223
223
Jun 2, 2011
06/11
by
Kroes, Roger L.; Reiss, Donald A.; Lehoczky, Sandor L
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eye 223
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A new method for initiating nucleation from solutions in microgravity which avoids nucleation on container walls and other surfaces is described. This method consists of injecting a small quantity of highly concentrated, heated solution into the interior of a lightly supersaturated, cooler host gowth solution. It was tested successfully on USML-I, producing a large number of LAP crystals whose longest dimension averaged 1 mm.
Topics: CYLINDRICAL SHELLS, MATHEMATICAL MODELS, GAS FLOW, FLUTTER, AERODYNAMIC FORCES, DIFFERENTIAL...
387
387
Jul 6, 2010
07/10
by
Chigier, N. A.; Corsiglia, V. R
texts
eye 387
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Data are presented on velocity measurements made with hot wire anemometers in the wake of a model of the CV-990 aircraft and a rectangular wing in the NASA-Ames 2.14x3.05 meter (7- by 10-foot) wind tunnels. Variables included angle of attack, tunnel speed and axial distance up to 12 chord lengths downstream from the wing trailing edge. Effects of deflecting trailing edge flaps and small spoiler panels are shown.
Topics: AERODYNAMIC CHARACTERISTICS, AERODYNAMIC FORCES, HELICOPTERS, ROTARY WINGS, AUTOROTATION,...
223
223
Jul 5, 2010
07/10
by
Anderson, B. H.; Bowditch, D. N
texts
eye 223
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No Abstract Available
Topics: AERODYNAMIC FORCES, HEAT TRANSFER, REENTRY VEHICLES, AERODYNAMIC CONFIGURATIONS, INDEPENDENT...
307
307
May 29, 2011
05/11
by
Reid, Michael R
texts
eye 307
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The High Level Architecture (HLA) is a current US Department of Defense and an industry (IEEE-1516) standard architecture for modeling and simulations. It provides a framework and set of functional rules and common interfaces for integrating separate and disparate simulators into a larger simulation. The goal of the HLA is to reduce software costs by facilitating the reuse of simulation components and by providing a runtime infrastructure to manage the simulations. In order to evaluate the...
Topics: AERODYNAMIC BALANCE, FORCE DISTRIBUTION, AERODYNAMIC FORCES, STABILITY DERIVATIVES, VECTOR...
227
227
Jul 12, 2010
07/10
by
NON
texts
eye 227
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comment 0
No Abstract Available
Topics: AERODYNAMIC BALANCE, ERROR ANALYSIS, SPIN STABILIZATION, VACUUM, AERODYNAMIC FORCES, INTELSAT...
428
428
Jun 9, 2011
06/11
by
Wang, Qun-Zhen; Massey, Steven J.; Abdol-Hamid, Khaled S.; Frink, Neal T
texts
eye 428
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USM3D is a widely-used unstructured flow solver for simulating inviscid and viscous flows over complex geometries. The current version (version 5.0) of USM3D, however, does not have advanced turbulence models to accurately simulate complicated flows. We have implemented two modified versions of the original Jones and Launder k-epsilon two-equation turbulence model and the Girimaji algebraic Reynolds stress model in USM3D. Tests have been conducted for two flat plate boundary layer cases, a...
Topics: COMPUTATIONAL FLUID DYNAMICS, DATA BASES, NONLINEARITY, AERODYNAMIC FORCES, WIND TUNNELS, STEADY...
415
415
Jul 23, 2010
07/10
by
Hashimoto, R.; Nagamatsu, A.; Michimura, S
texts
eye 415
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The vibration of the rotating disk is analyzed using the finite element method with consideration given to the effect of centrifugal force. A fan-shaped element is proposed for the first time for the analysis of both in-plane and bending deformations of the shell structure. The calculated results of the natural modes and frequencies of a model disk are compared with the experimental results with good quantitative agreement. .
Topics: AERODYNAMIC FORCES, ALGORITHMS, MATHEMATICAL MODELS, REGRESSION ANALYSIS, STABILITY DERIVATIVES,...
276
276
May 6, 2010
05/10
by
Mac Neal, R.; Schuerch, H. U
texts
eye 276
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Centrifugally stabilized structure for atmospheric entry from space - aerodynamic forces on rotor blade element developed using newtonian momentum concept
Topics: AERODYNAMIC FORCES, ATMOSPHERIC ENTRY, MOMENTUM, REENTRY PHYSICS, ROTOR AERODYNAMICS, ATMOSPHERIC...
