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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1995

Equivalent plate modeling for conceptual design of aircraft wing structures

This paper describes an analysis method that generates conceptual-level design data for aircraft wing structures. A key requirement is that this data must be produced in a timely manner so that is can be used effectively by multidisciplinary synthesis codes for performing systems studies. Such a capability is being developed by enhancing an equivalent plate structural analysis computer code to provide a more comprehensive, robust and user-friendly analysis tool. The paper focuses on recent enhancements to the Equivalent Laminated Plate Solution (ELAPS) analysis code that significantly expands the modeling capability and improves the accuracy of results. Modeling additions include use of out-of-plane plate segments for representing winglets and advanced wing concepts such as C-wings along with a new capability for modeling the internal rib and spar structure. The accuracy of calculated results is improved by including transverse shear effects in the formulation and by using multiple sets of assumed displacement functions in the analysis. Typical results are presented to demonstrate these new features. Example configurations include a C-wing transport aircraft, a representative fighter wing and a blended-wing-body transport. These applications are intended to demonstrate and quantify the benefits of using equivalent plate modeling of wing structures during conceptual design.

Giles, Gary L.↗
NASA NTRS2002

Teaching, Learning, and Planetary Exploration

This is the final report of a program that examined the fundamentals of education associated with space activities, promoted educational policy development in appropriate forums, and developed pathfinder products and services to demonstrate the utility of advanced communication technologies for space-based education. Our focus was on space astrophysics and planetary exploration, with a special emphasis on the themes of the Origins Program, with which the Principal Investigator (PI) had been involved from the outset. Teaching, Learning, and Planetary Exploration was also the core funding of the Space Telescope Science Institute's (ST ScI) Special Studies Office (SSO), and as such had provided basic support for such important NASA studies as the fix for Hubble Space Telescope (HST) spherical aberration, scientific conception of the HST Advanced Camera, specification of the Next-Generation Space Telescope (NGST), and the strategic plan for the second decade of the HST science program.

Brown, Robert A.↗
NASA NTRS2001

Fundamentals of Digital Engineering: Designing for Reliability

The concept of designing for reliability will be introduced along with a brief overview of reliability, redundancy and traditional methods of fault tolerance is presented, as applied to current logic devices. The fundamentals of advanced circuit design and analysis techniques will be the primary focus. The introduction will cover the definitions of key device parameters and how analysis is used to prove circuit correctness. Basic design techniques such as synchronous vs asynchronous design, metastable state resolution time/arbiter design, and finite state machine structure/implementation will be reviewed. Advanced topics will be explored such as skew-tolerant circuit design, the use of triple-modular redundancy and circuit hazards, device transients and preventative circuit design, lock-up states in finite state machines generated by logic synthesizers, device transient characteristics, radiation mitigation techniques. worst-case analysis, the use of timing analyzer and simulators, and others. Case studies and lessons learned from spaceflight designs will be given as examples

Katz, R.↗
NASA NTRS2011

Asset Analysis and Operational Concepts for Separation Assurance Flight Testing at Dryden Flight Research Center

A preliminary survey of existing separation assurance and collision avoidance advancements, technologies, and efforts has been conducted in order to develop a concept of operations for flight testing autonomous separation assurance at Dryden Flight Research Center. This effort was part of the Unmanned Aerial Systems in the National Airspace System project. The survey focused primarily on separation assurance projects validated through flight testing (including lessons learned), however current forays into the field were also examined. Comparisons between current Dryden flight and range assets were conducted using House of Quality matrices in order to allow project management to make determinations regarding asset utilization for future flight tests. This was conducted in order to establish a body of knowledge of the current collision avoidance landscape, and thus focus Dryden s efforts more effectively towards the providing of assets and test ranges for future flight testing within this research field.

Costa, Guillermo J.↗
NASA NTRS2017

Cost-Driven Design of a Large Scale X-Plane

A conceptual design process focused on the development of a low-cost, large scale X-plane was developed as part of an internal research and development effort. One of the concepts considered for this process was the double-bubble configuration recently developed as an advanced single-aisle class commercial transport similar in size to a Boeing 737-800 or Airbus A320. The study objective was to reduce the contractor cost from contract award to first test flight to less than $100 million, and having the first flight within three years of contract award. Methods and strategies for reduced cost are discussed.

