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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 559 records · Page 31
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Technical highlights in general aviation

Improvements in performance, safety, efficiency, and emissions control in general aviation craft are reviewed. While change is slow, the U.S. industries still account for the bulk (90%) of the world's general aviation fleet. Advances in general aviation aerodynamics, structures and materials, acoustics, avionics, and propulsion are described. Supercritical airfoils, drag reduction design, stall/spin studies, crashworthiness and passenger safety, fiberglass materials, flight noise abatement, interior noise and vibration reduction, navigation systems, quieter and cleaner (reciprocating, turboprop, turbofan) engines, and possible benefits of the Global Position Satellite System to general aviation navigation are covered in the discussion. Some of the developments are illustrated.

Stickle, J. W.↗
NASA NTRS1981

Performance and loads data from a wind tunnel test of a full-scale, coaxial, hingeless rotor helicopter

A full-scale XH-59A advancing blade concept helicopter was tested in Ames Research Center's 40 by 80 foot wind tunnel. The helicopter was tested with the rotor on and off, rotor hub fairings on and off, interrotor shaft fairing on and off, rotor instrumentation module on and off, and auxiliary propulsion thrust on and off. An advance ratio range of 0.25 and 0.45 with the rotor on and from 60 to 180 knots with the rotor off was investigated. Data on aerodynamic forces and moments, rotor loads, rotor control positions and vibration for the XH-59A as well as the aerodynamic performance of the isolated rotor are presented.

Felker, F. F., III↗
NASA NTRS1984

Orbital transfer vehicle propulsion issues

The development of a reusable and space-based orbital transfer vehicle (OTV) necessitates an integral approach toward structural and propulsion subsystems design. A single engine installation necessitates moving the engine further aft and/or relocation of the engine gimbal point to accommodate vehicle control requirements. Penalties associated with gimbal point relocation without increasing stage length or modifying typical advanced engine concepts, as well as a method for minimizing such penalties, are presented for a single engine toroidal tank OTV configuration. Alternative integrated vehicle structure/engine concepts are also presented for multi-engine configurations. Features of these potential concepts are given which indicate the need for substantial additional study of feedline gimbal alternatives before firmly establishing advanced engine design. The issue of vehicle/engine integration is addressed in three areas: interfaces (physical and functional), installation requirements, and reliability apportionment (i.e., number of engines required to assure mission completion).

Bergeron, R. P.↗
NASA NTRS1995

Balloon Experiment at Venus

NASA/Jet Propulsion Laboratory is designing a return mission to the Venusian atmosphere using a reversible fluid altitude control balloon called Balloon Experiment at Venus (BEV). This is a proposed NASA flight experiment to demonstrate key technologies for operation of advanced balloons in the atmosphere of Venus. This paper includes both the mission profile and system description of the proposed BEV concept.

Venus planetary probes balloon↗
NASA NTRS2014

Tone and Broadband Noise Separation from Acoustic Data of a Scale-Model Counter-Rotating Open Rotor

Renewed interest in contra-rotating open rotor technology for aircraft propulsion application has prompted the development of advanced diagnostic tools for better design and improved acoustical performance. In particular, the determination of tonal and broadband components of open rotor acoustic spectra is essential for properly assessing the noise control parameters and also for validating the open rotor noise simulation codes. The technique of phase averaging has been employed to separate the tone and broadband components from a single rotor, but this method does not work for the two-shaft contra-rotating open rotor. A new signal processing technique was recently developed to process the contra-rotating open rotor acoustic data. The technique was first tested using acoustic data taken of a hobby aircraft open rotor propeller, and reported previously. The intent of the present work is to verify and validate the applicability of the new technique to a realistic one-fifth scale open rotor model which has 12 forward and 10 aft contra-rotating blades operating at realistic forward flight Mach numbers and tip speeds. The results and discussions of that study are presented in this paper.

Acoustic Data↗
NASA NTRS2014

Tone and Broadband Noise Separation from Acoustic Data of a Scale-Model Contra-Rotating Open Rotor

Renewed interest in contra-rotating open rotor technology for aircraft propulsion application has prompted the development of advanced diagnostic tools for better design and improved acoustical performance. In particular, the determination of tonal and broadband components of open rotor acoustic spectra is essential for properly assessing the noise control parameters and also for validating the open rotor noise simulation codes. The technique of phase averaging has been employed to separate the tone and broadband components from a single rotor, but this method does not work for the two-shaft contra-rotating open rotor. A new signal processing technique was recently developed to process the contra-rotating open rotor acoustic data. The technique was first tested using acoustic data taken of a hobby aircraft open rotor propeller, and reported previously. The intent of the present work is to verify and validate the applicability of the new technique to a realistic one-fifth scale open rotor model which has 12 forward and 10 aft contra-rotating blades operating at realistic forward flight Mach numbers and tip speeds. The results and discussions of that study are presented in this paper.

