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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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Core/Combustor-Noise Update

Future propulsion systems for ultra-efficient commercial air vehicles are projected to be of increasingly higher bypass ratios resulting from larger fans combined with much smaller cores, with ultra-clean burning fuel-flexible combustors. Unless effective noise-reduction strategies are developed, combustor noise is likely to become a prominent contributor to overall airport community noise in the future. This presentation gives a brief overview of the NASA outlook on pertinent issues and far-term research needs as well as current and planned research in the core/combustor-noise area. The research described herein is aligned with the NASA Ultra-Efficient Commercial Transport strategic thrust and is supported by the NASA Advanced Air Vehicle Program, Advanced Air Transport Technology Project, under the Aircraft Noise Reduction Subproject. The overarching goal of the Advanced Air Transport Technology (AATT) Project is to explore and develop technologies and concepts to revolutionize the energy efficiency and environmental compatibility of fixed wing transport aircrafts. These technological solutions are critical in reducing the impact of aviation on the environment even as this industry and the corresponding global transportation system continue to grow.

Hultgren, Lennart S.↗
NASA NTRS1997

2 kWe Solar Dynamic Ground Test Demonstration Project: Design Report - Volume 2

Critical Design Reviews (CDR's) were held on the Solar Dynamic Ground Test Demonstrator (SDGTD). This CDR summary report will provide the following information for each of the system components and the system integration: (1) A bibliography of design/design review documentation; (2) A summary of the major discussion issues from issues from each design review; (3) A definition of the component and system detail designs along with the bottom line from the supporting analysis; (4) Status and key results from pertinent development activities on-going in the CDR time period; (5) A brief description of planned testing; and (6) A discussion of issues stiff open at the completion of CDR. Appendix 1 to this report contains a listing and status (as of 28 June 1993) of all the action items generated during all SDGTD CDRs. The reader should remember that the SDGTD program is being conducted in an open communication forum, and program participants are encouraged to ask questions or request information. Team members are allowed and encouraged to participate in the reviews on an equal basis. No request for information, as long as it is within the work scope, is refused, so many action items are generated.

Alexander, Dennis↗
NASA NTRS1989

Theory of wide-angle photometry from standard stars

Wide angle celestial structures, such as bright comet tails and nearby galaxies and clusters of galaxies, rely on photographic methods for quantified morphology and photometry, primarily because electronic devices with comparable resolution and sky coverage are beyond current technological capability. The problem of the photometry of extended structures and of how this problem may be overcome through calibration by photometric standard stars is examined. The perfect properties of the ideal field of view are stated in the guise of a radiometric paraxial approximation, in the hope that fields of view of actual telescopes will conform. Fundamental radiometric concepts are worked through before the issue of atmospheric attenuation is addressed. The independence of observed atmospheric extinction and surface brightness leads off the quest for formal solutions to the problem of surface photometry. Methods and problems of solution are discussed. The spectre is confronted in the spirit of standard stars and shown to be chimerical in that light, provided certain rituals are adopted. After a brief discussion of Baker-Sampson polynomials and the vexing issue of saturation, a pursuit is made of actual numbers to be expected in real cases. While the numbers crunched are gathered ex nihilo, they demonstrate the feasibility of Newton's method in the solution of this overdetermined, nonlinear, least square, multiparametric, photometric problem.

Usher, Peter D.↗
NASA NTRS1982

NASA educational briefs

In response to a large public demand for information, the Educational Services Branch of NASA has undertaken a series of publications designed for use by teachers, titled 'Educational Briefs for the Classroom', which has resulted in six to eight issues each year for the last three years. Typical of the topics to which the series is dedicated have been space suits, manned spaceflight mission summaries, solar cells, planetary encounter data, orbits, and rocketry. The planning committee for Educational Briefs is aided in its selection of topics by the many letters received by NASA. Following the Voyager Saturn flybys, NASA received more than 175,000 letters from both children and adults.

