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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Engineering Elegant Systems: Postulates, Principles, and Hypotheses of Systems Engineering

Definition: System Engineering is the engineering discipline which integrates the system functions, system environment, and the engineering disciplines necessary to produce and/or operate an elegant system; Elegant System - A system that is robust in application, fully meeting specified and adumbrated intent, is well structured, and is graceful in operation. Primary Focus: System Design and Integration: Identify system couplings and interactions; Identify system uncertainties and sensitivities; Identify emergent properties; Manage the effectiveness of the system. Engineering Discipline Integration: Manage flow of information for system development and/or operations; Maintain system activities within budget and schedule. Supporting Activities: Process application and execution.

Watson, Michael D.↗
NASA NTRS2016

Creating Systems Engineering Products with Executable Models in a Model-Based Engineering Environment

Applying systems engineering across the life-cycle results in a number of products built from interdependent sources of information using different kinds of system level analysis. This paper focuses on leveraging the Executable System Engineering Method (ESEM) which automates requirements verification (e.g. power and mass budget margins and duration analysis of operational modes) using executable SysML models. The particular value proposition is to integrate requirements, and executable behavior and performance models for certain types of system level analysis. The models are created with modeling patterns that involve structural, behavioral and parametric diagrams, and are managed by an open source Model Based Engineering Environment (named OpenMBEE). This paper demonstrates how the ESEM is applied in conjunction with OpenMBEE to create key engineering products (e.g. operational concept document) for the Alignment and Phasing System (APS) within the Thirty Meter Telescope (TMT) project, which is under development by the TMT International Observatory (TIO).

MBSE↗
NASA NTRSDate not supplied

Tail-mounted engine Architecture and Design for the Subsonic Single Aft Engine Electrofan Aircraft

This paper describes the turbofan engine architecture for SUbsonic Single Aft eNgine (SUSAN) Electrofan is, a transformative concept hybrid electric aircraft. SUSAN has a single tail-mounted turbofan engine that produces a portion of the requires thrust and drives a 20MW electric generator which in turn provides the power to the 16 electric propulsors located on the wing responsible for producing the remainder of the required thrust. The atypical operation of the turbofan due to the large levels of power extraction from the low pressure turbine (LPT) is described here. This paper investigates the most efficient engine architecture to enable this unique operation, as well as exploring natural gas as an alternative fuel for SUSAN.

EAP↗
DOE OSTI2025

Rheology and engine performance of very low sulfur fuel oil blended with 10% fast pyrolysis and hydrothermal liquefaction oils in a 2-stroke crosshead engine

The performance and emissions for a downscaled single-cylinder 2-stroke crosshead engine were determined for a very low sulfur fuel oil (VLSFO) when blended with 10 wt.% fast pyrolysis (FP) or hydrothermal liquefaction (HTL) bio-intermediates. The FP and HTL oils were derived from biomass and were observed to contain lower molecular weight (MW) hydrocarbons than neat VLSFO (which was evaluated as a baseline comparison). The addition of either biofuel reduced the overall viscosity of the VLSFO. Aging tests at 50, 90, and 120°C showed that the dynamic viscosity of VLSFO increased with exposure time up to two weeks. Similar trends were observed for the FP and HTL blends, but a pronounced spike in viscosity occurred for these fuels during the early period of exposure. None of the viscosity increases exceeded the operational limits of fuel system pumps. Engine performance studies were conducted under low, medium and high load operational settings. The relative performance of the test fuels was highly dependent on operating condition. In general, the engine results for the three test fuels were similar, but modest improvements in brake thermal efficiency and brake specific fuel consumption were observed, which may be attributed to the heightened reactivity of low molecular weight fraction of the FP and HTL oils.

