth Science Enterprise and the U.S. Global Change Research Program, University of Alabama in Huntsville (UAH). This paper presents the final technical report on this collaborative effort. Various appendices include: A) Staff Travel Activities years one through three; B) Publications and Presentations years one through three; C) Education Activities; D) Students year one through three; E) Seminars year one through three; and F) Center for Applied Optics Projects.

Berry, Linda R.↗

Anaerobic Psychrophiles from Alaska, Antarctica, and Patagonia: Implications to Possible Life on Mars and Europa

Microorganisms preserved within the permafrost, glaciers, and polar ice sheets of planet Earth provide analogs for microbial life forms that may be encountered in ice or permafrost of Mars, Europa, Callisto, Ganymede, asteroids, comets or other frozen worlds in the Cosmos. The psychrophilic and psychrotolerant microbes of the terrestrial cryosphere help establish the thermal and temporal limitations of life on Earth and provide clues to where and how we should search for evidence of life elsewhere in the Universe. For this reason, the cold-loving microorganisms are directly relevant to Astrobiology. Cryopreserved microorganisms can remain viable (in deep anabiosis) in permafrost and ice for millions of years. Permafrost, ice wedges, pingos, glaciers, and polar ice sheets may contain intact ancient DNA, lipids, enzymes, proteins, genes, and even frozen and yet viable ancient microbiota. Some microorganisms carry out metabolic processes in water films and brine, acidic, or alkaline channels in permafrost or ice at temperatures far below 0 C. Complex microbial communities live in snow, ice-bubbles, cryoconite holes on glaciers and ancient microbial ecosystems are cryopreserved within the permafrost, glaciers, and polar caps. In the Astrobiology group of the NASA Marshall Space Flight Center and the University of Alabama at Huntsville, we have employed advanced techniques for the isolation, culture, and phylogenetic analysis of many types of microbial extremophiles. We have also used the Environmental Scanning Electron Microscope to study the morphology, ultra-microstructure and chemical composition of microorganisms in ancient permafrost and ice. We discuss several interesting and novel anaerobic microorganisms that we have isolated and cultured from the Pleistocene ice of the Fox Tunnel of Alaska, guano of the Magellanic Penguin, deep-sea sediments from the vicinity of the Rainbow Hydrothermal Vent and enrichment cultures from ice of the Patriot Hills of Antarctica. The microbial extremophiles recovered from permafrost, ice, cold pools and deep-sea sediments may provide information relevant to the question of how and where we should search for evidence of extant or extinct microbial life elsewhere in the Cosmos.

Hoover, Richard B.↗

The Tenth Thermal and Fluids Analysis Workshop

The Tenth Thermal arid Fluids Analysis Workshop (TFAWS 99) was held at the Bevill Center, University of Alabama in Huntsville, Huntsville, Alabama, September 13-17, 1999. The theme for the hands-on training workshop and conference was "Tools and Techniques Contributing to Engineering Excellence". Forty-seven technical papers were presented in four sessions. The sessions were: (1) Thermal Spacecraft/Payloads, (2) Thermal Propulsion/Vehicles, (3) Interdisciplinary Paper, and (4) Fluids Paper. Forty papers were published in these proceedings. The remaining seven papers were not available in electronic format at the time of publication. In addition to the technical papers, there were (a) nine hands-on classes on thermal and flow analyses software, (b) twelve short courses, (c) thirteen product overview lectures, and (d) three keynote lectures. The workshop resulted in participation of 171 persons representing NASA Centers, Government agencies, aerospace industries, academia, software providers, and private corporations.

Majumdar, Alok↗

A Novel Method for Electroplating Ultra-High-Strength Glassy Metals

A novel method for electroplating ultra-high-strength glassy metals, nickel-phosphorous and nickel-cobalt-phosphorous, has been developed at NASA Marshall Space Flight Center, cooperatively with the University of Alabama in Huntsville. Traditionally, thin coatings of these metals are achieved via electroless deposition. Benefits of the new electrolytic process include thick, low-stress deposits, free standing shapes, lower plating temperature, low maintenance, and safer operation with substantially lower cost.

Ramsey, Brian↗