Vehicles and Performance

Aerodynamics

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Briefs: Software
Predicting Accumulations of Ice on Aerodynamic Surfaces
LEWICE is a computer program that predicts the accumulation of ice on two-dimensional aerodynamic surfaces under conditions representative of the flight of an aircraft through an icing cloud. The software first calculates the airflow surrounding the body of interest, then uses the airflow to...
Briefs: Electronics & Computers
An apparatus that is extremely effective in dispensing a wide range of droplets has been developed. This droplet dispenser is unique in that it utilizes a droplet bias voltage, as well as an ionization pulse, to...
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Briefs: Mechanical & Fluid Systems
Three techniques have been proposed to prolong the intervals of time available for microgravity experiments aboard airplanes flown along parabolic trajectories. Typically, a pilot strives to...
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Briefs: Physical Sciences
Update on Area Production in Mixing of Supercritical Fluids
The paper “Turbulence and Area Production in Binary-Species, Super- critical Transitional Mixing Layers” presents a more recent account of the research sum- marized at an earlier stage in “Area Production in Super- critical, Transitional Mixing Layers” (NPO-30425), NASA Tech...
Briefs: Materials
Scandia-and-Yttria-Stabilized Zirconia for Thermal Barriers
Zirconia stabilized with both scandia and yttria in suitable proportions has shown promise of being a superior thermal-barrier coating (TBC) material, relative to zirconia stabilized with yttria only. More specifically, a range of compositions in the zirconia/scandia/yttria material system...
Briefs: Motion Control
Two apparatuses now under development are intended to perform a variety of deep-drilling, coring, and sensing functions for subsurface exploration of rock and soil. These are modified versions...
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Briefs: Mechanical & Fluid Systems
Engineers at NASA's Dryden Flight Research Center have received a patent on an emergency flight-control method implemented by a propulsion-controlled aircraft (PCA) system. Utilizing the...
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Briefs: Mechanical & Fluid Systems
Extension of Liouville Formalism to Postinstability Dynamics
A mathematical formalism has been developed for predicting the postinstability motions of a dynamic system governed by a system of nonlinear equations and subject to initial conditions. Previously, there was no general method for prediction and mathematical modeling of postinstability...
Briefs: Materials
Antistatic Polycarbonate/Copper Oxide Composite
A composite material consisting of polycarbonate filled with copper oxide has been found to be suitable as an antistatic material. This material was developed to satisfy a requirement for an antistatic material that has a mass density less than that of aluminum and that exhibits an acceptably low...
Briefs: Mechanical & Fluid Systems
Booms and other structures consisting mainly of thin spring strips are undergoing development. These structures are designed to be lightweight, to be compactly stowable, and to be capable of springing to...
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Briefs: Mechanical & Fluid Systems
Brush-Wheel Samplers for Planetary Exploration
A report proposes brush-wheel mechanisms for acquiring samples of soils from remote planets. In simplest terms, such a mechanism would contain brush wheels that would be counter-rotated at relatively high speed. The mechanism would be lowered to the ground from a spacecraft or other exploratory...
Briefs: Information Technology
Software for Collaborative Engineering of Launch Rockets
The Rocket Evaluation and Cost Integration for Propulsion and Engineering software enables collaborative computing with automated exchange of information in the design and analysis of launch rockets and other complex systems. RECIPE can interact with and incorporate a variety of programs,...
Briefs: Materials
Lower-Conductivity Thermal-Barrier Coatings
Thermal-barrier coatings (TBCs) that have both initial and post-exposure thermal conductivities lower than those of yttria-stabilized zirconia TBCs have been developed. TBCs are thin ceramic layers, generally applied by plasma spraying or physical vapor deposition, that are used to insulate air-cooled...
Briefs: Mechanical & Fluid Systems
A computational study has shown that by injecting drops in jets of gas having square, elliptical, triangular, or other noncircular injection cross sections, it should be possible to...
