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Physical Sciences

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Briefs: Physical Sciences

This enhanced illumination design and analysis program, called LightTools® 5.1, enables easy and accurate modeling of sophisticated backlights for flat panel displays....

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Briefs: Physical Sciences
Using Laser-Induced Incandescence To Measure Soot in Exhaust

An instrumentation system exploits laser-induced incandescence (LII) to measure the concentration of soot particles in an exhaust stream from an engine, furnace, or industrial process that burns hydrocarbon fuel. In comparison with LII soot-concentration-measuring systems that have...

Briefs: Physical Sciences
Helicity in Supercritical O₂/H₂ and C₇H₁₆/N₂ Mixing Layers

This report describes a study of databases produced by direct numerical simulation of mixing layers developing between opposing flows of two fluids under supercritical conditions, the purpose of the study being to elucidate chemical species-specific aspects of turbulence,...

Briefs: Physical Sciences

A proposed toroidal or disklike dielectric optical resonator (dielectric optical cavity) would be made of an optically nonlinear material and would be optimized for use in parametric...

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Briefs: Physical Sciences

An experimental airborne remote sensing system includes a remotely controlled, lightweight, solar-powered airplane (see figure) that carries two digital-output electronic cameras and communicates...

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Briefs: Physical Sciences
Inspecting Friction Stir Welding Using Electromagnetic Probes

A report describes the use of advanced electromagnetic probes to measure the dimensions, the spatial distribution of electrical conductivity, and related other properties of friction stir welds (FSWs) between parts made of the same or different aluminum alloy(s). The probes are of the...

Briefs: Physical Sciences
Spaceborne Infrared Atmospheric Sounder

A report describes the development of the spaceborne infrared atmospheric sounder (SIRAS)—a spectral imaging instrument, suitable for observing the atmosphere of the Earth from a spacecraft, that utilizes four spectrometers to cover the wavelength range of 12 to 15.4 µm with a spectral resolution that...

Briefs: Physical Sciences
Using Redundancy To Reduce Errors in Magnetometer Readings

A method of reducing errors in noisy magnetic-field measurements involves exploitation of redundancy in the readings of multiple magnetometers in a cluster. By "redundancy" his meant that the readings are not entirely independent of each other because the relationships among...

Briefs: Physical Sciences
Position-Finding Instrument Built Around a Magnetometer

A coarse-positioning instrument is built around a three-axis magnetometer. The magnetometer is of a type that is made of inexpensive hardware and is suitable for use aboard spacecraft orbiting no more than 1,000 km above the surface of the Earth. A data processor programmed with suitable...

Briefs: Physical Sciences
Lightweight, Low-CTE Tubes Made From Biaxially Oriented LCPs

Tubes made from biaxially oriented liquid-crystal polymers (LCPs) have been developed for use as penetrations on cryogenic tanks. ("Penetrations" in this context denotes feed lines, vent lines, and sensor tubes, all of which contribute to the undesired conduction of heat into the...

Briefs: Physical Sciences

Efforts are under way to develop a nanofluidic size-exclusion chromatograph (SEC), which would be a compact, robust, lightweight instrument for separating molecules of interest according to their...

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Briefs: Physical Sciences

An improved method of measuring chromatic dispersion in an optical fiber or other device affords a lower (relative to prior such methods) limit of measurable dispersion. This method is a...

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Briefs: Physical Sciences

A proposed optoelectronic instrument would perform several different spectroscopic and imaging functions that, heretofore, have been performed by separate instruments. The functions would be...

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Briefs: Physical Sciences

Semiconductor electron-spin filters of a proposed type would be based on the Rashba effect, which is described briefly below. Electron-spin filters — more precisely, sources of...

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Briefs: Physical Sciences

A batch of experimental diffusion-cooled hot-electron bolometers (HEBs), suitable for use as mixers having input frequencies in the terahertz range and output frequencies up to about a...

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Briefs: Physical Sciences

An improved optoelectronic apparatus has been developed to provide the position feedback needed for controlling the levitation subsystem of a containerless processing system. As...

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Briefs: Physical Sciences

Optoelectronic sensors and magnetic actuators have been developed as parts of a system for controlling the relative position and attitude of two massive optical tables that float...

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Briefs: Physical Sciences
Part 2 of a Computational Study of a Drop-Laden Mixing Layer

This second of three reports on a computational study of a mixing layer laden with evaporating liquid drops presents the evaluation of Large Eddy Simulation (LES) models.

Briefs: Physical Sciences

A proposed technique for locating concealed objects (especially small antipersonnel land mines) involves the acquisition and processing of spectral signatures over broad microwave...

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Briefs: Physical Sciences

A holographic technique has been devised for generating a visible display of the effect of exposure of a photorefractive crystal to γ-rays. The technique exploits the space charge that results...

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Briefs: Physical Sciences

A digital averaging phasemeter has been built for measuring the difference between the phases of the unknown and reference heterodyne signals in a heterodyne laser interferometer....

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Briefs: Software
Preparing and Analyzing Iced Airfoils

SmaggIce version 1.2 is a computer program for preparing and analyzing iced airfoils.It includes interactive tools for

measuring ice-shape characteristics, controlled smoothing of ice shapes, curve discretization, generation of artificial ice shapes,and detection and correction of input errors.
Briefs: Physical Sciences
Working Fluids for Increasing Capacities of Heat Pipes

A theoretical and experimental investigation has shown that the capacities of heat pipes can be increased through suitable reformulation of their working fluids. The surface tensions of all of the working fluids heretofore used in heat pipes decrease with temperature. As explained in more...

Briefs: Physical Sciences

An improved method of calibrating a large directional radio antenna of the type used in deep-space communication and radio astronomy has been developed. This method involves a...

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Briefs: Physical Sciences

A modified coronagraph has been proposed as a prototype of improved notch filters in Raman spectrometers. Corona-graphic notch filters could offer alternatives to both (1) the large and...

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Briefs: Physical Sciences
Rapid Chemometric Filtering of Spectral Data

A method of rapid, programmable filtering of spectral transmittance, reflectance, or fluorescence data to measure the concentrations of chemical species has been proposed. By "programmable" is meant that a variety of spectral analyses can readily be performed and modified in software,...

Briefs: Physical Sciences
Part 1 of a Computational Study of a Drop-Laden Mixing Layer

This first of three reports on a computational study of a drop-laden temporal mixing layer presents the results of direct numerical simulations (DNS) of well-resolved flow fields and the derivation of the large-eddy simulation (LES) equations that would govern the larger scales of a...

Briefs: Physical Sciences
Selected Papers on Protoplanetary Disks
Three papers present studies of thermal balances, dynamics, and electromagnetic spectra of protoplanetary disks, which comprise gas and dust orbiting young stars. One paper addresses the reprocessing, in a disk, of photons that originate in the disk itself in addition to photons that originate in the stellar...
Briefs: Physical Sciences
Integrated-Optic Oxygen Sensors

Compact optical oxygen sensors with self-calibration capabilities are undergoing development. A sensor of this type features a single-chip, integrated-optic design implemented by photolithographic fabrication of optical waveguides in a photosensitive porous glass. The porosity serves as both a matrix for retention...

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Tech Update: 3D Printing for Transportation in 2024

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Building an Automotive EMC Test Plan

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The Moon and Beyond from a Thermal Perspective

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