437
437

Jul 6, 2010
07/10

by
BOR-RAMENSKIY, A. Y.; KULESHOV, V. S.; LAKOTA, N. A.; LOBACHEV, V. I

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SOME BASIC MECHANICAL REQUIREMENTS FOR THE CONSTRUCTION OF MANIPULATORS DESIGNED TO PERFORM A WIDE RANGE OF COMPLEX TASKS AT A DISTANCE FROM THE OPERATOR ARE REVIEWED. THE KINEMATICS AND DYNAMICS OF THE HUMAN ARM AND HAND ARE OUTLINED, AND RELEVANT CONSTRUCTION PRINCIPLES ARE ABSTRACTED. THESE PRINCIPLES ARE THEN, RATHER EFFECTIVELY, APPLIED TO IMITATIVE REMOTE CONTROL MANIPULATORS WITH BOTH ACTION AND PASSIVE FEEDBACK.

Topics: CURVATURE, DIFFUSERS, SLOTS, AXISYMMETRIC FLOW, SUBSONIC FLOW, SUCTION

2,021
2.0K

Jun 18, 2010
06/10

by
Babenko, K. I.; Lyubimov, A. N.; Rusanov, V. V.; Voskresenskiy, G. P

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Nonaxisymmetric three-dimensional flow field of ideal gas about smooth body of revolution

Topics: AXISYMMETRIC FLOW, BODY OF REVOLUTION, FLOW FIELD, IDEAL GAS, THREE-DIMENSIONAL FLOW, BODIES OF...

219
219

May 6, 2010
05/10

by
Lifshits, Yu. B.; Ryzhov, O. S

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Axisymmetric transonic flow in Laval nozzles with circular cross section

Topics: ACOUSTIC VELOCITY, AXISYMMETRIC FLOW, LAVAL NUMBER, NOZZLE FLOW, SYMMETRY, TRANSONIC FLOW, NOZZLE...

633
633

Jul 12, 2010
07/10

by
Jaffe, L. D

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Methods for optimizing parabolic dish solar collectors and the consequent effects of various optical, thermal, mechanical, and cost variables are examined. The most important performance optimization is adjusting the receiver aperture to maximize collector efficiency. Other parameters that can be adjusted to optimize efficiency include focal length, and, if a heat engine is used, the receiver temperature. The efficiency maxima associated with focal length and receiver temperature are relatively...

Topics: AXISYMMETRIC FLOW, MEASURING INSTRUMENTS, TURBULENCE, DATA RECORDING, DIGITAL DATA, GRAPHS...

292
292

Jul 23, 2010
07/10

by
Pelin, Alex; Morrow, Pau

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An automatic program generator which creates PROLOG programs from input/output specifications is described. The generator takes as input descriptions of the input and output data types, a set of transformations and the input/output relation. Abstract data types are used as models for data. They are defined as sets of terms satisfying a system of equations. The tests, the transformations and the input/output relation are also specified by equations.

Topics: AUGMENTATION, AXISYMMETRIC FLOW, EXCITATION, JET MIXING FLOW, PLANE WAVES, SATURATION, BOUNDARY...

388
388

Jul 11, 2010
07/10

by
NON

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In October 1958, the National Aeronautics and Space Agency (NASA) was asked to absorb the Army Ballistic Missile Agency (ABMA) space group, but an agreement was reached two months later for the group to remain with the Army while being responsive to NASA. This decision was to be reconsidered and reversed within a year. The competition in large launch vehicles between NASA, ARPA (Advanced Research Projects Agency), Air Force, and Army begun in 1958, continued into 1959. The government settled...

Topics: AERODYNAMICS, BOUNDARY LAYERS, SEPARATED FLOW, AXISYMMETRIC FLOW, BOUNDARY CONDITIONS, COMPUTATION,...

355
355

Jul 5, 2010
07/10

by
WALTER, B

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DISADVANTAGES OF THE PRESENT TYPE OF LIGHTNING PROTECTION ARE DISCUSSED. IT IS CONCLUDED FROM TESTS AND LIGHTNING STATISTICS THAT LIGHTNING RODS WHICH ARE SEPARATE FROM THE BUILDING TO BE PROTECTED OFFER THE BEST PROTECTION.

Topics: EQUATIONS OF MOTION, FLOW EQUATIONS, NOZZLE FLOW, TWO DIMENSIONAL FLOW, AXISYMMETRIC FLOW, FLOW...

233
233

Jul 23, 2010
07/10

by
Sarthou, CH

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No Abstract Available

Topics: AXISYMMETRIC FLOW, GAS DYNAMICS, STEADY STATE, TWO DIMENSIONAL FLOW, REPORTS, THREE DIMENSIONAL...

666
666

Jul 12, 2010
07/10

by
Perkins, P. J

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No Abstract Available

Topics: AXISYMMETRIC FLOW, DROPS (LIQUIDS), ELLIPSOIDS, FINENESS RATIO, IMPINGEMENT, BODIES OF REVOLUTION,...

1,041
1.0K

Jun 21, 2010
06/10

by
Kuznetsova, T. D., et al

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Tables of characteristic exponents of Mathieu equations

Topics: APPROXIMATION, AXISYMMETRIC FLOW, HYDRODYNAMICS, INCOMPRESSIBLE FLUIDS, DIFFERENTIAL EQUATIONS,...

167
167

Jul 23, 2010
07/10

by
Zheng, Chingf

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This paper discusses the reliability of the flow pattern obtained with the surface oil flow technique in detail. It successfully introduces a mathematical method to determine the 3-D coordinates of a surface point based on a single photograph. The flow separation positions of the classical plate and blunt cone model were calculated. The results indicate that in most cases the surface oil flow technique can be applied not only as a qualitative but also a quantitative experimental technique.

