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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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NASA NTRS2015

Model-Based Systems Engineering in Concurrent Engineering Centers

Concurrent Engineering Centers (CECs) are specialized facilities with a goal of generating and maturing engineering designs by enabling rapid design iterations. This is accomplished by co-locating a team of experts (either physically or virtually) in a room with a narrow design goal and a limited timeline of a week or less. The systems engineer uses a model of the system to capture the relevant interfaces and manage the overall architecture. A single model that integrates other design information and modeling allows the entire team to visualize the concurrent activity and identify conflicts more efficiently, potentially resulting in a systems model that will continue to be used throughout the project lifecycle. Performing systems engineering using such a system model is the definition of model-based systems engineering (MBSE); therefore, CECs evolving their approach to incorporate advances in MBSE are more successful in reducing time and cost needed to meet study goals. This paper surveys space mission CECs that are in the middle of this evolution, and the authors share their experiences in order to promote discussion within the community.

Iwata, Curtis↗

NASA NTRS2015

Model-Based Systems Engineering in Concurrent Engineering Centers

MODEL↗

NASA NTRS1986

Compound cycle engine for helicopter application

The Compound Cycle Engine (CCE) is a highly turbocharged, power compounded, ultra-high power density, light-weight diesel engine. The turbomachinery is similar to a moderate pressure ratio, free power turbine engine and the diesel core is high speed and a low compression ratio. This engine is considered a potential candidate for future military light helicopter applications. This executive summary presents cycle thermodynamic (SFC) and engine weight analyses performed to establish general engine operating parameters and configuration. An extensive performance and weight analysis based on a typical two hour helicopter (+30 minute reserve) mission determined final conceptual engine design. With this mission, CCE performance was compared to that of a T-800 class gas turbine engine. The CCE had a 31% lower-fuel consumption and resulted in a 16% reduction in engine plus fuel and fuel tank weight. Design SFC of the CCE is 0.33 lb-HP-HR and installed wet weight is 0.43 lbs/HP. The major technology development areas required for the CCE are identified and briefly discussed.

Castor, Jere G.↗

NASA NTRS2002

Acoustic and Laser Doppler Anemometer Results for Confluent, 22-Lobed, and Unique-Lobed Mixer Exhaust Systems for Subsonic Jet Noise Reduction

The objective of this task was to develop a design methodology and noise reduction concepts for high bypass exhaust systems which could be applied to both existing production and new advanced engine designs. Special emphasis was given to engine cycles with bypass ratios in the range of 4:1 to 7:1, where jet mixing noise was a primary noise source at full power takeoff conditions. The goal of this effort was to develop the design methodology for mixed-flow exhaust systems and other novel noise reduction concepts that would yield 3 EPNdB noise reduction relative to 1992 baseline technology. Two multi-lobed mixers, a 22-lobed axisymmetric and a 21-lobed with a unique lobe, were designed. These mixers along with a confluent mixer were tested with several fan nozzles of different lengths with and without acoustic treatment in GEAE's Cell 41 under the current subtask (Subtask C). In addition to the acoustic and LDA tests for the model mixer exhaust systems, a semi-empirical noise prediction method for mixer exhaust system is developed. Effort was also made to implement flowfield data for noise prediction by utilizing MGB code. In general, this study established an aero and acoustic diagnostic database to calibrate and refine current aero and acoustic prediction tools.

Salikuddin, M.↗

NASA NTRS2014

Designing Liquid Rocket Engine Injectors for Performance, Stability, and Cost

NASA is developing the Space Launch System (SLS) for crewed exploration missions beyond low Earth orbit. Marshall Space Flight Center (MSFC) is designing rocket engines for the SLS Advanced Booster (AB) concepts being developed to replace the Shuttle-derived solid rocket boosters. One AB concept uses large, Rocket-Propellant (RP)-fueled engines that pose significant design challenges. The injectors for these engines require high performance and stable operation while still meeting aggressive cost reduction goals for access to space. Historically, combustion stability problems have been a critical issue for such injector designs. Traditional, empirical injector design tools and methodologies, however, lack the ability to reliably predict complex injector dynamics that often lead to combustion stability. Reliance on these tools alone would likely result in an unaffordable test-fail-fix cycle for injector development. Recently at MSFC, a massively parallel computational fluid dynamics (CFD) program was successfully applied in the SLS AB injector design process. High-fidelity reacting flow simulations were conducted for both single-element and seven-element representations of the full-scale injector. Data from the CFD simulations was then used to significantly augment and improve the empirical design tools, resulting in a high-performance, stable injector design.