Noise Separation↗
NASA NTRS2015

Technology Demonstration Missions

Technology Demonstration Missions (TDM) is in its third year of execution, being initiated in 2010 and baselined in January of 2012. There are 11 projects that NASA Marshall Space Flight Center (MSFC) has contributed to or led: (1) Evolvable Cryogenics (eCryo): Cyrogenic Propellant Storage and Transfer Engineering Development Unit (EDU), a proof of manufacturability effort, used to enhance knowledge and technology related to handling cryogenic propellants, specifically liquid hydrogen. (2) Composites for Exploration Upper Stage (CEUS): Design, build, test, and address flight certification of a large composite shell suitable for the second stage of the Space Launch System (SLS). (3) Deep Space Atomic Clock (DSAC): Spaceflight to demo small, low-mass atomic clock that can provide unprecedented stability for deep space navigation. (4) Green Propellant Infusion Mission (GPIM): Demo of high-performance, green propellant propulsion system suitable for Evolved Expendable Launch Vehicle (EELV) Secondary Payload Adapter (ESPA)-class spacecraft. (5) Human Exploration Telerobotics (HET): Demonstrating how telerobotics, remote control of a variety of robotic systems, can take routine, highly repetitive, dangerous or long-duration tasks out of human hands. (6) Laser Communication Relay Demo (LCRD): Demo to advance optical communications technology toward infusion into deep space and near Earth operational systems, while growing the capabilities of industry sources. (7) Low Density Supersonic Decelerator (LDSD): Demo new supersonic inflatable decelerator and parachute technologies to enable Mars landings of larger payloads with greater precision at a wider range of altitudes. (8) Mars Science Laboratory (MSL) Entry Descent & Landing Instrumentation (MEDLI): Demo of embedded sensors embedded in the MSL heat shield, designed to record the heat and atmospheric pressure experienced during the spacecraft's high-speed, hot entry in the Martian atmosphere. (9) Solar Electric Propulsion (SEP): 50-kW class spacecraft that uses flexible blanket solar arrays for power generation and an electric propulsion system that delivers payload from low-Earth orbit to higher orbits. (10) Solar Sail Demonstration (SSD): Demo to validate sail deployment techniques for solar sails that are propelled by the pressure of sunlight. (11) Terrestrial HIAD Orbit Reentry (THOR): Demo of a 3.7-m Hypersonic Inflatable Aerodynamic Decelerator (HIAD) entry vehicle to test second generation aerothermal performance and modeling.

McDougal, John↗
DOE OSTI2024

EV SALaD 2023 Demonstration: Best Practices and Mitigations for Protecting EVSE Infrastructure

The Electric Vehicle Secure Architecture Laboratory Demonstration (EV SALaD) program is a demonstration of cybersecurity best practices for high-power electric vehicle (EV) charging infrastructure led by Idaho National Laboratory (INL), in collaboration with other DOE National Laboratories participating in the EVs at Scale Consortium.a Sandia National Laboratories (SNL) and Pacific Northwest National Laboratory (PNNL) participated in the first 2-year (FY22-23) demonstration cycle for EV SALaD. This report documents the FY23 demonstration, the second in a series of demonstrations and collaborations in deploying and operating cybersecure EV charging infrastructure. It includes a summary of improvements from the FY22 demonstration, technical analysis of the FY23 demonstration, how the research demonstrates cyber-physical and cybersecurity best practices for high-power EV charging infrastructure, and related impacts to national and energy security. For EV SALaD, the FY22 demonstration focused on the detection, ranking, and prioritization of anomalous events for high-power EV charging. The FY23 demonstration additionally included the demonstration of cybersecurity best practices, which included protection and mitigation solutions to prevent, respond, and recover from anomalous events. During the demonstrations, the multi-lab EV SALaD team conducted a Test Effect Payload (TEP)b evaluation on extreme fast charger (XFC) hardware equipped with Cerberus, a detection and response solution, to demonstrate anomaly detection and mitigation cybersecurity best practices against cyber-enabled events.