Welstead, Jason R.↗
NASA NTRS2006

Pattern-Based Genetic Algorithm for Airborne Conflict Resolution

NASA has developed the Autonomous Operations Planner (AOP) airborne decision support tool to explore advanced air traffic control concepts that include delegating separation authority to aircraft. A key element of the AOP is its strategic conflict resolution (CR) algorithm, which must resolve conflicts while maintaining conformance with traffic flow management constraints. While a previous CR algorithm, which focused on broader flight plan optimization objectives as a part of conflict resolution, had successfully been developed, new research has identified the need for resolution routes the users find more acceptable (i.e., simpler and more intuitive). A new CR algorithm is presented that uses a combination of pattern-based maneuvers and a genetic algorithm to achieve these new objectives. Several lateral and vertical maneuver patterns are defined and the application of the genetic algorithm explained. A new approach to defining a conflicted fitness function using estimates of the local conflict region around a conflicted trajectory is also presented. Preliminary performance characteristics of the implemented algorithm are provided.

Vivona, Robert A.↗
NASA NTRS2009

Advancement of Optical Component Control for an Imaging Fabry-Perot Interferometer

Risk mitigation activities associated with a prototype imaging Fabry-Perot Interferometer (FPI) system are continuing at the NASA Langley Research Center. The system concept and technology center about enabling and improving future space-based atmospheric composition missions, with a current focus on observing tropospheric ozone around 9.6 micron, while having applicability toward measurement in different spectral regions and other applications. Recent activities have focused on improving an optical element control subsystem to enable precise and accurate positioning and control of etalon plates; this is needed to provide high system spectral fidelity critical for enabling the required ability to spectrally-resolve atmospheric line structure. The latest results pertaining to methodology enhancements, system implementation, and laboratory characterization testing will be reported

Larar, Allen M.↗
NASA NTRSDate not supplied

Performance Risk Model (PRisM) Proof-of-Concept: An Operational Decision Support Tool to Predict Crew Performance in Space from Available Performance Tests

The Crew Health and Performance-Probabilistic Risk Assessment (CHP-PRA) team at NASA Glenn Research Center has developed a range of tools to evaluate astronaut health during spaceflight and to optimize the medical set required for missions. Among these, the Performance Risk Model (PRisM) represents a novel advancement, extending CHP-PRA’s focus beyond medical systems into the domain of human performance. Such tool could be pivotal in optimizing astronaut capabilities during space travel, thereby enhancing overall mission success. PRisM leverages data from well-established performance assessments conducted during previous crewed space missions and Earth analogs to strategically predict outcomes for planned tasks, even when direct performance testing has not been conducted for those specific tasks. To evaluate performance, PRisM references the various metrics outlined in NASA-STD-3001 and employs a methodology to integrate different performance scales. This framework analyzes the contribution of various human system task categories (HSTCs) to task execution and compares these contributions to the HSTCs’ involvement in other known tests. The model further employs a Monte Carlo simulation to sample performance scores from their distribution in operationally relevant tests such as those in Mulavara et al. (2018) and, by leveraging similarities in HSTC involvement, transfers this knowledge to actual mission tasks, such as those outlined in the "Human Exploration of Mars: Preliminary List of Crew Tasks”. The current PRisM proof-of-concept includes analyses of the impact of exercise and specific medications on astronauts’ performance, with provisions to incorporate additional countermeasures as data becomes available. Furthermore, the tool is customizable to include any system necessary to fully encompass the domain of human systems and can be adapted to evaluate performance for any spaceflight activities as requested by operational stakeholders. PRisM has the potential to assist the Human Research Program in exploring the capabilities trade space for optimized crew performance.

performance modeling↗
NASA NTRSDate not supplied

Enhanced Flight Dynamics Models with Aerodynamic Interference for Real-Time Simulation of VTOL Concept Vehicles

In an effort to establish common models to support the Advanced Air Mobility (AAM) community, NASA has designed a fleet of VTOL configuration reference models. Advanced Rotorcraft Technologies (ART) in cooperation with the NASA Ames Aeromechanics branch has developed FLIGHTLAB simulation models for several of these AAM VTOL concept vehicles. These simulation models are real-time capable while maintaining accurate flight dynamic characteristics with enhanced interference simulation by extracting important modeling parameters from Viscous Vortex Particle Method (VVPM). The focus of this paper is threefold. First, it introduces the simulation models developed and describes their modeling characteristics important to control and flight dynamics simulation. Second, the method for deriving the interference coefficients between model components such as rotors and wings is outlined. Implementation of the method for the lift+cruise and tiltwing models are discussed in detail. Third, the accuracy of the interference enhancement is assessed, with emphasis placed on the impacts to trim and flight dynamic characteristics. The interference enhancement method is further used to evaluate configuration design decisions by quantifying performance aspects of interference. This research effort culminated in simulation models for the AAM VTOL concept vehicles, with proper interference and real-time capability.