Westra, Douglas G.↗

DOE OSTI2020

Spawn [SWR-SWR-20-10]

Spawn is a next generation building simulation engine designed to build on the strengths of NREL's venerable EnergyPlus engine, and add new advanced HVAC and controls modeling capability by incorporating the Modelica equation based modeling language. In effect, Spawn is a hybrid of the existing EnergyPlus and Modelica software products, with some new software to provide glue between the components in order to provide a seamless end user experience.

Li, Yanfei↗

DOE OSTI2020

BioSTEAMDevelopmentGroup/thermosteam

BioSTEAM is a fast and flexible package for the design, simulation, and techno-economic analysis of biorefineries under uncertainty. BioSTEAM’s framework is built to streamline and automate early-stage technology evaluations and to enable rigorous sensitivity and uncertainty analyses. Complete biorefinery configurations are available at the Bioindustrial-Park GitHub repository, BioSTEAM’s premier repository for biorefinery models and results. The long-term growth and maintenance of BioSTEAM is supported through both community-led development and the research institutions invested in BioSTEAM. Through the open-source and community-lead platform, BioSTEAM aims to foster communication and transparency within the biorefinery research community for an integrated effort to expedite the evaluation of candidate biofuels and bioproducts. Additionally, an agile life cycle assessment (LCA) platform has been designed to interface with BioSTEAM, BioSTEAM-LCA. This open-source, installable package allows users to perform streamlined LCAs of biorefineries. The focus of BioSTEAM-LCA is to streamline and automate early-stage environmental impact analyses of processes and technologies, and to enable rigorous sensitivity and uncertainty analyses linking process design, performance, economics, and environmental impacts. ThermoSTEAM is a standalone thermodynamic engine capable of estimating mixture properties, solving thermodynamic phase equilibria, and modeling stoichiometric reactions. ThermoSTEAM builds upon chemicals, the chemical properties component of the Chemical Engineering Design Library, with a robust and flexible framework that facilitates the creation of property packages. The Biorefinery Simulation and Techno-Economic Analysis Modules (BioSTEAM) is dependent on ThermoSTEAM for the simulation of unit operations.

Cortes-Peña, Yoel↗

DOE OSTI2024

CW copper injector for SRF industrial cryomodules

Compact SRF industrial linacs can provide unique parameters of the beam (>1 MW and >1-10 MeV) hardly achievable by normal conducting linacs within limited space. SRF technology was prohibitively expensive until the development of conduction cooling which opened the way for compact stand alone SRF systems suitable for industrial and research applications. Limited cooling capacity puts strict requirements on the beam parameters with zero losses of the beam on the SRF cavity walls. This implies strict requirements on the beam energy to be accepted by the cryomodule and most importantly the beam bunching with zero particles in between. We designed a CW normal conducting RF injector which consists of a gridded RF gun integrated with a first cell of a copper booster cavity to satisfy these requirements. Here we present a complete design of a booster cavity including beam dynamics, RF, thermomechanical and engineering design.

43 PARTICLE ACCELERATORS↗

NASA NTRS1973

The Space Shuttle Main Engine

A reusable high-performance rocket engine intended for putting the Space Shuttle orbiter vehicle into earth orbit is described. Three such engines are clustered in the aft end of the orbiter stage. They burn in parallel with the solid-propellant boosters during the initial ascent phase and continue to burn after booster ejection until just prior to orbit insertion. The nominal burn time is roughly 10 min. Propulsion requirements demand maximum performance from liquid oxygen/hydrogen propellants with a minimum hardware weight. The engine design and the present progress made in the development of the engine are discussed.

Castenholz, P. D.↗

NASA NTRS1975

QCSSE program

The objectives, scope, and status of the NASA Quiet, Clean, Short-Haul Experimental Engine program are reviewed. The progress reported is concerned with engine design concepts for short-haul aircraft where part of the engine thrust is used to help lift the aircraft. Both under-the-wing, and over-the-wing configurations are discussed.

Ciepluch, C. C.↗

NASA NTRS1978

A summary of systems definition project activities

Design information and subsystem requirement definition to the overall program is presented. Application analysis and conceptual design for the wide variety of systems, system tradeoff studies and engineering design for the more promising application types, and the identification of the technology status and requirements for major subsystems and components are described. The residential design and analysis contracts, hybrid photovoltaic/solar thermal electric conversion contract, and development of prototype combined photovoltaic/thermal flat-plate collectors were studied.

Jones, G. J.↗

NASA NTRS1980

A spin-recovery parachute system for light general-aviation airplanes

A tail mounted spin recovery parachute system was designed and developed by the NASA Langley Research Center for use on light general aviation airplanes. The system was designed for use on typical airplane configurations, including low wing, single engine, and twin-engine design. A mechanically triggered pyrotechnic slug gun is used to forcibly deploy a pilot parachute which extracts a bag that deploys a ring slot spin recovery parachute. The total system weighs 8.2 kg (18 lb). System design factors included airplane wake effects on parachute deployment, prevention of premature parachute deployment, positive parachute jettison, compact size, low weight, system reliability, and pilot and ground crew safety. Extensive ground tests were conducted to qualify the system. The recovery parachute was used successfully in flight 17 times.

