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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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
NASA NTRS1984

A 406 MHz geostationary satellite SARSAT experiment

A 406 MHz SARSAT experiment using the GOES system to demonstrate the utility of integrating a near-instantaneous distress alerting capability achievable by the geostationary satellites with the location capability of the low altitude, near-polar orbiting satellite system is described. Tests include the evaluation of technical performance of a variety of maritime, aviation, and land-based SARSAT beacons under operational environment conditions as well as a demonstration of system effectiveness in pseudo real distress incident situations. The technical performance tests parallel the CCIR coordinated trials program conducted at L-band frequencies using the INMARSAT satellites. Tests, including schedules, are outlined.

Friedman, M. L.↗
NASA NTRS1992

Finding The Laminar-To-Turbulent Transition

Technical memorandum evaluates four techniques for determining location laminar flow about airfoil changes to turbulent flow. Studied in flight experiments on F-14 variable-sweep-wing aircraft. First technique involved measurements by hot-film anemometer sensors. Second, measurements by boundary-layer rakes, each array of pressure probes. Third, measurements taken by pitot tubes arrayed on airfoil, flush with surface, and fourth, test airfoil surface coated with pressure-sensitive liquid crystals, to make pressure pattern of flow visible.

Anderson, Bianca T.↗
NASA NTRS1991

Design concepts for integrating the IMKA technology with CLIPS

The author shares his experiences in evaluating the technical alternatives for integrating the Initiative for Managing Knowledge Assets (IMKA) frame-based knowledge acquisition system with the C language Integrated Production System (CLIPS). Integrating the IMKA technology with CLIPS allows application knowledge to be encoded naturally, using both frames and rules, and allows the knowledge stored in frames to be reasoned about using rules. An overview is given in viewgraph form of the features of the IMKA technology. The challenges of integrating the IMKA technology with CLIPS, three integration models, and the circumstances under which each is appropriate are discussed.

Scarola, David↗
NASA NTRS2002

CRM Assessment: Determining the Generalization of Rater Calibration Training. Summary of Research Report: Gold Standards Training

The extent to which pilot instructors are trained to assess crew resource management (CRM) skills accurately during Line-Oriented Flight Training (LOFT) and Line Operational Evaluation (LOE) scenarios is critical. Pilot instructors must make accurate performance ratings to ensure that proper feedback is provided to flight crews and appropriate decisions are made regarding certification to fly the line. Furthermore, the Federal Aviation Administration's (FAA) Advanced Qualification Program (AQP) requires that instructors be trained explicitly to evaluate both technical and CRM performance (i.e., rater training) and also requires that proficiency and standardization of instructors be verified periodically. To address the critical need for effective pilot instructor training, the American Institutes for Research (AIR) reviewed the relevant research on rater training and, based on "best practices" from this research, developed a new strategy for training pilot instructors to assess crew performance. In addition, we explored new statistical techniques for assessing the effectiveness of pilot instructor training. The results of our research are briefly summarized below. This summary is followed by abstracts of articles and book chapters published under this grant.

Baker, David P.↗
NASA NTRS2002

NASA Langley and NLR Research of Distributed Air/Ground Traffic Management

Distributed Air/Ground Traffic Management (DAG-TM) is a concept of future air traffic operations that proposes to distribute information, decision-making authority, and responsibility among flight crews, the air traffic service provider, and aeronautical operational control organizations. This paper provides an overview and status of DAG-TM research at NASA Langley Research Center and the National Aerospace Laboratory of The Netherlands. Specific objectives of the research are to evaluate the technical and operational feasibility of the autonomous airborne component of DAG-TM, which is founded on the operational paradigm of free flight. The paper includes an overview of research approaches, the airborne technologies under development, and a summary of experimental investigations and findings to date. Although research is not yet complete, these findings indicate that free flight is feasible and will significantly enhance system capacity and safety. While free flight cannot alone resolve the complex issues faced by those modernizing the global airspace, it should be considered an essential part of a comprehensive air traffic management modernization activity.