Vogt, G. L.↗
DOE OSTI1991

Recommendations for Establishing Local Rural Electrification Programs Using Photovoltaic Systems [Recomendaciones Para la Implantacidn de Programas Locales de Electrificacidn Rural con Sistemas Fotovoltaicos]

Photovoltaic (PV) technology is becoming one the best options for supplying electricity to rural communities far from electrical networks and which have a small and disperse demand for electricity. As the cost of the technology goes down and its development advances, opportunities for applying it continue to grow. As a result, in the near future we will probably see an increase in massive application programs of this technology in rural Mexico. This document presents some of the most relevant problems needing immediate solution to increase the possibility of success in establishing photovoltaic programs for rural electrification in Mexico. These problems are influenced by economic, technological, engineering, infrastructural, social and political issues. The paper presents the requirements for an industrial center based on PV technology, the accessibility of replacement parts and maintenance service, development of financial solutions, training of the users and introducing norms and technical regulations. The document summarizes the issue of rural electrification in Mexico, emphasizing the low population density in these areas. A brief description is given of photovoltaics showing different configurations that can be utilized for supplying electricity to the rural areas. The issues involved and recommendations for introducing PV systems to the rural area are described.

14 SOLAR ENERGY↗
NASA NTRS2008

"Built-In" Action/Issues Tracking and Post-Ops Analysis Tool for Realtime Console Operations

Marshall Space Flight Center's (MSFC) Payload Operations Integration Center (POIC) for the International Space Station (ISS) uses a number of formal databases to manage and track flight plan changes, onboard and ground equipment anomalies, and other events. However, individual console positions encounter many action items and/or occurrences that don't fit neatly into the databases, and while console logs are comprehensive, manual or automated searches do not always yield consistent results. The Payload Communications Manager (PAYCOM) team, whose members speak directly with the ISS onboard crew with respect to NASA payload operations, has found a creative way to reformat a mandatory Daily Report to organize action items, standing reminders, significant events, and other comments. While the report keeps others appraised of PAYCOMs activities and issues of the moment, the format makes it easy to capture very brief summaries of the items in a "Roll Off Matrix", including start and stop dates, resolution, and possible applicability to future ops. The matrix provides accountability for all action items, gives direct insight into the issues surrounding various payloads and methods of dealing with them, yields indirect information on PAYCOM priorities and processes, and provides a roadmap that makes it easier to get back to extensive details if needed. This paper describes how the ISS PAYCOM Daily Report and Roll Off Matrix are organized, used, and inter-related to each other and the PAYCOM operations log. While the application is for a manned vehicle, the concepts could apply in a wide spectrum of operational settings.

Scott, David W.↗
NASA NTRS2002

Lessons learned from Shuttle/Mir: psychosocial countermeasures

BACKGROUND: During future long-duration space missions, countermeasures need to be developed to deal with psychosocial issues that might impact negatively on crewmember performance and well-being. METHODS: In our recently completed NASA-funded study of 5 U.S. astronauts, 8 Russian cosmonauts, and 42 U.S. and 16 Russian mission control personnel who participated in the Shuttle/Mir program, we evaluated a number of important psychosocial issues such as group tension, cohesion, leadership role, and the displacement of negative emotions from crewmembers to people in mission control and from mission control personnel to management. RESULTS: Based on our findings, which are reviewed, a number of psychosocial countermeasures are suggested to help ameliorate the negative impact of potential psychosocial problems during future manned space missions. CONCLUSIONS: Crewmembers should be selected not only to rule out psychopathology but also to select-in for group compatibility and facility in a common language. Training should include briefings and team building related to a number of psychosocial issues and should involve both crewmembers and mission control personnel. During the mission, both experts on the ground and the crewmembers themselves should be alert to potential interpersonal problems, including the displacement of negative emotions from the crew to the ground. Supportive activities should consist of both individual and interpersonal strategies, including an awareness of changing leisure time needs. Finally, attention should be given to postmission readjustment and to supporting the families on Earth.

Non-NASA Center↗
NASA NTRS1990

The ISES: A non-intrusive medium for in-space experiments in on-board information extraction

The Information Science Experiment System (ISES) represents a new approach in applying advanced systems technology and techniques to on-board information extraction in the space environment. Basically, what is proposed is a 'black box' attached to the spacecraft data bus or local area network. To the spacecraft the 'black box' appears to be just another payload requiring power, heat rejection, interfaces, adding weight, and requiring time on the data management and communication system. In reality, the 'black box' is a programmable computational resource which eavesdrops on the data network, taking and producing selectable, real-time science data back on the network. This paper will present a brief overview of the ISES Concept and will discuss issues related to applying the ISES to the polar platform and Space Station Freedom. Critical to the operation of ISES is the viability of a payload-like interface to the spacecraft data bus or local area network. Study results that address this question will be reviewed vis-a-vis the solar platform and the core space station. Also, initial results of processing science and other requirements for onboard, real-time information extraction will be presented with particular emphasis on the polar platform. Opportunities for a broader range of applications on the core space station will also be discussed.