358
358
texts
eye 358
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The author has identified the following significant results. A time series of the Loop Current in the Gulf of Mexico, covering an annual cycle of growth, spreading, and decay, has been obtained in synchronization with ERTS-1. Computer enhanced images, which are necessary to extract useful oceanic information, show that the current can be observed either by color or sea state effects associated with the cyclonic boundary. The color effect relates to the spectral variations in the optical...
Topics: AIRCRAFT LANDING, AIRCRAFT PERFORMANCE, COMPUTER PROGRAMS, PERFORMANCE PREDICTION, TAKEOFF,...
225
225
May 29, 2011
05/11
by
Maks, Lori; Breed, Julie; Rackley, Michae
texts
eye 225
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NASA is particularly concerned with reducing mission operations costs through increased automation. This paper examines the operations procedures within NASA Mission Control Centers in order to uncover the level of automation that currently exists within them. Based on an assessment of mission operations procedures within three representative control centers, this paper recommends specific areas where there is potential for mission cost reduction through increased automation.
Topics: AERODYNAMIC FORCES, CIVIL AVIATION, GUSTS, NUMERICAL ANALYSIS, AVIONICS, COMFORT, FUSELAGES, ANGLE...
1,173
1.2K
Jul 11, 2010
07/10
by
NON
texts
eye 1,173
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Mechanisms developed for various aerospace applications are discussed. Specific topics covered include: boom release mechanisms, separation on space shuttle orbiter/Boeing 747 aircraft, payload handling, spaceborne platform support, and deployment of spaceborne antennas and telescopes.
Topics: AERODYNAMIC CHARACTERISTICS, NOSE FINS, AERODYNAMIC FORCES, LATERAL STABILITY, LONGITUDINAL...
256
256
Jul 6, 2010
07/10
by
DROEGE, K
texts
eye 256
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APPLICATIONS OF TELEOPERATOR MACHINES (REMOTE MANIPULATORS) AND ROBOTS IN VARIOUS AREAS OF TECHNOLOGY ARE DESCRIBED. THE SYNTELMANN TELEOPERATOR IS DISCUSSED IN DETAIL.
Topics: PRESSURE DISTRIBUTION, TRANSONIC WIND TUNNELS, TWO DIMENSIONAL FLOW, WIND TUNNEL WALLS, AERODYNAMIC...
218
218
Jul 6, 2010
07/10
by
ZWANZIG, M.; OELKERS, W
texts
eye 218
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THE PH-DEPENDENCE OF THE BIOLOGICAL INACTIVATION OF ALPHA-L-ASPARTYL-ANGIOTENSIN 2 (A) AND OF ALPHA-L-ASPARAGINYL-ANGIOTENSIN 2 (H) IN HUMAN PLASMA WAS COMPARED. IN ADDITION, THE PH-DEPENDENCE OF THE EDTA INHIBITION OF ANGIOTENSINASES AND ITS REACTIVATIONS BY DIVALENT METAL IONS WERE INVESTIGATED. BOTH SUBSTRATES ARE CLEAVED BY AT LEAST THREE ENZYMES WITH DIFFERENT PH OPTIMA. DISTINGUISHABLE CHARACTERISTICS OF THE A- AND H-INACTIVATING ENZYMES WERE FOUND IN ALL PH RANGES. ALSO COMPARED WAS THE...
Topics: AERODYNAMIC CHARACTERISTICS, PRESSURE DISTRIBUTION, ROTARY WINGS, TURBULENT FLOW, VORTICES,...
593
593
Jul 12, 2010
07/10
by
Colony, J. A
texts
eye 593
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Test sample acquisition and chemical analysis techniques for outgassing products from spacecraft, experiment modules, and support equipment is described. The reduction of test data to a computer compatible format to implement materials selection policies is described. A list of the most troublesome outgassing species is given and several materials correlations are discussed. Outgassing from solar panels, thermal blankets, and wire insulation are examined individually.
Topics: AERODYNAMIC FORCES, AIRCRAFT STRUCTURES, AIRSHIPS, BOUNDARY LAYER FLOW, PRESSURE DISTRIBUTION,...