Ballin, Mark G.↗
NASA NTRS2007

Progress Toward the Stars: An Overview of Ares I First Stage Elements

This viewgraph presentation reviews the progress made in the development of the Ares The information includes an overview of the Ares Launch Vehicles, progress toward the Preliminary Design Review (PDR), progress on design, development, test, and evaluation and technical progress in the development of the Ares I First Stage subsystem.

Williams, Thomas J.↗
NASA NTRS2005

Improved Emergency Egress Lighting System for the ISS

Emergency lights provide illumination in corridors, stairwells, ramps, escalators, aisles, and exit passageways during power failures. Safety and visibility are critical during a power outage. If emergency lights fail to operate properly, the building occupants can become disoriented. Four documents in a collection discuss different topics relating to a proposed improved emergency egress lighting system (EELS) for the International Space Station (ISS). While the present EELS is designed around rows of green-light-emitting diodes, the proposed system contains strips of electroluminescent tape using different colors for each egress path. The proposed EELS can be powered by the same battery currently used by the present EELS, but would require an inverter because electroluminescent devices require AC. Electroluminescent devices also require significantly less current and, depending on the color, would emit 3 to 8 times the light of the present EELS. In addition, they could operate for up to 75 hours (versus .20 minutes for the present system). The first document contains a one-page summary of the proposal and an evaluation of technical merit. The second document summarizes the motivation for, and the design of, the proposed EELS. The third document addresses relevant aspects of the measurement of spectral sensitivity and the psychophysics of perception of light. The fourth document presents additional background information and technical specifications for the electroluminescent tapes.

Eaton, Leslie L.↗
NASA NTRS2014

Public-Private Collaborations with Earth-Space Benefits

The NASA Human Health and Performance Center (NHHPC) was established in October 2010 to promote collaborative problem solving and project development to advance human health and performance innovations benefiting life in space and on Earth. The NHHPC, which now boasts over 150 corporate, government, academic and non-profit members, has convened four successful workshops and engaged in multiple collaborative projects. The virtual center facilitates member engagement through a variety of vehicles, including annual in-person workshops, webcasts, quarterly electronic newsletters, web postings, and the new system for partner engagement. NHHPC workshops serve to bring member organizations together to share best practices, discuss common goals, and facilitate development of the collaborative projects. The most recent NHHPC workshop was conducted in November 2013 on the topic of "Accelerating Innovation: New Organizational Business Models," and focused on various collaborative approaches successfully used by organizations to achieve their goals. Past workshops have addressed smart media and health applications, connecting through collaboration, microbiology innovations, and strategies and best practices in open innovation. A fifth workshop in Houston, Texas, planned for September 18, 2014, will feature "Innovation Through Co-Development: Engaging Partners". One area of great interest to NASA is mobile health applications, including mobile laboratory analytics, health monitoring, and close loop sensing, all of which also offer ground-based health applications for remote and underserved areas. Another project being coordinated by NASA and the Health and Environmental Sciences Institute is the pursuit of one to several novel strategies to increase medication stability that would enable health care in remote terrestrial settings as well as during space flight. NASA has also funded work with corporate NHHPC partner GE, seeking to develop ultrasound methodologies that will enable NASA to further understand the eye changes related to long-duration space flight. The adaptation of ultrasound to this type of eye examination could also expand the use of ultrasound in health care on the Earth in settings where MRIs are not available. To further engage NHHPC members and facilitate partnership development for NASA, the NHHPC created and deployed an engagement system in 2014 that facilitates identification and evaluation of technical needs and opportunities among all NHHPC members.