09 BIOMASS FUELS↗
DOE OSTI2020

An Interaction-Free Quantum Measurement-Driven Engine

Recently highly-efficient quantum engines were devised by exploiting the stochastic energy changes induced by quantum measurement. Here we show that such an engine can be based on an interaction-free measurement, in which the meter seemingly does not interact with the measured object. We use a modified version of the Elitzur–Vaidman bomb tester, an interferometric setup able to detect the presence of a bomb triggered by a single photon without exploding it. In our case, a quantum bomb subject to a gravitational force is initially in a superposition of being inside and outside one of the interferometer arms. We show that the bomb can be lifted without blowing up. This occurs when a photon traversing the interferometer is detected at a port that is always dark when the bomb is located outside the arm. The required potential energy is provided by the photon (which plays the role of the meter) even though it was not absorbed by the bomb. A natural interpretation is that the photon traveled through the arm which does not contain the bomb—otherwise the bomb would have exploded—but it implies the surprising conclusion that the energy exchange occurred at a distance despite a local interaction Hamiltonian. We use the weak value formalism to support this interpretation and find evidence of contextuality. Regardless of interpretation, this interaction-free quantum measurement engine is able to lift the most sensitive bomb without setting it off.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
NASA NTRS1951

Experimental Investigation of Air-cooled Turbine Blades in Turbojet Engine IX : Evaluation of the Durability of Noncritical Rotor Blades in Engine Operation

The durability of five different structural or cooling configurations or combination of both of air-cooled blades made of noncritical materials was investigated in a modified turbojet engine. The greater part of the investigation was conducted at an engine speed of 11,500 rpm, a turbine-inlet temperature of approximately 1670 degrees F, and a cooling-air to combustion gas flow ratio per blade of 0.05. The results of the investigation indicated that air-cooled blades made of noncritical metals can be operated for extended periods of time in engines at current inlet temperatures; however, before these blades are considered completely satisfactory for gas-turbine application, some means such as coatings is required to inhibit the oxidation of the blades.

TURBINES - BLADES - COOLING↗
DOE OSTI2026

Artificial intelligence tools for enzyme engineering and metabolic engineering

Enzyme engineering and metabolic engineering drive innovation in energy biotechnology. In recent years, artificial intelligence (AI) has supported successful applications in designing effective enzymes and productive microbial cell factories. This review summarizes recent advances in enzyme redesign using protein language models, de novo enzyme design with generative models, and AI tools for engineering metabolism and related cellular phenotypes. Across these areas, AI models are shifting from single modality inputs to integrated representations of protein function, metabolic pathways, and cell states. We emphasize that unifying the diverse data representations across scales will be necessary for advancements in energy biotechnology.

Volk, Michael [Univ. of Illinois at Urbana-Champai↗
DOE OSTI2025

Do Research Software Engineers and Software Engineering Researchers Speak the Same Language?

Anecdotal evidence suggests that research software engineers (RSEs) and software engineering researchers (SERs) often use different terminologies for similar concepts, creating communication challenges. To better understand these divergences, we have started investigating how software engineering fundamentals from the SER community are interpreted within the RSE community, identifying aligned concepts, knowledge gaps, and areas for potential adaptation. In conclusion, our preliminary findings reveal opportunities for mutual learning and collaboration, and our systematic methodology for terminology mapping provides a foundation for a crowdsourced extension and validation in the future.

Kehrer, Timo [Univ. of Bern (Switzerland)] (ORCID:↗
DOE OSTI2021

Stacking-engineered ferroelectricity in bilayer boron nitride

Stacking a ferroelectric Properties of layered van der Waals structures can depend sensitively on the stacking arrangement of constituent layers. This phenomenon has been exploited to engineer superconducting, correlated insulator, and magnetic states. Two groups now show that ferroelectricity can also be engineered through stacking: Parallel-stacked bilayers of hexagonal boron nitride exhibit ferroelectric switching even though the bulk material is not ferroelectric (see the Perspective by Tsymbal). To explore these phenomena, Yasuda et al. used transport measurements, whereas Vizner Stern et al. focused on atomic force microscopy. Science , abd3230 and abe8177, this issue p. 1458 and p. 1462 ; see also abi7296, p. 1389

