Fuels and Energy Sources

Hydrogen fuel

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Briefs: Physical Sciences
Since its invention in 1948, the transistor has revolutionized everyday life. The electronics revolution is based on miniaturization of transistors; smaller transistors are faster, and...
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Briefs: Physical Sciences
DNS of a Supercritical H₂/O₂ Mixing Layer
This report discusses direct numerical simulations (DNS) of a mixing layer between supercritical flows of oxygen and hydrogen. The governing conservation equations were those of fluctuation- dissipation (FD) theory, in which low-pressure typical transport properties (viscosity, diffusivity and thermal...
Briefs: Mechanical & Fluid Systems
Ice-Melting Probe Using Steam and Jets of Hot Water
An improved probe has been proposed for burrowing vertically into ice for scientific exploration of polar icecaps, glaciers, and the like. The predecessor of the improved probe is a Philbert probe, which contains an electric heater to melt the ice in contact with it and thereby make it descend...
Briefs: Electronics & Computers
High-Capacity Nickel-Hydrogen Cells
Nickel-hydrogen electrochemical cells with capacities of 350 ampere-hours have been developed. These cells are intended primarily for use in government and commercial satellites; they have been fully qualified to satisfy performance requirements for operation in geosynchronous satellites for as long as 15 years....
Briefs: Physical Sciences
The Propulsion group at Dryden Flight Research Center is performing analyses of the effectiveness of chemical-species sensors for detecting and assessing leakage. The group is also...
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Briefs: Physical Sciences
Molten-Carbonate Electrolyzers for Making CO and O2
Electrochemical cells in which molten carbonates would serve as electrolytes have been proposed for use in electrolyzing CO2. The proposal was made in an effort to implement a concept of in situ resource utilization (ISRU) for the exploration of Mars; the basic idea is to generate CO (if needed as...
Briefs: Mechanical & Fluid Systems
Miniature Electrothermal Thruster
A report proposes a miniature electrothermal spacecraft engine. The engine would include a chamber with an inside length of ≈1.5 cm and inside diameter of ≈0.25 cm, with a dielectric (ideally diamond) sidewall lining, a metal-coated expansion nozzle at one end, and a metal electrode at the other end. A...
Briefs: Mechanical & Fluid Systems
Variable-Specific-Impulse Magnetoplasma Rocket
Johnson Space Center has been leading the development of a high-power, electrothermal plasma rocket — the variable- specific-impulse magnetoplasma rocket (VASIMR) — that is capable of exhaust modulation at constant power. An electrodeless design enables the rocket to operate at power densities much...
Briefs: Medical
Spacecraft-Facility Microbes Tolerate H2O2, NaCl, and Heat
A report describes experiments that were performed to isolate and characterize microbes that survive conditions of controlled circulation of air, desiccation, low nutrient concentrations, and moderately high temperatures in a spacecraft-assembly facility. These conditions are more severe...
Briefs: Mechanical & Fluid Systems
A proposal has been made to develop bimorph actuators and force sensors based on carbon nanotubes. The proposed devices could make it possible to generate, sense, and control displacements and...
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Briefs: Physical Sciences
A portable apparatus that operates at atmospheric pressure generates a beam of monatomic oxygen. The apparatus is designed to be used in a dry, noncontact process for removing organic...
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Briefs: Test & Measurement
A Mass-Spectrometer System for Detecting Gas Leaks
The Hydrogen Umbilical Mass Spectrometer (HUMS) consists of an integrated sample delivery system, a commercial mass-spectrometer- based gas analyzer, and a set of calibration gas mixtures traceable to NIST (National Institute for Standards and Technology). The system, except for the calibration gas...
Briefs: Test & Measurement
A Mass-Spectrometer System for Detecting Gas Leaks
The Hydrogen Umbilical Mass Spectrometer (HUMS) consists of an integrated sample delivery system, a commercial mass-spectrometer-based gas analyzer, and a set of calibration gas mixtures traceable to NIST (National Institute for Standards and Technology). The system, except for the calibration gas...
Briefs: Materials
Metal-supported catalyst beds with improved thermal and flow characteristics for promoting endothermic chemical reactions are undergoing development. In the proposed original application,...
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Briefs: Physical Sciences
A hand-held instrument that contains two silicon-based charge-coupled-device (CCD) video cameras (see figure) has been developed for imaging hydrogen fires. This or a similar instrument is needed...
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Briefs: Materials
Corrosion of iron and steel substrates can be inhibited by coating them with any of the wide variety of compounds denoted generally as polyanilines. A polyaniline suitable for this type of...
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Briefs: Test & Measurement
An apparatus measures small concentrations of H2, O2, and H2O in flowing He gas. In the original application for which the apparatus was developed, the flow of He gas is used to purge a...
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Briefs: Physical Sciences
A new concept called "liquid shell insulation" has been proposed as a means of temporary thermal protection for scientific instrument probes that are required to operate for short times in hot, high-pressure...
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Briefs: Physical Sciences
NASA Dryden Flight Research Center has ruggedized and qualified an inexpensive commercial off-the-shelf (COTS) oxygen sensor that accurately and reliably aids assessment, in flight...
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Briefs: Mechanical & Fluid Systems
Vortex-Fired Liquid-Fuel Rocket Combustion Chambers
Liquid-fuel rocket engines that utilize vortex flow fields to keep combustion-chamber walls cool have been investigated in computational simulations and experiments. In an engine of this type, the vortex flow establishes radial gradients of pressure and density that cause the lower-density hot...
Briefs: Materials
A program of research and development is addressing the feasibility of using magnetoplasmadynamic (MPD) sources in the chemical vapor deposition (CVD) of synthetic diamond films. Because of its...
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Briefs: Physical Sciences
The presence of corrosives in the Earth's atmosphere is of global concern. From acid rains that are destroying forests and disfiguring monuments like the Parthenon and the pyramids, to atmospheric pollutants that produce...
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Briefs: Physical Sciences
Detecting Metal Ions by Voltammetry Using Diamond Electrodes
Experiments have demonstrated the feasibility of detecting multiple species of toxic metal ions and other ions of interest dissolved in water, by means of voltammetry with electrically conductive artificial diamond electrodes. Diamond is attractive as an electrode material because it is...
Briefs: Robotics, Automation & Control
An improved system for densifying (by cooling) the liquid hydrogen and liquid oxygen used as propellants for the space shuttle has been proposed. These propellant liquids are cooled...
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Briefs: Electronics & Computers
Improved Control of Charging Current for Ni/H Battery
In a proposed method of controlling the electric current supplied for charging a nickel/hydrogen battery, the rate of evolution of heat would be taken into account along with the electrical quantities (voltage, current, and/or charge as functions of time) that are traditionally taken into...
Briefs: Photonics/Optics
A special-purpose multispectral video camera has been designed to provide an enhanced capability for viewing hydrogen fires. Hydrogen fires do not emit sufficient visible light to be seen...
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Briefs: Energy
Studies of physical and chemical effects in the hydride-forming electrodes of rechargeable nickel/metal hydride electrochemical cells have yielded results that now guide...
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Briefs: Physical Sciences
An effective Lewis number has been defined for two-fluid mixtures under conditions of (1) supercritical temperature and pressure and (2) large gradients of temperature and composition. The Lewis...
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Briefs: Physical Sciences
A mathematical model has been developed to predict the behavior of mutually interacting drops of a first fluid surrounded by a second fluid, under quiescent conditions at...
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