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Results for “designed experiment”

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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At least 343 records · Page 19
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

ERTS-C (Landsat 3) cryogenic heat pipe experiment definition

A flight experiment designed to demonstrate current cryogenic heat pipe technology was defined and evaluated. The experiment package developed is specifically configured for flight aboard an ERTS type spacecraft. Two types of heat pipes were included as part of the experiment package: a transporter heat pipe and a thermal diode heat pipe. Each was tested in various operating modes. Performance data obtained from the experiment are applicable to the design of cryogenic systems for detector cooling, including applications where periodic high cooler temperatures are experienced as a result of cyclic energy inputs.

Brennan, P. J.↗
NASA NTRS1997

Mixing of Supersonic Streams

The Strutjet approach to Rocket Based Combined Cycle (RBCC) propulsion depends upon fuel-rich flows from the rocket nozzles and turbine exhaust products mixing with the ambient air for successful operation in the ramjet and scramjet modes. A model of the Strutjet device has been built and is undergoing test to investigate the mixing of the streams as a function of distance from the Strutjet exit plane. The modeling basis was centered on using convective Mach Number as the similarity parameter to establish correlation between subscale, cold flow tests and full scale, hot firing modes. This parameter has been used successfully to correlate supersonic shear layer growth rates. The experiment design includes hot (600 R) air as the rocket exhaust simulant and hot (760 R) carbon dioxide as the turbine exhaust gas simulant. The combination of gases and their elevated temperatures was required to achieve a convective Mach Number which matched the fall scale item design conditions. The carbon dioxide is seeded with Acetone to permit tracing of the mixing processes through Laser Induced Fluorescence (LIF) techniques. The experiment and its design will be discussed in detail. Both the rocket and turbine exhaust duct nozzles are of unique (square and rectangular) shape and the turbine exhaust e)dt intersects the rocket nozzle wall upstream of the exit. Cold flow testing with the individual nozzles has been conducted to ascertain their behavior in comparison to conventional flow theory. These data are presented.

Hawk, Clark W.↗
NASA NTRS1989

Remote sensing of foliar chemistry

Remotely sensed data are being used to estimate foliar chemical content. This paper reviews how stepwise multiple regression and deconvolution have been used to extract chemical information from foliar spectra, and concludes that both methods are useful, but neither is ideal. It is recommended that the focus of research be modeling in the long term and experimentation in the short term. Long-term research should increase our understanding of the interaction between radiation and foliar chemistry so that the focus of research can move from leaf model to canopy model to field experiment. Short-term research should aim to design experiments in which remotely sensed data are used to generate unambiguous and accurate estimates of foliar chemical content.

Curran, Paul J.↗
NASA NTRS1992

Simulation of Martian surface-atmosphere interaction in a space-simulator: Technical considerations and feasibility

The Space Simulator of the German Aerospace Research Establishment at Cologne, formerly used for testing satellites, is now, since 1987, the central unit within the research sub-program 'Comet-Simulation' (KOSI). The KOSI team has investigated physical processes relevant to comets and their surfaces. As a byproduct we gained experience in sample-handling under simulated space conditions. In broadening the scope of the research activities of the DLR Institute of Space Simulation an extension to 'Laboratory-Planetology' is planned. Following the KOSI-experiments a Mars Surface-Simulation with realistic minerals and surface soil in a suited environment (temperature, pressure, and CO2-atmosphere) is foreseen as the next step. Here, our main interest is centered on thermophysical properties of the Martian surface and energy transport (and related gas transport) through the surface. These laboratory simulation activities can be related to space missions as typical pre-mission and during-the-mission support of the experiments design and operations (simulation in parallel). Post mission experiments for confirmation and interpretation of results are of great value. The physical dimensions of the Space Simulator (cylinder of about 2.5 m diameter and 5 m length) allows for testing and qualification of experimental hardware under realistic Martian conditions.