1,072
1.1K
May 27, 2011
05/11
by
NON
texts
eye 1,072
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The Lewis Research Center of the National Aeronautics and Space Administration proposes to build a nuclear research reactor which will be located in the Plum Brook Ordnance Works near Sandusky, Ohio. The purpose of this report is to inform the Advisory Committee on Reactor Safeguards of the U. S. Atomic Energy Commission in regard to the design Lq of the reactor facility, the characteristics of the site, and the hazards of operation at this location. The purpose of this research reactor is to...
Topics: ANTIMISSILE MISSILES, INTERCONTINENTAL BALLISTIC MISSILES, FLIGHT PATHS, AERODYNAMIC FORCES,...
169
169
Jun 1, 2011
06/11
by
Pedersen, L.; Bualat, M.; Lees, D.; Smith, D. E.; Washington, R
texts
eye 169
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This paper describes an integrated demonstration of ground-based contingent planning, robust execution and autonomous instrument placement for the efficient exploration of a site by a prototype Mars rover.
Topics: AIRFOILS, FLOW MEASUREMENT, AIR FLOW, FLOW DIRECTION INDICATORS, PATENTS, LOW ASPECT RATIO, STRAIN...
238
238
Jul 5, 2010
07/10
by
Knuth, E. L.; Lefkowitz, B
texts
eye 238
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comment 0
No Abstract Available
Topics: COMPRESSIBILITY EFFECTS, CONTROL SURFACES, FLUTTER ANALYSIS, POTENTIAL FLOW, AERODYNAMIC FORCES,...
258
258
Jun 21, 2010
06/10
by
Pflueger, E
texts
eye 258
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comment 0
Fertilization of overmature frog eggs
Topics: FLIGHT PATHS, GLIDERS, TAKEOFF, WINCHES, AERODYNAMIC FORCES, CLIMBING FLIGHT, GROUND EFFECT...
434
434
Jul 23, 2010
07/10
by
Fusaro, Robert L.; Schrubens, Dale L
texts
eye 434
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A pin-on-disk tribometer was used to study the tribological properties of methyl alcohol-coal slurries. Friction coefficients, steel pin wear rates and wear surface morphological studies were conducted on AISI 440C HT and M-50 bearing steels which were slid dry and in solutions of methyl alcohol, methyl alcohol-fine coal particles, and methyl alcohol-fine coal particles-flocking additive. The latter was an oil derived from coal and originally intended to be added to the coal slurry to improve...
Topics: AERODYNAMIC FORCES, WINGS, LATERAL CONTROL, LIFT AUGMENTATION, ROLL, SPANWISE BLOWING, SCALING...
579
579
Jul 26, 2010
07/10
by
Bagwell, Ted G.; Lessard, Oscar J.; Rennie, John A.; Sloan, Sandra M.; Valentine, John D
texts
eye 579
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comment 0
No Abstract Available
Topics: AERODYNAMIC FORCES, CROSS SECTIONS, MOMENTS, SLENDER BODIES, STABILITY DERIVATIVES, COMPRESSIBLE...
331
331
Jul 11, 2010
07/10
by
HERRMANN, W. P
texts
eye 331
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METHODS IN CURRENT USE FOR DETERMINATION AND DIFFERENTIAL DIAGNOSIS OF SYSTEMIC LUPUS ERYTHEMATODES ARE SUMMARIZED AND DISCUSSED.
Topics: CONCORDE AIRCRAFT, FREE FLIGHT, GUST LOADS, SCALE MODELS, TRAJECTORY ANALYSIS, AERODYNAMIC...
279
279
Jun 2, 2011
06/11
by
Jones, Harr
texts
eye 279
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The ALS project plan goals are reducing cost, improving performance, and achieving flight readiness. ALS selects projects to advance the mission readiness of low cost, high performance technologies. The role of metrics is to help select good projects and report progress. The Equivalent Mass (EM) of a system is the sum of the estimated mass of the hardware, of its required materials and spares, and of the pressurized volume, power supply, and cooling system needed to support the hardware in...
Topics: AERODYNAMIC FORCES, CASCADE FLOW, UNSTEADY AERODYNAMICS, TURBOMACHINE BLADES, VIBRATION, LIFT,...
