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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2015

Turbo-Brayton Power Converter

Future NASA space missions will require advanced thermal-to-electric power converters that are reliable, efficient, and lightweight. Creare, LLC, is developing a turbo-Brayton power converter that offers high efficiency and specific power. The converter employs gas bearings to provide maintenance free, long-life operation. Discrete components can be packaged to fit optimally with other subsystems, and the converter's continuous gas flow can communicate directly with remote heat sources and heat rejection surfaces without the need for ancillary heat-transfer components and intermediate flow loops. Creare has completed detailed analyses, trade studies, fabrication trials, and preliminary designs for the components and converter assembly. The company is fabricating and testing a breadboard converter.

Breedlove, Jeffrey↗
NASA NTRS2016

Development Status for a Combined Solid Oxide Co-Electrolyzer and Carbon Formation Reactor System for Oxygen Regeneration

A critical component in spacecraft life support loop closure is the removal of carbon dioxide (CO2, produced by the crew) from the cabin atmosphere and chemical reduction of this CO2 to recover the oxygen. In 2015, we initiated development of an oxygen recovery system for life support applications consisting of a solid oxide co-electrolyzer (SOCE) and a carbon formation reactor (CFR). The SOCE electrolyzes a combined stream of carbon dioxide (CO2) and water (H2O) gas mixtures to produce synthesis gas (e.g., CO and H2 gas) and pure dry oxygen as separate products. This SOCE is being developed from a NASA GRC solid oxide fuel cell and stack design originally developed for aeronautics long-duration power applications. The CFR, being developed by pHMatter LLC, takes the CO and H2 output from the SOCE, and converts it primarily to solid carbon (C(s)) and H2O and CO2. Although the solid carbon accumulates in the CFR, the innovative design allows easy removal of the carbon product, requiring minimal crew member (CM) time and low resupply mass (1.0 kg/year/CM) for replacement of the solid carbon catalyst, a significant improvement over previous Bosch reactor approaches. In this work, we will provide a status of our Phase I efforts in the development and testing of both the SOCE and CFR prototype units, along with an initial assessment of the combined SOCE-CFR system, including a mass and power projections, along with an estimate of the oxygen recovery rate.

air revitalization↗
NASA NTRS2008

Review, Selection and Installation of a Rapid Prototype Machine

The objective of this paper is to impress upon the reader the benefits and advantages of investing in rapid prototyping (additive manufacturing) technology thru the procurement of one or two new rapid prototyping machines and the creation of a new Prototype and Model Lab at the Kennedy Space Center (KSC). This new resource will be available to all of United Space Alliance, LLC (USA), enabling engineers from around the company to pursue a more effective means of communication and design with our co-workers, and our customer, the National Aeronautics and Space Administration (NASA). The Rapid Protoyping/3D printing industry mirrors the transition the CAD industry made several years ago, when companies were trying to justify the expenditure of converting to a 3D based system from a 2D based system. The advantages of using a 3D system seemed to be outweighed by the cost it would take to convert not only legacy 2D drawings into 3D models but the training of personnel to use the 3D CAD software. But the reality was that when a 3D CAD system is employed, it gives engineers a much greater ability to conceive new designs and the ability to engineer new tools and products much more effectively. Rapid Prototyping (RP) is the name given to a host of related technologies that are used to fabricate physical objects directly from Computer Aided Design (CAD) data sources. These methods are generally similar to each other in that they add and bond materials in a layer wise-fashion to form objects, instead of machining away material. The machines used in Rapid Prototyping are also sometimes referred to as Rapid Manufacturing machines due to the fact that some of the parts fabricated in a RP machine can be used as the finished product. The name "Rapid Prototyping" is really a misnomer. It is much more than prototypes and it is not always rapid.

McEndree, Caryl↗
NASA NTRS2011

Power-Combined GaN Amplifier with 2.28-W Output Power at 87 GHz

Future remote sensing instruments will require focal plane spectrometer arrays with higher resolution at high frequencies. One of the major components of spectrometers are the local oscillator (LO) signal sources that are used to drive mixers to down-convert received radio-frequency (RF) signals to intermediate frequencies (IFs) for analysis. By advancing LO technology through increasing output power and efficiency, and reducing component size, these advances will improve performance and simplify architecture of spectrometer array systems. W-band power amplifiers (PAs) are an essential element of current frequency-multiplied submillimeter-wave LO signal sources. This work utilizes GaN monolithic millimeter-wave integrated circuit (MMIC) PAs developed from a new HRL Laboratories LLC 0.15- m gate length GaN semiconductor transistor. By additionally waveguide power combining PA MMIC modules, the researchers here target the highest output power performance and efficiency in the smallest volume achievable for W-band.

Fung, King Man↗
NASA NTRS1998

Intestinal transport of gentamicin with a novel, glycosteroid drug transport agent

PURPOSE: The objective was to investigate the ability of a glycosteroid (TC002) to increase the oral bioavailability of gentamicin. METHODS: Admixtures of gentamicin and TC002 were administered to the rat ileum by injection and to dogs by ileal or jejunal externalized ports, or PO. Bioavailability of gentamicin was determined by HPLC. 3H-TC002 was injected via externalized cannulas into rat ileum or jejunum, or PO and its distribution and elimination was determined. The metabolism of TC002 in rats was evaluated by solid phase extraction and HPLC analysis of plasma, urine and feces following oral or intestinal administration. RESULTS: The bioavailability of gentamicin was substantially increased in the presence of TC002 in both rats and dogs. The level of absorption was dependent on the concentration of TC002 and site of administration. Greatest absorption occurred following ileal orjejunal administration. TC002 was significantly more efficacious than sodium taurocholate, but similar in cytotoxicity. TC002 remained primarily in the GI tract following oral or intestinal administration and cleared rapidly from the body. It was only partly metabolized in the GI tract, but was rapidly and completely converted to its metabolite in plasma and urine. CONCLUSIONS: TC002 shows promise as a new drug transport agent for promoting intestinal absorption of polar molecules such as gentamicin.

Non-NASA Center↗