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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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Engineering the LISA Project: Systems Engineering Challenges
The Laser Interferometer Space Antenna (LISA) is a joint NASA/ESA mission to detect and measure gravitational waves with periods from 1 s to 10000 s. The systems engineering challenges of developing a giant interferometer, 5 million kilometers on a side, an: numerous. Some of the key challenges are presented in this paper. The organizational challenges imposed by sharing the engineering function between three centers (ESA ESTEC, NASA GSFC, and JPL) across nine time zones are addressed. The issues and approaches to allocation of the acceleration noise and measurement sensitivity budget terms across a traditionally decomposed system are discussed. Additionally, using LISA to detect gravitational waves for the first time presents significant data analysis challenges, many of which drive the project system design. The approach to understanding the implications of science data analysis on the system is also addressed.
Light‐driven catalysis with engineered enzymes and biomimetic systems
Abstract Efforts to drive catalytic reactions with light, inspired by natural processes like photosynthesis, have a long history and have seen significant recent growth. Successfully engineering systems using biomolecular and bioinspired catalysts to carry out light‐driven chemical reactions capitalizes on advantages offered from the fields of biocatalysis and photocatalysis. In particular, driving reactions under mild conditions and in water, in which enzymes are operative, using sunlight as a renewable energy source yield environmentally friendly systems. Furthermore, using enzymes and bioinspired systems can take advantage of the high efficiency and specificity of biocatalysts. There are many challenges to overcome to fully capitalize on the potential of light‐driven biocatalysis. In this mini‐review, we discuss examples of enzymes and engineered biomolecular catalysts that are activated via electron transfer from a photosensitizer in a photocatalytic system. We place an emphasis on selected forefront chemical reactions of high interest, including CH oxidation, proton reduction, water oxidation, CO 2 reduction, and N 2 reduction.
Portable bacterial CRISPR transcriptional activation enables metabolic engineering in Pseudomonas putida
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Engineering the cellulolytic bacterium, Clostridium thermocellum, to co-utilize hemicellulose
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Data for "Metabolic Engineering Strategies to Produce Medium-Chain Oleochemicals via Acyl-ACP:CoA Transacylase Activity"
Microbial lipid metabolism is an attractive route for producing oleochemicals. The predominant strategy centers on heterologous thioesterases to synthesize desired chain-length fatty acids. To convert acids to oleochemicals (e.g., fatty alcohols, ketones), the narrowed fatty acid pool needs to be reactivated as coenzyme A thioesters at cost of one ATP per reactivation – an expense that could be saved if the acyl-chain was directly transferred from ACP- to CoA-thioester. Here, we demonstrate such an alternative acyl-transferase strategy by heterologous expression of PhaG, an enzyme first identified in Pseudomonads, that transfers 3-hydroxy acyl-chains between acyl-carrier protein and coenzyme A thioester forms for creating polyhydroxyalkanoate monomers. We use it to create a pool of acyl-CoA’s that can be redirected to oleochemical products. Through bioprospecting, mutagenesis, and metabolic engineering, we develop three strains of Escherichia coli capable of producing over 1 g/L of medium-chain free fatty acids, fatty alcohols, and methyl ketones.
Engine-integrated secondary injection side- force generation for the hydrogen-fueled rocket engine
Engine-integrated secondary injection side-force generation for hydrogen-fueled rocket engine
High-lift characteristics of a variable-sweep supersonic transport model with a blended engine-fuselage and engine-mounted horizontal tails
High lift characteristics of variable-sweep transport model with blended engine-fuselage and engine-mounted horizontal tails
Low-speed characteristics of a variable-sweep supersonic transport model with a blended engine fuselage and engine-mounted tails
Low-speed characteristics of variable-sweep supersonic transport model with blended engine fuselage and engine-mounted tails
Two surveys of the needs of engineering schools in the field of biomechanical and human factors engineering education
Surveys of engineering school needs in field of biomechanical and human factors engineering education
Engine restart and thermodynamic analysis of Apollo spacecraft engine tests, volume 2
Cold flow and hot firing test details for Apollo spacecraft ascent, descent, and service propulsion system engines to define hypergol engine restart limits
Summary of fluid mechanics and engine characteristics research on the nuclear light bulb engine concept
Fluid mechanics and engine dynamics and start-up experiments simulating thermal environment in nuclear light bulb engine
Coupled supersonic inlet-engine control using overboard bypass doors and engine speed to control normal shock position
Coupled supersonic inlet-engine control using overboard bypass doors and engine speed to control normal shock position
Practical engineering methods for predicting hot gas reingestion characteristics of V/STOL aircraft jet lift engines
Engineering methods for predicting temperatures and velocities in vicinity of vertical lift engines of jet V/STOL aircraft operating near ground
A supersonic inlet-engine control using engine speed as a primary variable for controlling normal shock position
Supersonic inlet engine control using engine speed as primary variable for controlling normal shock position
Experimental quiet engine program. Volume 1, phase 1 - Engine design report
Turbofan engine designs and tests for engine noise reduction
Experimental quiet engine program. Volume 2, phase 1 - Engine design report
Low pressure turbofan rotor, stator, frame, and exhaust nozzle designs for turbofan engine noise reduction including acoustics and engine tests
The open-cycle gas-core nuclear rocket engine - Some engineering considerations.
A preliminary design study of a conceptual 6000-MW open-cycle gas-core nuclear rocket engine system was made. The engine has a thrust of 44,200 lb and a specific impulse of 4400 sec. The nuclear fuel is uranium-235 and the propellant is hydrogen. Critical fuel mass was calculated for several reactor configurations. Major components of the reactor (reflector, pressure vessel) and the waste heat rejection system were considered conceptually and were sized.