Moehlmann, D.↗
NASA NTRS1996

Factorial Design: An Eight Factor Experiment Using Paper Helicopters

The goal of this paper is to present the analysis of the multi-factor experiment (factorial design) conducted in EG490, Junior Design at Loyola College in Maryland. The discussion of this paper concludes the experimental analysis and ties the individual class papers together.

Kozma, Michael↗
NASA NTRS1998

Investigation of Springback Associated with Composite Material Component Fabrication (MSFC Center Director's Discretionary Fund Final Report, Project 94-09)

The objective of this research project was to examine processing and design parameters in the fabrication of composite components to obtain a better understanding and attempt to minimize springback associated with composite materials. To accomplish this, both processing and design parameters were included in a Taguchi-designed experiment. Composite angled panels were fabricated, by hand layup techniques, and the fabricated panels were inspected for springback effects. This experiment yielded several significant results. The confirmation experiment validated the reproducibility of the factorial effects, error recognized, and experiment as reliable. The material used in the design of tooling needs to be a major consideration when fabricating composite components, as expected. The factors dealing with resin flow, however, raise several potentially serious material and design questions. These questions must be dealt with up front in order to minimize springback: viscosity of the resin, vacuum bagging of the part for cure, and the curing method selected. These factors directly affect design, material selection, and processing methods.

Benzie, M. A.↗
NASA NTRS2010

An Investigation of Large Tilt-Rotor Short-Term Attitude Response Handling Qualities Requirements in Hover

A piloted simulation investigation was conducted using the NASA Ames Vertical Motion Simulator to study the impact of pitch, roll and yaw attitude bandwidth and phase delay on handling qualities of large tilt-rotor aircraft. Multiple bandwidth and phase delay pairs were investigated for each axis. The simulation also investigated the effect that the pilot offset from the center of gravity has on handling qualities. While pilot offset does not change the dynamics of the vehicle, it does affect the proprioceptive and visual cues and it can have an impact on handling qualities. The experiment concentrated on two primary evaluation tasks: a precision hover task and a simple hover pedal turn. Six pilots flew over 1400 data runs with evaluation comments and objective performance data recorded. The paper will describe the experiment design and methodology, discuss the results of the experiment and summarize the findings.

Malcipa, Carlos↗
NASA NTRS1988

Hypersonic drone design: A multidisciplinary experience

Efforts were focused on design problems of an unmanned hypersonic vehicle. It is felt that a scaled hypersonic drone is necessary to bridge the gap between present theory on hypersonics and the future reality of the National Aerospace Plane (NASP) for two reasons: to fulfill a need for experimental data in the hypersonic regime, and to provide a testbed for the scramjet engine which is to be the primary mode of propulsion for the NASP. Three areas of great concern to NASP design were examined: propulsion, thermal management, and flight systems. Problem solving in these areas was directed towards design of the drone with the idea that the same design techniques could be applied to the NASP. A seventy degree swept double delta wing configuration, developed in the 70's at NASA Langley, was chosen as the aerodynamic and geometric model for the drone. This vehicle would be air-launched from a B-1 at Mach 0.8 and 48,000 feet, rocket boosted by two internal engines to Mach 10 and 100,000 feet, and allowed to cruise under power of the scramjet engine until burnout. It would then return to base for an unpowered landing. Preliminary energy calculations based upon the flight requirements give the drone a gross launch weight of 134,000 lb. and an overall length of 85 feet.

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NASA NTRS1991

Shuttle Orbiter Active Thermal Control Subsystem design and flight experience

The paper examines the design of the Space Shuttle Orbiter Active Thermal Control Subsystem (ATCS) constructed for providing the vehicle and payload cooling during all phases of a mission and during ground turnaround operations. The operation of the Shuttle ATCS and some of the problems encountered during the first 39 flights of the Shuttle program are described, with special attention given to the major problems encountered with the degradation of the Freon flow rate on the Orbiter Columbia, the Flash Evaporator Subsystem mission anomalies which occurred on STS-26 and STS-34, and problems encountered with the Ammonia Boiler Subsystem. The causes and the resolutions of these problems are discussed.