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Briefs: Physical Sciences
Detecting Conductive Liquid Leaking From Nonconductive Pipe
A method that can be implemented with relatively simple electronic circuitry provides a capability for detecting leakage of an electrically conductive liquid from an electrically nonconductive underground pipe. Alternatively or in addition, the method can be applied to locate the pipe,...
Briefs: Physical Sciences
Turbulence in Supercritical O₂/H₂ and C₇H₁₆/N₂ Mixing Layers
This report presents a study of numerical simulations of mixing layers developing between opposing flows of paired fluids under supercritical conditions, the purpose of the study being to elucidate chemical-species- specific aspects of turbulence. The simulations were...
Briefs: Physical Sciences
An improved design has been proposed for a cryostat of a type that maintains a desired low temperature mainly through boiloff of a liquid cryogen (e.g., liquid nitrogen) at atmospheric...
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Briefs: Medical
The hydrodynamic focusing bioreactor (HFB) is a bioreactor system designed for three-dimensional cell culture and tissue-engineering investigations on orbiting spacecraft and in...
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Briefs: Information Technology
Irreversible Entropy Production in Two-Phase Mixing Layers
This report presents a study of dissipation (irreversible production of entropy) in three-dimensional, temporal mixing layers laden with evaporating liquid drops. The purpose of the study is to examine the effects of evaporating drops on the development of turbulent features in flows....
Briefs: Electronics & Computers
Eroding potentiometers have been devised for measuring the time-dependent positions of char fronts advancing through layers of insulating material subject to intense heating from one side. In the original application, the...
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Briefs: Materials
Mixed Conducting Electrodes for Better AMTEC Cells
Electrode materials that exhibit mixed conductivity (that is, both electronic and ionic conductivity) have been investigated in a continuing effort to improve the performance of the alkali metal thermal-to-electric converter (AMTEC). These electrode materials are intended primarily for use on the...
Briefs: Mechanical & Fluid Systems
NASA Dryden Flight Research Center's new Propulsion Flight Test Fixture (PFTF), designed in house, is an airborne engine-testing facility that enables engineers to gather flight data on small experimental engines....
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Briefs: Software
LabVIEW Serial Driver Software for an Electronic Load
A LabVIEW-language computer program enables monitoring and control of a Transistor Devices, Inc., Dynaload WCL232 (or equivalent) electronic load via an RS- 232 serial communication link between the electronic load and a remote personal computer. (The electronic load can operate at constant...
Briefs: Materials
Water-Borne, Silicone-Based, Primerless Paints
Water-borne, silicone- based paints for protecting metal structures against corrosion have been developed as substitutes for traditional anticorrosion paints that contain large amounts of volatile organic solvents. It is desirable to reduce the volatile-organic-compound (VOC) contents of paints in...
Briefs: Software
Software for Designing Thermal Protection for Spacecraft
Traj and Traj.CGI are computer programs for designing thermal-protection systems (TPSs) for spacecraft that must survive re-entry into planetary atmospheres. Together with a separately developed program denoted FIAT, Traj and Traj.CGI are integral parts of NASA’s Entry Vehicle Integrated...
Briefs: Mechanical & Fluid Systems
Precise Air Bearings Redesigned
Highly precise air bearings for suspending objects over an epoxy flat floor in a laboratory have been developed. These bearings float on airgaps 3 to 5 mil (about 0.08 to 0.13 mm) thick. They are modern versions of precise air bearings, developed during the 1960s, that offer a working coefficient of friction of only...
Briefs: Electronics & Computers
During development and production, cell phones and other portable devices must be tested and calibrated with a power source that accurately simulates battery...
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Briefs: Mechanical & Fluid Systems
Flight data gathered by use of the F-18 System Research Aircraft (SRA) based at Dryden Flight Research Center have been used to estimate stability and control derivatives for a baseline F-18 airplane....
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Briefs: Mechanical & Fluid Systems
Some airfoil designs have been shown by theory and small-scale tests to be capable of passively maintaining laminar flow at super -sonic speeds. More recently, flight tests have proven that these...
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