295
295
Jul 5, 2010
07/10
by
SCHNEIDER, E. J.; GRAFFI, A.; BIELKA, H.; VENKER, L
texts
eye 295
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THE RELATION BETWEEN MITOCHONDRIA AND GLYCOLYSIS IS STUDIED. IT IS FOUND THAT MITOCHONDRIA INFLUENCES GLYCOLYSIS EVEN WHEN GLUCOSE ALONE IS USED AS THE SUBSTRATE, AND NOT COMBINED WITH HDP.
Topics: AERODYNAMIC FORCES, AFTERBODIES, MISSILES, AERODYNAMIC CONFIGURATIONS, AEROTHERMODYNAMICS, MACH...
342
342
Jul 12, 2010
07/10
by
NON
texts
eye 342
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There are no author-identified significant results in this report.
Topics: AERODYNAMIC FORCES, AERODYNAMIC STABILITY, FLUTTER, WING PROFILES, AILERONS, BESSEL FUNCTIONS,...
239
239
Jul 9, 2010
07/10
by
LANDSTORFER, F.; HEINKE, H.; NIEDERMAIR, G
texts
eye 239
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THE ENERGY VORTEX OF A HEMISPHERICAL ANTENNA WAS MEASURED. THE ANTENNA CONSISTS OF A 27 CM DIAMETER DIELECTRIC HEMISPHERE WITH A RADIATOR ON THE SURFACE AND A CONDUCTING BASE PLANE. THIS RESULTS IN A MEASUREMENT RANGE IN THE RANGE 400-1250 MHZ. LINE OF CONSTANT PHASE, CONSTANT AMPLITUDE WERE MEASURED, AND ENERGY STREAMLINES WERE DETERMINED.
Topics: AIRFRAMES, COMPUTER PROGRAMS, STRUCTURAL ANALYSIS, STRUCTURAL STABILITY, UTILITY AIRCRAFT,...
198
198
Jul 5, 2010
07/10
by
PETYASHIN, I. B
texts
eye 198
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RESULTS FROM AN EXPERIMENTAL STUDY OF THE ACTIVITY OF A SOURCE OF ARTICULATION AND THE POSSIBILITY OF REDUCING IT ARE REPORTED. THE STATISTICAL FEATURES OF JUNCTURE IN THE RUSSIAN LANGUAGE ARE EXAMINED, ALONG WITH THE EFFECT OF PROLONGED, ARTIFICIAL JUNCTURE IN SPEECH ON ITS DISCRIMINATION.
Topics: ENGINE DESIGN, THRUST VECTOR CONTROL, TRANSITION FLOW, VERTICAL TAKEOFF AIRCRAFT, AERODYNAMIC...
496
496
texts
eye 496
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Tests conducted to evaluate the behavior of nonmetallic materials in hydrogen are described. The results of the flash and fire test are presented. The flash and fire test is used to evaluate the tendency of heated materials to ignite in a hydrogen atmosphere when subjected to an ignition source. The test represents a hydrogen parallel to a hazard condition known to exist in oxygen systems. Ten nonmetallic materials were evaluated to establish baseline data on the behavior of the materials and...
Topics: ATMOSPHERIC ENTRY, ATTITUDE CONTROL, OPTIMAL CONTROL, SPACECRAFT CONTROL, AERODYNAMIC FORCES, ANGLE...
236
236
Jul 11, 2010
07/10
by
Meecham, W. C.; Hurdle, P. M
texts
eye 236
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A 3.8 cm. model jet was operated in a wind tunnel with cross-flow in order to determine the effect on jet noise radiated characteristics. A method was developed for the determination of noise radiating characteristics of sources within reverberant wind tunnels; cross-correlation measurements were used. The averaging time in the cross-correlation is determined by the amount of background noise within the wind tunnel. It was found that cross-flow increases the radiated noise by 10 db. There was...
Topics: ELECTRIC GENERATORS, ENERGY CONVERSION, WINDPOWER UTILIZATION, AERODYNAMIC FORCES, ELECTRIC POWER...
A method for evaluating the Glauert coefficients from airfoil pressure distributions is investigated. The linear operating range of the airfoils in steady-state and periodic operating conditions are considered. A rational method for quantitatively characterizing airfoil pressure distributions relative to their geometry and aerodynamic operating environment is developed. The characteristics of the airfoil operating environment is determined from its measured pressure distribution.