Bond, Timothy A.↗
NASA NTRS1988

Hypersonic drone vehicle design: A multidisciplinary experience

UCLA's Advanced Aeronautic Design group focussed their efforts on design problems of an unmanned hypersonic vehicle. It is felt that a scaled hypersonic drone is necesary to bridge the gap between present theory on hypersonics and the future reality of the National Aerospace Plane (NASP) for two reasons: (1) to fulfill a need for experimental data in the hypersonic regime, and (2) to provide a testbed for the scramjet engine which is to be the primary mode of propulsion for the NASP. The group concentrated on three areas of great concern to NASP design: propulsion, thermal management, and flight systems. Problem solving in these areas was directed toward design of the drone with the idea that the same design techniques could be applied to the NASP. A 70 deg swept double-delta wing configuration, developed in the 70's at the NASA Langley, was chosen as the aerodynamic and geometric model for the drone. This vehicle would be air launched from a B-1 at Mach 0.8 and 48,000 feet, rocket boosted by two internal engines to Mach 10 and 100,000 feet, and allowed to cruise under power of the scramjet engine until burnout. It would then return to base for an unpowered landing. Preliminary energy calculations based on flight requirements give the drone a gross launch weight of 134,000 pounds and an overall length of 85 feet.

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NASA NTRS1995

G301: The Flying Falcon geological remote sensing experiment

Get-Away Special (GAS) G-301, named the Flying Falcon and scheduled for launch on the STS-77 Space Shuttle in April, 1996, is being prepared to perform an experiment designed by the Department of Geology, Bowling Green State University (BGSU). The experiment will employ a new type of infrared imager designed and built by a consortium of Teltron Technologies Inc., Hudson Research Inc., and BGSU that is an uncooled, quantrum ferro-electric, infrared return beam vidicon (IRBV) camera capable of detecting thermal infrared radiation throughout the 2.0-50.0 micron wavelength region, and to which an integral, unable Fabry-Perot filter and a telescopic lens have been added. The primary objectives in the experiment include the mapping of methane plumes from solid waste landfills and wetlands in the midwestern U.S., the mapping of methane plumes offshore in the Gulf of Mexico and in the Middle East, brief monitoring for precursors of volcanoes or earthquakes in the South China sea and the East Pacific Rise (about 300 km west of Easter Island), and the mapping of silica content in exposed outcrops and residual soils of the southwestern U.S. and Middle East.

Vincent, Robert K.↗
NASA NTRS1971

Study of precise positioning at L-band using communications satellites

The L-band positioning experiment is reported which encompassed experiment design, experimentation, and data reduction and analysis. In the experiment the ATS-5 synchronous satellite L-band transponder was used in conjunction with the modified ALPHA 2 navigation receivers to demonstrate the technical capability of precision position fixing for oceanographic purposes. The feasibility of using relative ranging techniques implemented by two identical receiving systems, properly calibrated, to determine a line of position accurately on the surface of the earth was shown. The program demonstrated the level of resolution, repeatibility, precision, and accuracy of existing modest-cost effective navigation equipment. The experiment configuration and data reduction techniques were developed in parallel with the hardware modification tasks. Test results verify the ability of a satellite-based system to satisfy the requirements of precision position fixing.

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NASA NTRS1987

Atmospheric surface and boundary layers of the Amazon Basin

Three phases of work were performed: design of and preparation for the Amazon Boundary Layer Experiment (ABLE 2-A); execution of the ABLE 2-A field program; and analysis of the ABLE 2-A data. Three areas of experiment design were dealt with: surface based meteorological measurements; aircraft missions; and project meteorological support. The primary goal was to obtain a good description of the structure of the atmosphere immediately above the rain forest canopy (top of canopy to a few thousand meters), to describe this region during the growing daytime phase of the boundary layer; and to examine the nighttime stratified state. A secondary objective was to examine the role that deep convective storms play in the vertical transport of heat, water vapor, and other trace gases. While significant progress was made, much of the analysis remains to be done.