Flight Dynamics↗
DOE OSTI2023

Valuation of pollination services from habitat management: a case study of utility scale solar energy facilities in the United States

Creating and maintaining pollinator habitats following the ecological infrastructure concept in degraded or unutilized land, such as solar energy facilities, is a practical way to synergistically advance the food, energy, and ecology nexus. Given the large land-use requirements for solar farming—the fastest growing renewable energy technology–considerable attention has been focused on strategies to maximize multiple ecosystem services. In this study, we coupled the principles of agronomy and ecology with economics and integrated national-scale data on crops, pollinators, and solar facilities to identify locations for creating pollinator habitats and estimating the economic value of pollination from the habitats. We examined opportunities for pollination services from pollinator-friendly utility-scale solar facilities adjacent to 42 million hectares of pollination-dependent crops in the conterminous United States at high resolution of 1 ha. We used the net income method to estimate the potential economic value of creating habitat in the land adjacent to solar facilities in the eight states with the greatest number of solar installations. Creating pollinator habitats at the 217 utility-scale solar facilities in these states could support adjacent 80,000 hectares of high pollinator dependent crops, which could potentially generate a pollination value of $\$$120 to $\$$264 million USD. The location-specific information and high-resolution maps generated for the United States demonstrate integration of grey and green infrastructure to support the food, energy, and environment nexus.

14 SOLAR ENERGY↗
NASA NTRS1980

NASA's program in communication satellites

It is noted that NASA is currently proceeding with a revitalized R&D program aimed at the development and demonstration of advanced communication satellite system concepts and the related enabling technologies. The paper reviews the important elements of this program thrust, the approach NASA is taking to assure proper involvement of both the system supplier industry and the service supplier industry and the specific technology focus in the near term. Finally, highlights of the current NASA and industry activities related to opening up the 30/20 GHz frequency band for both commercial and military use are presented.

Sivo, J. N.↗
NASA NTRS1989

Advanced Manned Launch Systems

Advanced Manned Launch Systems (AMLS) studies underway at the NASA Langley Research Center are part of a broader effort examining options for the next U.S. manned space transportation system. AMLS study phases have focused on investigating mission needs and identifying technologies and technology levels, concepts, systems, operational requirements, and life-cycle costs. For near-term technologies and an operations-oriented approach, two-stage vertical-takeoff rocket vehicles with significant levels of reusability are shown to be cost-effective for moderate to high flight rates. All-hydrogen fuel vehicles are also preferred over methane boosted systems from both operational and cost considerations.

Talay, Theodore A.↗
NASA NTRS2004

Mechanical Components Branch Test Facilities and Capabilities

The Mechanical Components Branch at NASA Glenn Research Center formulates, conducts, and manages research focused on propulsion systems for both present and advanced aeronautical and space vehicles. The branch is comprised of research teams that perform basic research in three areas: mechanical drives, aerospace seals, and space mechanisms. Each team has unique facilities for testing aerospace hardware and concepts. This report presents an overview of the Mechanical Components Branch test facilities.

Oswald, Fred B.↗
NASA NTRS2015

Heliopause Electrostatic Rapid Transit System (HERTS)

A recent six month investigation focused on: "Determining the benefits of propelling a scientific spacecraft by an 'Electric Sail' propulsion system to the edge of our solar system (the Heliopause), a distance of 100 to 120 AU, in ten years or less" has recently been completed by the Advance Concepts Office at NASA's MSFC. The concept investigated has been named the Heliopause Electrostatic Rapid Transit System (HERTS) by the MSFC team. The HERTS is a revolutionary propellant-less propulsion concept that is ideal for deep space missions to the Outer Planets, Heliopause, and beyond. It is unique in that it uses momentum exchange from naturally occurring solar wind protons to propel a spacecraft within the heliosphere. The propulsion system consists of an array of electrically positively-biased wires that extend outward 20 km from a rotating (one revolution per hour) spacecraft. It was determined that the HERTS system can accelerate a spacecraft to velocities as much as two to three times that possible by any realistic extrapolation of current state-of-the-art propulsion technologies- including solar electric and solar sail propulsion systems. The data produced show that a scientific spacecraft could reach distances of 100AU in less than 10 years. Moreover, it can be reasonably expected that this system could be developed within a decade and provide meaningful Heliophysics Science and Outer Planetary Science returns in the 2025-2035 timeframe.