Science & Technology - Other Topics↗
NASA NTRS1972

Experimental evaluation of a TF30-P-3 turbofan engine in an altitude facility: Afterburner performance and engine-afterburner operating limits

For distortion free steady state operation at the maximum (full afterburning) throttle position, the afterburner combustion efficiency decreased from 0.91 to 0.68 as engine inlet Reynolds number index was reduced from 0.80 to 0.25. Engine afterburner operational limits were obtained for transient and fixed throttle operation over a range of engine inlet distortions. At limiting conditions, time histories of pressures in the fan compressor during throttle transients between military and maximum showed the development of rotating stall in the fan hub which quickly propagated and produced complete stall in the high pressure compressor.

Mcaulay, J. E.↗
NASA NTRS1973

An airline study of advanced technology requirements for advanced high speed commercial transport engines. 2: Engine preliminary design assessment

The advanced technology requirements for an advanced high speed commercial transport engine are presented. The results of the phase 2 study effort cover the following areas: (1) general review of preliminary engine designs suggested for a future aircraft, (2) presentation of a long range view of airline propulsion system objectives and the research programs in noise, pollution, and design which must be undertaken to achieve the goals presented, (3) review of the impact of propulsion system unreliability and unscheduled maintenance on cost of operation, (4) discussion of the reliability and maintainability requirements and guarantees for future engines.

Sallee, G. P.↗
NASA NTRS1977

Variation of pitching moment with engine thrust for a twin-engine commercial jet aircraft

Flight tests were made to determine the effect of engine net thrust on airplane pitching moment for a twin-engine commercial jet transport in the approach, climbout and descent, and cruise configurations. The results indicate that for all the conditions analyzed, the pitching moment due to thrust is somewhat higher than that estimated from the product of net thrust and its moment arm (perpendicular distance from thrust axis to the airplane center of gravity). The differences are attributed to additional moments produced by nacelle normal force, jet-induced downwash, and interaction between wing flow and engine nacelle flow.

Shanks, R. E.↗
NASA NTRS1979

A summary of NASA/Air Force full scale engine research programs using the F100 engine

A full scale engine research (FSER) program conducted with the F100 engine is presented. The program mechanism is described and the F100 test vehicles utilized are illustrated. Technology items were addressed in the areas of swirl augmentation, flutter phenomenon, advanced electronic control logic theory, strain gage technology and distortion sensitivity. The associated test programs are described. The FSER approach utilizes existing state of the art engine hardware to evaluate advanced technology concepts and problem areas. Aerodynamic phenomenon previously not considered by design systems were identified and incorporated into industry design tools.

Deskin, W. J.↗
NASA NTRS1979

A summary of NASA/Air Force Full Scale Engine Research programs using the F100 engine

This paper summarizes a joint NASA/Air Force Full Scale Engine Research (FSER) program conducted with the F100 engine during the period 1974 through 1979. The program mechanism is described and the F100 test vehicles utilized are illustrated. Technology items which have been addressed in the areas of swirl augmentation, flutter phenomenon, advanced electronic control logic theory, strain gage technology, and distortion sensitivity are identified and the associated test programs conducted at the NASA-Lewis Research Center are described. Results presented show that the FSER approach, which utilizes existing state-of-the-art engine hardware to evaluate advanced technology concepts and problem areas, can contribute a significant data base for future system applications. Aerodynamic phenomenon previously not considered by current design systems have been identified and incorporated into current industry design tools.

Deskin, W. J.↗
NASA NTRS1978

Quiet, Clean, Short-Haul Experimental Engine (QCSEE) Over-The-Wing (OTW) engine acoustic design

The acoustic considerations involved in the low source noise basic engine design and the design procedures followed in the development of the over-the-wing (OTW) nacelle acoustic treatment design are presented. Laboratory experiments, component tests, and scale model and engine tests supporting the OTW engine acoustic design are referenced. Acoustic design features include a near-sonic inlet, low fan and core pressure ratios, low fan tip speed, high and low frequency stacked core treatment, multiple thickness treatment, and fan frame and stator vane treatment.

Sowers, H. D.↗