33 ADVANCED PROPULSION SYSTEMS↗
NASA NTRS1975

Quiet clean short-haul experimental engine /QCSEE/ design rationale

The principal design features of the NASA QCSEE Under-The-Wing and Over-The-Wing powered lift propulsion systems are given. In the UTW engine, these include noise reduction features, a variable pitch low pressure ratio fan, a fan drive reduction gear, an advanced core and low pressure turbine with a low pollution combustor, a digital control, and advanced composite construction for the inlet, fan frame, fan exhaust duct, and variable area fan exhaust nozzle. The OTW engine is similar but has higher fan pressure and a fixed pitch fan. Both engines are scheduled to be fabricated and tested starting in 1976.

Adamson, A. P.↗
NASA NTRS1986

Aerodynamic design trends for commercial aircraft

Recent research on advanced-configuration commercial aircraft at DFVLR is surveyed, with a focus on aerodynamic approaches to improved performance. Topics examined include transonic wings with variable camber or shock/boundary-layer control, wings with reduced friction drag or laminarized flow, prop-fan propulsion, and unusual configurations or wing profiles. Drawings, diagrams, and graphs of predicted performance are provided, and the need for extensive development efforts using powerful computer facilities, high-speed and low-speed wind tunnels, and flight tests of models (mounted on specially designed carrier aircraft) is indicated.

Hilbig, R.↗
NASA NTRS2006

2005 NASA Seal/Secondary Air System Workshop, Volume 1

The 2005 NASA Seal/Secondary Air System workshop covered the following topics: (i) Overview of NASA s new Exploration Initiative program aimed at exploring the Moon, Mars, and beyond; (ii) Overview of the NASA-sponsored Propulsion 21 Project; (iii) Overview of NASA Glenn s seal project aimed at developing advanced seals for NASA s turbomachinery, space, and reentry vehicle needs; (iv) Reviews of NASA prime contractor, vendor, and university advanced sealing concepts including tip clearance control, test results, experimental facilities, and numerical predictions; and (v) Reviews of material development programs relevant to advanced seals development. Turbine engine studies have shown that reducing high-pressure turbine (HPT) blade tip clearances will reduce fuel burn, lower emissions, retain exhaust gas temperature margin, and increase range. Several organizations presented development efforts aimed at developing faster clearance control systems and associated technology to meet future engine needs. The workshop also covered several programs NASA is funding to develop technologies for the Exploration Initiative and advanced reusable space vehicle technologies. NASA plans on developing an advanced docking and berthing system that would permit any vehicle to dock to any on-orbit station or vehicle. Seal technical challenges (including space environments, temperature variation, and seal-on-seal operation) as well as plans to develop the necessary "androgynous" seal technologies were reviewed. Researchers also reviewed tests completed for the shuttle main landing gear door seals.

Steinetz, Bruce M.↗
NASA NTRS2016

HIAD Advancements and Extension of Mission Applications

The Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology has made significant advancements over the last decade with flight test demonstrations and ground development campaigns. The first generation (Gen-1) design and materials were flight tested with the successful third Inflatable Reentry Vehicle Experiment flight test of a 3-m HIAD (IRVE-3). Ground development efforts incorporated materials with higher thermal capabilities for the inflatable structure (IS) and flexible thermal protection system (F-TPS) as a second generation (Gen-2) system. Current efforts and plans are focused on extending capabilities to improve overall system performance and reduce areal weight, as well as expand mission applicability. F-TPS materials that offer greater thermal resistance, and ability to be packed to greater density, for a given thickness are being tested to demonstrated thermal performance benefits and manufacturability at flight-relevant scale. IS materials and construction methods are being investigated to reduce mass, increase load capacities, and improve durability for packing. Previous HIAD systems focused on symmetric geometries using stacked torus construction. Flight simulations and trajectory analysis show that symmetrical HIADs may provide L/D up to 0.25 via movable center of gravity (CG) offsets. HIAD capabilities can be greatly expanded to suit a broader range of mission applications with asymmetric shapes and/or modulating L/D. Various HIAD concepts are being developed to provide greater control to improve landing accuracy and reduce dependency upon propulsion systems during descent and landing. Concepts being studied include a canted stack torus design, control surfaces, and morphing configurations that allow the shape to be actively manipulated for flight control. This paper provides a summary of recent HIAD development activities, and plans for future HIAD developments including advanced materials, improved construction techniques, and alternate geometry concepts that will greatly expand HIAD mission applications.