Davis, Jeffrey R.↗
NASA NTRS2014

Alternative, Green Processes for the Precision Cleaning of Aerospace Hardware

Precision cleaning is necessary to ensure the proper functioning of aerospace hardware, particularly those systems that come in contact with liquid oxygen or hypergolic fuels. Components that have not been cleaned to the appropriate levels may experience problems ranging from impaired performance to catastrophic failure. Traditionally, this has been achieved using various halogenated solvents. However, as information on the toxicological and/or environmental impacts of each came to light, they were subsequently regulated out of use. The solvent currently used in Kennedy Space Center (KSC) precision cleaning operations is Vertrel MCA. Environmental sampling at KSC indicates that continued use of this or similar solvents may lead to high remediation costs that must be borne by the Program for years to come. In response to this problem, the Green Solvents Project seeks to develop state-of-the-art, green technologies designed to meet KSCs precision cleaning needs.Initially, 23 solvents were identified as potential replacements for the current Vertrel MCA-based process. Highly halogenated solvents were deliberately omitted since historical precedents indicate that as the long-term consequences of these solvents become known, they will eventually be regulated out of practical use, often with significant financial burdens for the user. Three solvent-less cleaning processes (plasma, supercritical carbon dioxide, and carbon dioxide snow) were also chosen since they produce essentially no waste stream. Next, experimental and analytical procedures were developed to compare the relative effectiveness of these solvents and technologies to the current KSC standard of Vertrel MCA. Individually numbered Swagelok fittings were used to represent the hardware in the cleaning process. First, the fittings were cleaned using Vertrel MCA in order to determine their true cleaned mass. Next, the fittings were dipped into stock solutions of five commonly encountered contaminants and were weighed again showing typical contaminant deposition levels of approximately 0.00300g per part. They were then cleaned by the solvent or process being tested and then weighed a third time which allowed for the calculation of the cleaning efficiency of the test solvent or process.Based on preliminary experiments, five solvents (ethanol, isopropanol, acetone, ethyl acetate, and tert-butyl acetate) were down selected for further testing. When coupled with ultrasonic agitation, these solvents removed hydrocarbon contaminants as well as Vertrel MCA and showed improved removal of perfluorinated greases. Supercritical carbon dioxide did an excellent job dissolving each of the five contaminants but did a poor job of removing Teflon particles found in the perfluorinated greases. Plasma cleaning efficiency was found to be dependent on which supply gas was used, exposure time, and gas pressure. Under optimized conditions it was found that breathing air, energized to the plasma phase, was able to remove nearly 100% of the contamination.These findings indicate that alternative cleaning methods are indeed able to achieve precision levels of cleanliness. Currently, our team is working with a commercial cleaning company to get independent verification of our results. We are also evaluating the technical and financial aspects of scaling these processes to a size capable of supporting the future cleaning needs of KSC.

Vertrel MCA↗
NASA NTRS2019

Advanced Noise Control Fan: A 20-Year Retrospective of Contributions to Aeroacoustics Research

The Advanced Noise Control Fan (ANCF) (formerly the Active Noise Control Fan) was utilized in the design, test, and evaluation for technical risk mitigation of most of the innovative fan noise reduction technologies developed by NASA over the past 20 years (Figure 3). The ANCF is a low-speed ducted-fan testbed for measuring and understanding fan-generated aeroacoustics, duct propagation, and radiation to the far field. It is considered a low technology readiness level (TRL) testbed. The international aeroacoustics research community employed the ANCF to facilitate advancement of multiple noise reduction and measurement technologies and for code validation. From 1994 to 2016, it was located in the NASA Glenn Research Center’s Aero-Acoustic Propulsion Laboratory (AAPL). In 2016, the ANCF was transferred to the University of Notre Dame (UND) where it is expected to continue to positively impact ducted-fan aeroacoustic research. This paper summarizes the capabilities and contributions of the ANCF to the field by documenting its history.