Topics: NASA Technical Reports Server (NTRS), AIRFOILS, PRESSURE DISTRIBUTION, AERODYNAMIC FORCES, MACH...
1,370
1.4K
Jul 26, 2010
07/10
by
NON
texts
eye 1,370
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Control/Structures Integration program software needs, computer aided control engineering for flexible spacecraft, computer aided design, computational efficiency and capability, modeling and parameter estimation, and control synthesis and optimization software for flexible structures and robots are among the topics discussed.
Topics: CYLINDRICAL BODIES, HYPERSONIC FLOW, PRESSURE DISTRIBUTION, SCHLIEREN PHOTOGRAPHY, SHOCK WAVES,...
228
228
Jun 21, 2010
06/10
by
Hillard, M. E., Jr.; Ocheltree, S. L.; Storey, R. W
texts
eye 228
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Spectroscopic analysis of electron beam induced fluorescence in hypersonic helium flow
Topics: FLUTTER ANALYSIS, NACELLES, SCALE MODELS, TRANSPORT AIRCRAFT, AERODYNAMIC FORCES, JET AIRCRAFT,...
270
270
Jul 6, 2010
07/10
by
CRAMER, T
texts
eye 270
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EXPERIMENTS ON THE APPARENT INTERMEDIATE MEDIUM BETWEEN OBSERVER AND VISUAL OBJECTS ARE DESCRIBED. THESE EXPERIMENTS WERE CARRIED OUT IN ROOMS HAVING TWO CHAMBERS, SUBJECTED TO DIFFERENT LIGHTING CONDITIONS, AND IN OPEN FIELDS.
Topics: AERODYNAMIC CHARACTERISTICS, FORCE DISTRIBUTION, HELICOPTER PERFORMANCE, LIFT, ROTARY WINGS,...
204
204
Jul 11, 2010
07/10
by
KALININ, A. P.; LEONAS, V. B
texts
eye 204
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THE DIFFERENTIAL SCATTERING WAS STUDIED OF BEAMS OF HE/2 3S/ AND NE IN HE AND NE. THE EXPERIMENTAL FUNCTIONS FOR THE SYSTEMS HE-HE AND HE()-HE ARE COMPARED WITH FUNCTIONS CALCULATED FROM THE POTENTIALS. DEVIATIONS ARE FOUND BETWEEN THE CALCULATED AND THE MEASURED CURVES. THIS DEVIATION IS ELIMINATED FOR THE SYSTEM HE-HE BY MODIFYING THE TREND OF THE ADIABATIC TERM. FUNCTIONS OF THE POTENTIAL ENERGIES OF INTERACTION CORRESPONDING TO THE ADIABATIC TERM OF THE SYSTEM HE2 AND TO THAT OF THE SYSTEM...
Topics: COMPUTER PROGRAMS, TRAJECTORY OPTIMIZATION, AERODYNAMIC FORCES, DECISION MAKING, EQUATIONS OF...
The ability to perform an inclination change maximizes the maneuverability of an orbiting space vehicle. Most maneuvers utilize a combined plane change and orbital transfer to the new orbit. This costs more in terms of energy and fuel than an in-plane change of orbits. The amount of DV and fuel required for such an energyintensive inclination change exceeds the benefit of performing the maneuver. However, this paper demonstrates that a winged re-entry vehicle, based on the currently proposed...
Topics: Winged Re-entry Vehicle, Orbital Mechanics, Orbital Transfer, Perigee Collapse, Orbital Regulator,...
265
265
May 30, 2011
05/11
by
Dominguez, Jesus A.; Klinko, Steve; Ferrell, Bo
texts
eye 265
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The intelligent visual system detects anomalies or defects in real time under normal lighting operating conditions. The application is basically a learning machine that integrates fuzzy logic (FL), artificial neural network (ANN), and generic algorithm (GA) schemes to process the image, run the learning process, and finally detect the anomalies or defects. The system acquires the image, performs segmentation to separate the object being tested from the background, preprocesses the image using...
Topics: MULTIVARIATE STATISTICAL ANALYSIS, ORTHOGONAL FUNCTIONS, AERODYNAMIC FORCES, AERODYNAMIC...