Murray, Nicholas D.↗
NASA NTRSDate not supplied

Status of the GSICS VIS/NIR DCC Calibration Efforts

This year's goals for the GSICS VIS/NIR group is to finalize the VIS/NIR demonstration product requirements and to process the product for public dissemination provided on the GSICS web page. The GSICS VIS/NIR group members have been working on a unified calibration approach among various agencies. Two calibration methods have been chosen for the visible bands, deep convective clouds (DCC) and lunar invariant targets. To come to consensus across the agencies, each step of the DCC process will be outlined. Brief discussions are to follow to determine any outstanding issues. The presentation will review the DCC calibration process implemented by the CERES calibration team. CERES has already implemented the DCC method across 18 geostationary satellites. The various agencies have taken the framework and optimized the method for their particular geostationary satellite. Several new improvements will be discussed, such as deseasonalization of the DCC reflectances, impact of the bidirectional model, and update frequency.

David Doelling↗
DOE OSTI2023

Summary of Bats and Land-Based Wind Energy Development in the United States and Canada

In light of future deployment scenarios, there is increasing concern over the potential population-level impacts of wind energy development on bats. Resolving the impact of bat interactions with wind turbines is a priority issue for wind energy and wildlife stakeholders. This research brief summarizes our current understanding of the patterns of activity and fatality of bats at wind energy facilities across the United States and Canada, existing strategies to reduce fatality, and research questions that need to be answered to sustain bat populations while producing renewable energy.

acoustic ceterrents↗
NASA NTRS2011

The Continual Intercomparison of Radiation Codes: Results from Phase I

The computer codes that calculate the energy budget of solar and thermal radiation in Global Climate Models (GCMs), our most advanced tools for predicting climate change, have to be computationally efficient in order to not impose undue computational burden to climate simulations. By using approximations to gain execution speed, these codes sacrifice accuracy compared to more accurate, but also much slower, alternatives. International efforts to evaluate the approximate schemes have taken place in the past, but they have suffered from the drawback that the accurate standards were not validated themselves for performance. The manuscript summarizes the main results of the first phase of an effort called "Continual Intercomparison of Radiation Codes" (CIRC) where the cases chosen to evaluate the approximate models are based on observations and where we have ensured that the accurate models perform well when compared to solar and thermal radiation measurements. The effort is endorsed by international organizations such as the GEWEX Radiation Panel and the International Radiation Commission and has a dedicated website (i.e., http://circ.gsfc.nasa.gov) where interested scientists can freely download data and obtain more information about the effort's modus operandi and objectives. In a paper published in the March 2010 issue of the Bulletin of the American Meteorological Society only a brief overview of CIRC was provided with some sample results. In this paper the analysis of submissions of 11 solar and 13 thermal infrared codes relative to accurate reference calculations obtained by so-called "line-by-line" radiation codes is much more detailed. We demonstrate that, while performance of the approximate codes continues to improve, significant issues still remain to be addressed for satisfactory performance within GCMs. We hope that by identifying and quantifying shortcomings, the paper will help establish performance standards to objectively assess radiation code quality, and will guide the development of future phases of CIRC

Oreopoulos, Lazaros↗
DOE OSTI2023

Identification and Evaluation for Fueling of NRIC DOME Reactors Report

The National Reactor Innovation Center (NRIC) has designed a testbed for advanced microreactor experiments that enables and encourages technology developers to bring advanced designs closer to commercial availability. The test bed, Demonstration of Microreactor Experiments (DOME), will be used to facilitate much of the operation experimentation process of the each advanced microreactor including fueling and operational power experiments. This report identifies and evaluates the options for initial fueling the microreactors in DOME. This report also discusses the optional locations that were considered for the initial fueling of microreactor; namely the Transient Reactor Test (TREAT) reactor building, and an unspecified temporary location. But various logistical and construction issues essentially eliminated these other options from further consideration. A brief discussion in this report outlines potential equipment and protocol associated with fueling in DOME.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
NASA NTRS1987

Parallel processing in finite element structural analysis

A brief review is made of the fundamental concepts and basic issues of parallel processing. Discussion focuses on parallel numerical algorithms, performance evaluation of machines and algorithms, and parallelism in finite element computations. A computational strategy is proposed for maximizing the degree of parallelism at different levels of the finite element analysis process including: 1) formulation level (through the use of mixed finite element models); 2) analysis level (through additive decomposition of the different arrays in the governing equations into the contributions to a symmetrized response plus correction terms); 3) numerical algorithm level (through the use of operator splitting techniques and application of iterative processes); and 4) implementation level (through the effective combination of vectorization, multitasking and microtasking, whenever available).