Wiegmann, Bruce M.↗
NASA NTRS2015

Gas House Autonomous System Monitoring

Gas House Autonomous System Monitoring (GHASM) will employ Integrated System Health Monitoring (ISHM) of cryogenic fluids in the High Pressure Gas Facility at Stennis Space Center. The preliminary focus of development incorporates the passive monitoring and eventual commanding of the Nitrogen System. ISHM offers generic system awareness, adept at using concepts rather than specific error cases. As an enabler for autonomy, ISHM provides capabilities inclusive of anomaly detection, diagnosis, and abnormality prediction. Advancing ISHM and Autonomous Operation functional capabilities enhances quality of data, optimizes safety, improves cost effectiveness, and has direct benefits to a wide spectrum of aerospace applications.

Miller, Luke↗
NASA NTRSDate not supplied

National Campaign Partner Demonstration Team Annual Review April 2023

- NASA developed the Advanced Air Mobility Project (AAM) and the National Campaign (NC) series to identify and address challenges ahead for advanced air mobility concepts. - NC seeks to challenge industry as follows; - Execute progressively more difficult ecosystem-wide system-level safety and integration scenarios - Demonstrate practical and scalable system concepts - Build a knowledge base for development of requirements and standards - There are currently three focus areas within the NASA AAM NC Portfolio - Vehicle Development and Operations: test and inform capabilities that are critical enablers for AAM such as electric aircraft propulsion and increasing levels of automation - Airspace Design and Operations: develop and validate an operational concept to integrate and manage AAM traffic safely and efficiently - Community Integration: understand and address critical barriers to community integration, such as public acceptance (noise, security, privacy, etc.), supporting infrastructure, and local regulation

Eric N Becker↗
NASA NTRS2011

Initial Assessment of Open Rotor Propulsion Applied to an Advanced Single-Aisle Aircraft

Application of high speed, advanced turboprops, or propfans, to subsonic transport aircraft received significant attention and research in the 1970s and 1980s when fuel efficiency was the driving focus of aeronautical research. Recent volatility in fuel prices and concern for aviation s environmental impact have renewed interest in unducted, open rotor propulsion, and revived research by NASA and a number of engine manufacturers. Unfortunately, in the two decades that have passed since open rotor concepts were thoroughly investigated, NASA has lost experience and expertise in this technology area. This paper describes initial efforts to re-establish NASA s capability to assess aircraft designs with open rotor propulsion. Specifically, methodologies for aircraft-level sizing, performance analysis, and system-level noise analysis are described. Propulsion modeling techniques have been described in a previous paper. Initial results from application of these methods to an advanced single-aisle aircraft using open rotor engines based on historical blade designs are presented. These results indicate open rotor engines have the potential to provide large reductions in fuel consumption and emissions. Initial noise analysis indicates that current noise regulations can be met with old blade designs and modern, noiseoptimized blade designs are expected to result in even lower noise levels. Although an initial capability has been established and initial results obtained, additional development work is necessary to make NASA s open rotor system analysis capability on par with existing turbofan analysis capabilities.

Guynn, Mark D.↗
NASA NTRSDate not supplied

Advancing Electric Propulsion Aircraft Evaluation for Urban Air Mobility: Insights from NASA Ames

This presentation delves into a recent evaluation conducted at NASA-Ames on the Vertical Motion Simulator, focusing on the handling qualities of Distributed Electric Propulsion VTOL (eVTOL) aircraft, specifically tailored for Urban Air Mobility (UAM) applications. The presentation will focus on the recent effort to adapt and refine use of the Aeronautical Design Standard -33 (ADS-33) rotorcraft handling qualities developed by the U.S. Army and NASA to meet the diverse needs of civilian (eVTOL) concept evaluation. A brief discussion of the author’s personal test pilot insights in the early development of military Fly-By-Wire evaluation methods will also be provided. The emergence of innovative eVTOL designs with unique lift capabilities and flight control systems, present both opportunities and challenges, particularly in ensuring safety amidst technological complexity. To navigate these challenges, our investigation examined evaluation criteria designed to accommodate the varied configurations and advanced automation systems inherent in modern eVTOL aircraft. By establishing a standardized approach to evaluation, our research not only fosters innovation but also upholds safety standards in the dynamic landscape of urban air mobility. Through this endeavor, we help to facilitate the seamless integration of novel aircraft capabilities into new operations, contributing to a new era of safe and efficient aerial transportation.

eVTOL↗