The application is considered of vortex lattice techniques to the problem of describing the aerodynamics and performance of statically thrusting propellers. A numerical lifting surface theory to predict the aerodynamic forces and power is performed. The chordwise and spanwise loading is modelled by bound vortices fixed to a twisted flat plate surface. In order to eliminate any apriori assumptions regarding the wake shape, it is assumed the propeller starts from rest. The wake is generated in...
Topics: NASA Technical Reports Server (NTRS), AERODYNAMICS, HELICOPTER WAKES, VORTICES, AERODYNAMIC FORCES,...
597
597
Jul 12, 2010
07/10
by
NON
texts
eye 597
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The state of the art in nuclear pumped lasers is reviewed. Nuclear pumped laser modeling, nuclear volume and foil excitation of laser plasmas, proton beam simulations, nuclear flashlamp excitation, and reactor laser systems studies are covered.
Topics: COMPUTER SYSTEMS PROGRAMS, EQUATIONS OF MOTION, MATRICES (MATHEMATICS), AERODYNAMIC DRAG,...
The focus of this investigation was on the understanding and prediction of the nonlinear geometric (large displacements) dynamic response of functionally graded panels subjected to the severe acoustic, thermal, and mechanical/aerodynamic excitations expected for hypersonic vehicles. The phenomenological analysis centered more specifically on the differences observed in the response of metallic panels and those functionally graded while a pre-existing reduced order modeling strategy was...
Topics: DTIC Archive, ARIZONA STATE UNIV TEMPE, *AIRCRAFT PANELS, *DYNAMIC RESPONSE, AERODYNAMIC FORCES,...
391
391
Jul 5, 2010
07/10
by
Patterson, H. P.; Edmiston, R. P.; Connor, W. K
texts
eye 391
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A dynamic preferential runway system (DPRS) was developed for John F. Kennedy International Airport for the purpose of controlling short term noise exposure in the neighboring communities. The DPRS is a computer-aided procedure for optimum selection of runways from the standpoint of noise and is based upon a community disturbance model which takes into account flyover levels, size of exposed populations, time of day and week, and persistence of overflights. A preliminary evaluation of the DPRS...
Topics: DELTA WINGS, SPACE SHUTTLE BOOSTERS, SPACE SHUTTLE ORBITERS, WIND TUNNEL STABILITY TESTS,...
This work is an annotated bibliography of the scientific literature pertaining to methods of calculating the aerodynamic forces acting on an air vehicle in flight. The present segment of the work includes material reviewed by the author in the period July 1955 through September 1955. The more interesting papers and reports (from the viewpoint of the aerodynamicist) are discussed briefly; others are listed without comment.
Topics: DTIC Archive, Krzywoblocki, M Z, CHICAGO UNIV IL INST FOR SYSTEM RESEARCH, *AERODYNAMIC FORCES,...
This report summarizes results of stability analyses performed for a slender sharp cone with and without injection of air through a porous strip. The free-stream parameters are related to the experiments in the Caltech s T5 shock tunnel. The analysis is focused on pure aerodynamic effects in the framework of perfect gas model. It was shown that the injection leads to destabilization of acoustic modes in the near-field relaxation region. To reduce this detrimental effect it was suggested to...
Topics: DTIC Archive, MOSCOW INST OF PHYSICS AND TECHNOLOGY DOLGOPRUDNYI (RUSSIA), *BOUNDARY LAYER,...
Vortex dynamics of wakes generated by rectangular aspect-ratio 2 and 4 and two-dimensional pitching at plates in free stream are examined with direct numerical simulation and water tunnel experiments. Evolution of wake vortices comprised of tip, leading-edge and trailing-edge vortices is compared with force history for a range of pitch rates. The plate pivots about its leading edge with reduced frequency from pi/8 to pi/48, which corresponds to pitching over 1 to 6 chord lengths of travel....
Topics: DTIC Archive, FLORIDA STATE UNIV TALLAHASSEE DEPT OF MECHANICAL ENGINEERING, *WAKE, AERODYNAMIC...
The main trust of the Forum was: Aeroelasticity and Structural Dynamics. In particular, the Forum included the following topics: (1) unsteady aerodynamics and aeroelastic characteristics of aerospace structures, (2) structural modeling and optimization, (3) active control and smart structures, (4) certification and qualification, and (5) testing for validation.
Topics: DTIC Archive, ROME UNIV (ITALY), *SYMPOSIA, *AEROELASTICITY, *AIRCRAFT DESIGN, AERODYNAMIC...