Sutliff, Daniel L.↗
NASA NTRS2019

A 20 Year Retrospective of The Advanced Noise Control Fan - Contributions to Turbofan Noise Research

The Advanced Noise Control Fan (neé Active Noise Control Fan - ANCF) was utilized in the design, test, and evaluation for technical risk mitigation of most of the innovative fan noise reduction technologies developed by NASA over the past 20 years. The ANCF is a low-speed, ducted fan, testbed for measuring and understanding fan-generated aeroacoustics, duct propagation, and radiation to the farfield. It is considered a low Technology Readiness Level testbed. The international aeroacoustics research community employed the ANCF to facilitate advancement of multiple noise reduction and measurement technologies, and for code validation. From 1994 to 2016, it was located in the NASA Glenn Research Center’s Aero-Acoustic Propulsion Laboratory. In 2016 the ANCF was transferred to the University of Notre Dame where it is expected to continue to positively impact ducted fan aeroacoustic research and provide STEM support. This paper summarizes the capabilities and contributions of the ANCF to the field by documenting its history. Limited data is presented, focusing on a description of the configurations, goals, and objectives of representative ANCF tests. This provides an overview of the progress of aeroacosustic research as implemented on the ANCF, as well as a background for its continued usage.

Fan Noise↗
NASA NTRS2019

A 20 Year Retrospective of The Advanced Noise Control Fan - Contributions to Turbofan Noise Research

The Advanced Noise Control Fan (Active Noise Control Fan - ANCF) was utilized in the design, test, and evaluation for technical risk mitigation of most of the innovative fan noise reduction technologies developed by NASA over the past 20 years. The ANCF is a low-speed ducted fan test bed for measuring and understanding fan-generated aeroacoustics, duct propagation, and radiation to the farfield. It is considered a low Technology Readiness Level testbed. The international aeroacoustics research community employed the ANCF to facilitate advancement of multiple noise reduction and measurement technologies, and for code validation. From 1994 to 2016, it was located in the NASA Glenn Research Center's Applied Aero Propulsion Laboratory. In 2016 the ANCF was transferred to the University of Notre Dame where it is expected to continue to positively impact ducted fan aeroacoustic research. This paper summarizes the capabilities and contributions of the ANCF to the field by documenting its history.

Duct Noise↗
NASA NTRS2020

NASA Engineering and Safety Center Technical Bulletin No. 20-07: Evaluating and Mitigating Liner Strain Spikes in COPV's

Unexpected cracking and leaking in bonded composite overwrapped pressure vessel (COPV) liners occurring in recent test programs have been attributed to liner strain spikes observed through measurement and predicted by analysis. Diminished load transfer between the liner and composite overwrap can lead to localized excessive liner yielding in the dome section. This diminished constraint can occur due to yielding of the adhesive or a manufacturing unbond defect. COPVs should be assessed for susceptibility to this new failure mode.

Evaluating↗
NASA NTRS2021

Trash Compaction and Processing System Trash Models and Evolved Gas Analysis of Trash Components

As part of the NASA Next Space Technologies for Exploration Partnerships (NextSTEP) Trash Compaction and Processing System (TCPS) program, the Generation 2 (Gen 2) Heat Melt Compactor (HMC) tests a variety of trash models (nominal, high liquid, and high cloth) in order to evaluate the technical risk associated with processing spacecraft trash. The trash components used in the trash models not only impacts the final solid trash disk quality, but also the water and gas effluent compositions. In order to better design an auxiliary system to treat the effluent streams, both the input trash components and the effluent must be characterized. Evolved gas analysis (EGA) methods are used to characterize the input trash components. The EGA results will be used to determine various HMC operational parameters, as well as to determine the optimal operation for the TCPS system.

Heat Melt Compactor↗
NASA NTRS2021

NASA Engineering and Safety Center Technical Bulletin No. 21-04: Evaluating Appropriateness of LEFM Tools for COPV and Metal Pressure Vessel Damage Tolerance Life Verification

Human spaceflight composite overwrapped pressure vessels (COPVs) and metal pressure vessels can use linear elastic fracture mechanics (LEFM) analysis to demonstrate damage tolerance life per ANSI/AIAA-S-081 for COPVs and ANSI/AIAA-S-080 for metal pressure vessels. LEFM analysis assumptions require that the crack tip plastic zone is small relative to the crack size and is completely surrounded by elastically responding material. Test and analysis have shown that LEFM tools (i.e., NASGRO*) can provide unconservative crack growth predictions for cracks in COPV liners that violate LEFM assumptions. COPV and metal pressure vessel designers should evaluate and address the violation of LEFM plasticity assumptions before using LEFM analysis tools for damage tolerance life verification.