Johnson, R. Keith↗
DOE OSTI2023

Controller Hardware-in-the-Loop Modeling and Operation of a High-Power DC Charging Hub

High-power charging (HPC) concept will be a critical enabler for the wide-scale adoption and integration of electric vehicles (EVs). HPC hubs will have a significant impact on achieving this goal, particularly when considering the charging requirements of next-generation medium and heavy-duty vehicles (MD/HD) used in various vocational scenarios. This emphasizes the significance of evaluating and confirming the technical planning and multi-level operation of HPC hubs through modeling, protocol implementation, and simulation before hardware demonstration. The focus of this study is to develop the architecture, modeling, communication, and real-time controller hardware-in-the-loop (C-HIL) simulation of HPC hubs using the DC distribution system approach. Specifically, this work demonstrates the practical implementation of a custom Smart Energy Management System (SEMS) for a real-time C-HIL HPC hub simulation using the Open Charge Point Protocol (OCPP) for communication. OCPP is implemented on the Node-Red framework and the custom controller is executed in Python. We developed a rule-based controller to demonstrate the proposed approach.

ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2020

Powertrain control system and method of operating the same

A system and method are provided for operating a powertrain control system. The method includes receiving data measured from a plurality of sensors, the measured data relating to distance dependent speed values, and receiving information from one or more vehicle modules, the vehicle module information relating to distance independent speed values. The method further includes building a speed trajectory profile for a horizon window that includes a plurality of speed change regions represented by at least some distance dependent speed values or at least some distance independent speed values, and creating a synthesized speed profile for the horizon window by processing the speed trajectory profile. The synthesized speed profile optimizes efficiency of the powertrain control system at each of the plurality of speed change regions.

33 ADVANCED PROPULSION SYSTEMS↗
NASA NTRS2014

Enabling Advanced Wind-Tunnel Research Methods Using the NASA Langley 12-Foot Low Speed Tunnel

Design of Experiment (DOE) testing methods were used to gather wind tunnel data characterizing the aerodynamic and propulsion forces and moments acting on a complex vehicle configuration with 10 motor-driven propellers, 9 control surfaces, a tilt wing, and a tilt tail. This paper describes the potential benefits and practical implications of using DOE methods for wind tunnel testing - with an emphasis on describing how it can affect model hardware, facility hardware, and software for control and data acquisition. With up to 23 independent variables (19 model and 2 tunnel) for some vehicle configurations, this recent test also provides an excellent example of using DOE methods to assess critical coupling effects in a reasonable timeframe for complex vehicle configurations. Results for an exploratory test using conventional angle of attack sweeps to assess aerodynamic hysteresis is summarized, and DOE results are presented for an exploratory test used to set the data sampling time for the overall test. DOE results are also shown for one production test characterizing normal force in the Cruise mode for the vehicle.

Busan, Ronald C.↗
NASA NTRS2019

Slow Crack Growth of Boron Nitrides for Electric Propulsion Components

The Deep Space Gateway requires thruster systems to maintain spatial position. One control system being considered involves Hall thrusters. Historically, Hall thruster discharge channels have used several grades of hot-pressed hexagonal boron nitride. This study compliments data presented at ICACC (International Conference and Expo on Advanced Ceramics and Composites) 2018 and investigates the fracture toughness and slow crack growth parameters of several commercially available boron nitride grades including HP, M, M26, and Shapal Hi-M. The prior work revealed that some grades of BN absorb water and change strength thus presenting a philosophical conundrum on crack growth test methods. Advantages of different test methods will be discussed. The grades selected for this study are of interest because their available billet size is sufficient for Hall thruster discharge channels, or because they have heritage in Hall thruster applications. Ultimately, the data will be used to perform material selection, system design and reliability analyses.

Ceramics↗
NASA NTRSDate not supplied

Update on SUSAN Concept Vehicle Power and Propulsion System

This paper provides an update on the power and propulsion (P&P) system design for the SUbsonic Single Aft eNgine (SUSAN) Electrofan. The SUSAN vehicle concept is a transformative concept hybrid electric aircraft with a single tail-mounted turbofan engine that provides thrust and power to 16 electric propulsors located on the wings. This configuration makes uses of large-scale power extraction along with a high-power electrical system transmitting 20 MW of power from the engine to the wing propulsors. This paper goes into detail on P&P advances relating turbine engine design, electrical system capabilities, advanced turbine control techniques, and electrical system cooling techniques. It should be noted that the SUSAN concept continues to be developed and this paper simply offers an update on the design.

aircraft concept↗
NASA NTRS1972

The new civil aviation within our grasp.

Noise and congestion present the two main technological constraints on air-transportation growth. Although some of the noise reduction will come with improved flight-path control and steep approaches, the main requirement remains quiet propulsion systems. Higher engine temperatures will compensate for efficiency losses due to noise suppression. Composite structures can reduce structural weight by 20%. New developments in rotorcraft transports are discussed together with advanced subsonic transports of the 1980s and the possibilities for further evolution of the SSTs, leading to a hypersonic aircraft.

Cortright, E. M.↗