200
200
May 27, 2011
05/11
by
Hanel, R. A
texts
eye 200
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The blackbody temperature and the albedo of a planet, and the variation of both parameters with latitude, longitude, and time, are of great value in understanding the climatic and meteorological conditions of the planet. An unchopped radiometer with a wide but restricted field of view is capable of such temperature and albedo measurements. Coated thermistors mounted in highly reflective cones serve as detectors. Their performance as sensor elements is analyzed in detail herein to prove the...
Topics: ATMOSPHERIC ENTRY, WEIGHT (MASS), AERODYNAMIC HEATING, DESCENT TRAJECTORIES, DECELERATION, DRAG,...
206
206
May 27, 2011
05/11
by
NON
texts
eye 206
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A heat shield for thermally insulating the leading edge of a wing of a spacecraft during ascent and reentry includes a plurality of rigid tiles. Each tile is formed with a pie-shaped element which interlocks with the complementarily-formed element of another tile. The combination of structure afforded by the pie-shaped elements substantially impedes hypersonic flow of any gases that might enter the gaps between tiles.
Topics: UPPER ATMOSPHERE, ANGULAR VELOCITY, MARS (PLANET), MARS ATMOSPHERE, VERTICAL DISTRIBUTION,...
Turbomachinery blades are subject to aerodynamic forces that can lead to high-cycle-fatigue (HCF) failures. These failures will only increase as engineers begin to design blades without shrouds or as integrally bladed disks (blisks). These new designs will decrease blade damping significantly because the mechanical damping from shroud and blade joints will be eliminated. Also, it is difficult to design dampers for the engine environment with its extremely high centrifugal loads and high...
Topics: NASA Technical Reports Server (NTRS), TURBOMACHINERY, BLADES, AERODYNAMIC FORCES, FAILURE,...
226
226
May 31, 2011
05/11
by
Smith, Phillip J.; Billings, Charles; McCoy, C. Elaine; Orasanu, Judit
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The air traffic management system in the United States is an example of a distributed problem solving system. It has elements of both cooperative and competitive problem-solving. This system includes complex organizations such as Airline Operations Centers (AOCs), the FAA Air Traffic Control Systems Command Center (ATCSCC), and traffic management units (TMUs) at enroute centers and TRACONs, all of which have a major focus on strategic decision-making. It also includes individuals concerned more...
Topics: ANGLE OF ATTACK, TRANSONIC WIND TUNNELS, WIND TUNNEL MODELS, WIND TUNNEL TESTS, ERROR ANALYSIS,...
This AFOSR YIP project provides a comprehensive understanding of the unique dynamics and control characteristics of tailless micro aerial vehicle equipped with flexible, articulated wings. This project has successfully demonstrated the ability to stabilize and control the robotic flapping testbed by using the phase synchronized nonlinear oscillators inspired by the central pattern generators in spinal cord. Furthermore, it is shown that the dihedral angle of the wing can be varied symmetrically...
Topics: DTIC Archive, ILLINOIS UNIV AT URBANA-CHAMPAIGN, *DRONES, *FLAPS(CONTROL SURFACES), AERODYNAMIC...
346
346
Jul 5, 2010
07/10
by
Foster, J. D.; Kirk, R. F
texts
eye 346
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Results of a design study and preliminary design of a space qualified Nd:YAG laser are presented. A theoretical model of the laser was developed to allow the evaluation of the effects of various parameters on its performance. Various pump lamps were evaluated and sum pumping was considered. Cooling requirements were examined and cooling methods such as radiation, cryogenic and conductive were analysed. Power outputs and efficiences of various configurations and the pump and laser lifetime are...
Topics: AERODYNAMIC FORCES, TRANSONIC WIND TUNNELS, LAUNCH VEHICLES, MOMENTS, NUCLEAR PROPULSION, REUSABLE...
A computer program for calculating the elastic element forces and strain energy distribution for normal mode shapes is presented. The subjects discussed are: (1) revised aerodynamic force representation, (2) flap aerodynamics, (3) chordwise motions and aerodynamic forces, (4) wing-tail interaction, and (5) gust analysis. An aircraft configuration used in sample gust analysis is included.
Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC FORCES, AEROELASTICITY, COMPUTER PROGRAMS, GUST...