Bradshaw, C.↗

NASA NTRS1982

Integrated airframe propulsion control

Perturbation equations which describe flight dynamics and engine operation about a given operating point are combined to form an integrated aircraft/propulsion system model. Included in the model are the dependence of aerodynamic coefficients upon atmospheric variables along with the dependence of engine variables upon flight condition and inlet performance. An off-design engine performance model is used to identify interaction parameters in the model. Inclusion of subsystem interaction effects introduces coupling between flight and propulsion variables. To analyze interaction effects on control, consideration is first given to control requirements for separate flight and engine models. For the separate airframe model, feedback control provides substantial improvement in short period damping. For the integrated system, feedback control compensates for the coupling present in the model and provides good overall system stability. However, this feedback control law involves many non-zero gains. Analysis of suboptimal control strategies indicates that performance of the closed loop integrated system can be maintained with a feedback matrix in which the number of non-zero gains is small relative to the number of components in the feedback matrix.

Fennell, R. E.↗

NASA NTRS1984

Subatmospheric Brayton-cycle Engine Program Review

A solar energy powered electrical generator utilizing a Subatmospheric Brayton cycle engine is examined. The generator consists of a subatmospheric, Brayton-cycle engine and a permanent magnet (PM) alternator. The electrical power is generated by an alternator driven directly by the Brayton-cycle engine rotating group. Features that enhance reliability and performance include air foil bearings on both the Brayton-cycle engine rotating group and the PM alternator, an atmospheric-pressure solar receiver and gas-fired trim heater, and a high temperature recuperator. The subatmospheric Brayton-cycle engine design is based on that of the gas fired heat pump engine.

Johnson, R. L.↗

NASA NTRS1989

Performance potential of air turbo-ramjet employing supersonic through-flow fan

A study was conducted to assess the performance potential of a supersonic through-flow fan in an advanced engine designed to power a Mach-5 cruise vehicle. It included a preliminary evaluation of fan performance requirements and the desirability of supersonic versus subsonic combustion, the design and performance of supersonic fans, and the conceptual design of a single-pass air-turbo-rocket/ramjet engine for a Mach 5 cruise vehicle. The study results showed that such an engine could provide high thrust over the entire speed range from sea-level takeoff to Mach 5 cruise, especially over the transonic speed range, and high fuel specific impulse at the Mach 5 cruise condition, with the fan windmilling.

Kepler, C. E.↗

NASA NTRS1988

Liquid rocket booster study. Volume 2, book 4, appendices 6-8: Reports of Rocketdyne, Pratt and Whitney, and TRW

For the pressure fed engines, detailed trade studies were conducted defining engine features such as thrust vector control methods, thrust chamber construction, etc. This was followed by engine design layouts and booster propulsion configuration layouts. For the pump fed engines parametric performance and weight data was generated for both O2/H2 and O2/RP-1 engines. Subsequent studies resulted in the selection of both LOX/RP-1 and O2/H2 propellants for the pump fed engines. More detailed analysis of the selected LOX/RP-1 and O2/H2 engines was conducted during the final phase of the study.

Source record↗

NASA NTRS1991

Designing Applications For Fasteners

"Fastener Design Manual", written to provide design engineers with single source assisting in choosing appropriate fasteners for their designs. Gives practical information on selection of fastener materials, platings, lubricants, galvanic corrosion, embrittlement by hydrogen, locking methods, inserts, washers, types and classes of threads, fatigue loading, and fastener torque.

Barrett, Richard T.↗

NASA NTRS2000

JANNAF 25th Airbreathing Propulsion Subcommittee, 37th Combustion Subcommittee and 1st Modeling and Simulation Subcommittee Joint Meeting

Volume I, the first of three volumes, is a compilation of 24 unclassified/unlimited-distribution technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 25th Airbreathing Propulsion Subcommittee, 37th Combustion Subcommittee and 1st Modeling and Simulation Subcommittee (MSS) meeting held jointly with the 19th Propulsion Systems Hazards Subcommittee. The meeting was held 13-17 November 2000 at the Naval Postgraduate School and Hyatt Regency Hotel, Monterey, California. Topics covered include: a Keynote Address on Future Combat Systems, a review of the new JANNAF Modeling and Simulation Subcommittee, and technical papers on Hyper-X propulsion development and verification; GTX airbreathing launch vehicles; Hypersonic technology development, including program overviews, fuels for advanced propulsion, ramjet and scramjet research, hypersonic test medium effects; and RBCC engine design and performance, and PDE and UCAV advanced and combined cycle engine technologies.

Fry, Ronald S.↗