Noor, Ahmed K.↗
NASA NTRS1988

High-energy particles very near the sun

NASA's long range plans include a Solar Probe (Star Probe) mission in which a spacecraft is placed in an eccentric orbit with perihelion at four solar radii. As part of the study effort for this mission, a Solar Probe Environment Workshop was sponsored by JPL. The report of this committee was issued in September 1978 as JPL Publication 78-64. A brief abstract of this document is given. There are considerable uncertainties in the models of solar energetic particle release and transport. The committee addressed this problem by using different modelling techniques when possible to provide a cross-check on the estimates. These models were used to extrapolate observation at 1 AU to the vicinity of the Sun. Additionally, the occurrence of a flare of a given magnitude must be estimated on a statistical basis. Therefore, it is possible to state a likelihood that the fluxes and fluences will be less than a certain magnitude, but in the event of an extremely large solar flare (occurrence of perhaps once a decade, e.g., August 4, 1972) it is likely that the hazard would be insurmountable. A brief first look indicates that the near-solar particle environment is not a worse hazard than Jupiter.

Goldstein, B. E.↗
NASA NTRS1989

Measuring cloud properties from space - A review

A brief review of observations of clouds using satellites highlights open issues and directions for future studies. The key one is improved treatment of the effects of small-scale spatial inhomogeneity in remote sensing data analyses and in the treatment of radiation in climate models, though studies and observations of the spectral dependence of cloud-radiation interactions are also limited. Significant progress in understanding the role of clouds in climate, especially regarding cloud-radiation budget relationships, is expected in the next several years because of an unprecedent suite of global and regional observation and analysis programs.

Rossow, William B.↗
NASA NTRS1991

Rover nuclear rocket engine program: Overview of rover engine tests

The results of nuclear rocket development activities from the inception of the ROVER program in 1955 through the termination of activities on January 5, 1973 are summarized. This report discusses the nuclear reactor test configurations (non cold flow) along with the nuclear furnace demonstrated during this time frame. Included in the report are brief descriptions of the propulsion systems, test objectives, accomplishments, technical issues, and relevant test results for the various reactor tests. Additionally, this document is specifically aimed at reporting performance data and their relationship to fuel element development with little or no emphasis on other (important) items.

Finseth, J. L.↗
NASA NTRS1993

Perceptual factors that influence use of computer enhanced visual displays

This document is the final report for the NASA/Langley contract entitled 'Perceptual Factors that Influence Use of Computer Enhanced Visual Displays.' The document consists of two parts. The first part contains a discussion of the problem to which the grant was addressed, a brief discussion of work performed under the grant, and several issues suggested for follow-on work. The second part, presented as Appendix I, contains the annual report produced by Dr. Ann Fulop, the Postdoctoral Research Associate who worked on-site in this project. The main focus of this project was to investigate perceptual factors that might affect a pilot's ability to use computer generated information that is projected into the same visual space that contains information about real world objects. For example, computer generated visual information can identify the type of an attacking aircraft, or its likely trajectory. Such computer generated information must not be so bright that it adversely affects a pilot's ability to perceive other potential threats in the same volume of space. Or, perceptual attributes of computer generated and real display components should not contradict each other in ways that lead to problems of accommodation and, thus, distance judgments. The purpose of the research carried out under this contract was to begin to explore the perceptual factors that contribute to effective use of these displays.

Littman, David↗
NASA NTRS1996

Spacecraft System Failures and Anomalies Attributed to the Natural Space Environment

The natural space environment is characterized by many complex and subtle phenomena hostile to spacecraft. The effects of these phenomena impact spacecraft design, development, and operations. Space systems become increasingly susceptible to the space environment as use of composite materials and smaller, faster electronics increases. This trend makes an understanding of the natural space environment essential to accomplish overall mission objectives, especially in the current climate of better/cheaper/faster. This primer provides a brief overview of the natural space environment - definition, related programmatic issues, and effects on various spacecraft subsystems. The primary focus, however, is to catalog, through representative case histories, spacecraft failures and anomalies attributed to the natural space environment. This primer is one in a series of NASA Reference Publications currently being developed by the Electromagnetics and Aerospace Environments Branch, Systems Analysis and Integration Laboratory, Marshall Space Flight Center (MSFC), National Aeronautics and Space Administration (NASA).

Bedingfield, Keith, L.↗