COPV↗
NASA NTRSDate not supplied

Investigation of Intelligent Resource Management for Aviation Communications

The emergence of new aerial vehicles into the airspace as part of new initiatives, such as Advanced Air Mobility (AAM), will place growing demand for spectrum resources to support airspace operations. The traditional approach of using fixed channel allocations within standard service volumes will not allow for dynamic and efficient distribution of resources based on airspace demand; consequently, a new approach to aviation spectrum management will be required to meet the anticipated needs of airspace users. The National Aeronautics and Space Administration (NASA) is investigating the application of advanced concepts to implement a novel spectrum management approach that allows for the intelligent utilization of aviation spectrum throughout the airspace while maintaining the quality of service prescribed by aeronautical standards. This technical investigation evaluates the dynamic assignment of resources for both air-ground and air-air communication links applicable to both the emerging AAM initiative as well as the existing air traffic management system. The performance of the proposed spectrum management concepts will be evaluated using a custom modeling and simulation capability that is currently under development. The implementation of these approaches is anticipated to facilitate increased spectrum utilization efficiency and enhanced airspace capacity, which will better serve the needs of future applications.

Aeronautics↗
NASA NTRSDate not supplied

Investigation of Intelligent Resource Management for Aviation Communications

The emergence of new aerial vehicles into the airspace as part of new initiatives, such as Advanced Air Mobility (AAM), will place growing demand for spectrum resources to support airspace operations. The traditional approach of using fixed channel allocations within standard service volumes will not allow for dynamic and efficient distribution of resources based on airspace demand; consequently, a new approach to aviation spectrum management will be required to meet the anticipated needs of airspace users. The National Aeronautics and Space Administration (NASA) is investigating the application of advanced concepts to implement a novel spectrum management approach that allows for the intelligent utilization of aviation spectrum throughout the airspace while maintaining the quality of service prescribed by aeronautical standards. This technical investigation evaluates the dynamic assignment of resources for both air-ground and air-air communication links applicable to both the emerging AAM initiative as well as the existing air traffic management system. The performance of the proposed spectrum management concepts will be evaluated using a custom modeling and simulation capability that is currently under development. The implementation of these approaches is anticipated to facilitate increased spectrum utilization efficiency and enhanced airspace capacity, which will better serve the needs of future applications.

Eric Knoblock↗
DOE OSTI2019

REopt: Enabling Renewable Energy, Storage, and Combined Heat and Power

Deployment of distributed energy resources including combined heat and power (CHP), photovoltaics (PV), and battery storage is growing as building and campus owners seek to reduce energy costs and increase resilience to grid outages. While deployment of a single technology is widespread, integrated systems of multiple technologies are also becoming more common to provide maximum economic and resilience benefits. To accelerate deployment, decision makers require tools to evaluate the technical and economic feasibility of these integrated systems. This paper presents a framework for optimizing the size and dispatch strategy of CHP with PV and battery storage to minimize life-cycle cost of energy. The modeling methodology is presented, with a particular focus on the linearization of cost and performance metrics required for implementation in a mixed integer linear program. A case study is used to examine the technical and economic viability of integrated CHP, PV, and battery systems, compared to CHP-only or PV+battery storage systems. In the case study we show how the integrated systems can provide increased economic and resilience benefits compared to single technologies on their own. The case study presented shows the combined CHP, PV, and battery system resulted in a 7% lower life cycle cost than CHP only, and a 22% lower life cycle cost than PV+battery storage. The life cycle emissions for CHP, PV, and battery storage resulted in a 24% reduction than CHP only and a 17% increase than PV+battery storage.

24 POWER TRANSMISSION AND DISTRIBUTION↗