Garstang, Michael↗
NASA NTRS2015

2D Electrostatic Actuation of Microshutter Arrays

An electrostatically actuated microshutter array consisting of rotational microshutters (shutters that rotate about a torsion bar) were designed and fabricated through the use of models and experiments. Design iterations focused on minimizing the torsional stiffness of the microshutters, while maintaining their structural integrity. Mechanical and electromechanical test systems were constructed to measure the static and dynamic behavior of the microshutters. The torsional stiffness was reduced by a factor of four over initial designs without sacrificing durability. Analysis of the resonant behavior of the microshutter arrays demonstrates that the first resonant mode is a torsional mode occurring around 3000 Hz. At low vacuum pressures, this resonant mode can be used to significantly reduce the drive voltage necessary for actuation requiring as little as 25V. 2D electrostatic latching and addressing was demonstrated using both a resonant and pulsed addressing scheme.

Multiobject Imaging↗
NASA NTRS2015

2D Electrostatic Actuation of Microshutter Arrays

Electrostatically actuated microshutter arrays consisting of rotational microshutters (shutters that rotate about a torsion bar) were designed and fabricated through the use of models and experiments. Design iterations focused on minimizing the torsional stiffness of the microshutters, while maintaining their structural integrity. Mechanical and electromechanical test systems were constructed to measure the static and dynamic behavior of the microshutters. The torsional stiffness was reduced by a factor of four over initial designs without sacrificing durability. Analysis of the resonant behavior of the microshutters demonstrates that the first resonant mode is a torsional mode occurring around 3000 Hz. At low vacuum pressures, this resonant mode can be used to significantly reduce the drive voltage necessary for actuation requiring as little as 25V. 2D electrostatic latching and addressing was demonstrated using both a resonant and pulsed addressing scheme.

Multiobject Imaging↗
NASA NTRS1988

Design of an expert system for estimating the cost of new knowledge in high energy astrophysics

The High Energy Astrophysics Costing Tool (HEACT) is a combined Expert System/Numerical Simulation to evaluate sensors and experiments proposed for space platforms in order to determine their expected performance and to assess the amount and quality of scientific information likely to be gathered by such experiments. The end product of this tool will be both a cost estimate for the experiment package as deployed and also an estimate of the amount of new scientific knowledge (both new data and reductions in the uncertainties of previous measurements) which would result from the actual deployment and operation of that experiment package. The numerical simulation part of HEACT will contain components to: (1) calculate the high energy signatures of both actual and proposed classes of astrophysical objects, and (2) model the response and resolution of the candidate sensors for observing those objects. The rule based part of the HEACT will be based on knowledge in the areas of experiment design, instrument selection, and system integration developed from experience with existing high energy astrophysics observatories, both orbiting and lofted by rockets or balloons. This paper presents mainly results from the design of the rule-based part of HEACT. It focuses on the structure of the rules and the structures used to represent the knowledge related to the design and integration of such experiments. Methods for integrating the results from numerical simulations into the expert system will also be discussed.

Bosworth, Edward L., Jr.↗
NASA NTRS1978

Vestibular Function Research (VFR) experiment. Phase B: Design definition study

The Vestibular Functions Research (VFR) Experiment was established to investigate the neurosensory and related physiological processes believed to be associated with the space flight nausea syndrome and to develop logical means for its prediction, prevention and treatment. The VFR Project consists of ground and spaceflight experimentation using frogs as specimens. The phase B Preliminary Design Study provided for the preliminary design of the experiment hardware, preparation of performance and hardware specification and a Phase C/D development plan, establishment of STS (Space Transportation System) interfaces and mission operations, and the study of a variety of hardware, experiment and mission options. The study consist of three major tasks: (1) mission mode trade-off; (2) conceptual design; and (3) preliminary design.

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