Topics: COMPUTATION, HYPERSONIC SPEED, JET FLOW, NUMERICAL ANALYSIS, PLUMES, AXISYMMETRIC FLOW, SHEAR...

Topics: DTIC Archive, BOEING SCIENTIFIC RESEARCH LABS SEATTLE WA, *DRAG, *CONICAL BODIES, *HYPERSONIC FLOW,...

295
295

Jul 23, 2010
07/10

by
Carson, George T., Jr.; Lamb, Milto

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An investigation was conducted in the Langley 16-Foot Transonic Tunnel to determine the aeropropulsive performance characteristics (the aerodynamic quantities affected by propulsion) of 13 isolated combined turbojet/ramjet nozzle configurations. These configurations simulated the variable-geometry features of two nozzle designs designated as the multiple-expansion ramp nozzle (MERN) and the composite contour nozzle (CCN). Test data were obtained at static conditions and at Mach numbers of 0.60,...

Topics: BEARING (DIRECTION), POTENTIAL FLOW, PRANDTL NUMBER, DEFLECTION, FLAT PLATES, FLUID FLOW, HYDRAULIC...

200
200

Jul 9, 2010
07/10

by
LUKASHEVICH, H. L.; MAROV, M. Y.; FEYGELSON, Y. M

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ILLUMINATION IN THE VENUSIAN ATMOSPHERE WAS FIRST MEASURED ON THE VENERA 8 AUTOMATIC STATION. THE PRINCIPAL FINDING WAS THAT THE DENSE VENUSIAN MOLECULAR ATMOSPHERE ENCLOSED FROM ABOVE BY THE CLOUD LAYER TRANSMITS SOLAR LIGHT TO THE PLANETARY SURFACE, THOUGH VERY GREATLY ATTENUATED. TWO ATMOSPHERIC LAYERS WITH DIFFERING OPTICAL DENSITY WERE ALSO FOUND: FROM 50 TO 35 KM, AND FROM 35 KM TO THE SURFACE. TWO MODELS OF THE VENUSIAN ATMOSPHERE WERE EXAMINED TO FIND THE ONE PROVIDING CLOSER AGREEMENT...

Topics: AXISYMMETRIC FLOW, BODIES OF REVOLUTION, POTENTIAL FLOW, ANNULAR NOZZLES, COWLINGS, ENGINE INLETS,...

150
150

May 28, 2011
05/11

by
Goodman, Jindr

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Minor constituents play an important role in atmospheric chemistry and serve as tracers in transport and mixing studies in tropospheric-stratospheric exchange processes. Measurements of trace gases are essential to an understanding of the mechanisms by which minor constituents originating in the troposphere, both naturally occurring and anthropogenic, reach the stratosphere. Many of these gases are sources of species directly involved in the chemistry of ozone depletion in the stratosphere and...

Topics: SOUND PROPAGATION, LININGS, DUCTS, AXISYMMETRIC FLOW, EMISSION, COMPUTATION, TURBULENT FLOW,...

This article reviews the computational work on steady axisymmetric gas flow carried out at the Computational Center of Moscow State University between 1957 and 1962, The work was undertaken by scientific workers of the Institute of Mechanics of Moscow State University, undergraduate and graduate students of the University, members of other organizations, and the regular staff of the Computational Center. The project was headed by Academician G. I. Petrov. This article is of an informative...

Topics: DTIC Archive, Roslyakov, G S, MOSCOW STATE UNIV (USSR), *GAS DYNAMICS, RUSSIAN LANGUAGE, RUSSIA,...

507
507

May 6, 2010
05/10

by
Chow, W. L

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Axisymmetric and annular supersonic nozzle profiles

Topics: ANNULAR NOZZLES, SUPERSONIC NOZZLE, ANNULI, AXISYMMETRIC BODIES, AXISYMMETRIC FLOW, SUPERSONIC...

Topics: DTIC Archive, Dorsch, Robert G, NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON DC,...

235
235

Jun 27, 2010
06/10

by
Gade, D. W.; Wiley, F. L

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Device for rapid adjustment and maintenance of temperature in electronic components

Topics: AIR INTAKES, GAS JETS, NOISE REDUCTION, SUPERSONIC AIRCRAFT, TRANSPORT AIRCRAFT, TURBULENT JETS,...

The effect of wing span loading on the development of fully rolled up wing trailing vortices is discussed. It is shown that parabolic wing loadings produce potential flow maximum core rotary speeds which are finite and less than fifty percent of the downwash speeds at the plane of symmetry. The development of turbulent cores is analyzed and core growth is predicted to occur as the two thirds power of time whereas the peak velocities fall off as the inverse one third power. Axial flow effects of...

Topics: DTIC Archive, Brown, Clinton E, HYDRONAUTICS INC LAUREL MD, *VORTICES, *AVIATION SAFETY,...

217
217

Jun 2, 2011
06/11

by
Lary, D. J.; Mueller, M. D.; Mussa, H. Y

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Neural networks are ideally suited to describe the spatial and temporal dependence of tracer-tracer correlations. The neural network performs well even in regions where the correlations are less compact and normally a family of correlation curves would be required. For example, the CH4-N2O correlation can be well described using a neural network trained with the latitude, pressure, time of year, and CH4 volume mixing ratio (v.m.r.). In this study a neural network using Quickprop learning and...

Topics: AXISYMMETRIC FLOW, MATHEMATICAL MODELS, COMPUTATIONAL FLUID DYNAMICS, STRESS ANALYSIS, NOZZLE FLOW,...

An engineering prediction method and associated computer code VTXCLD are presented which predict nose vortex shedding from circular and noncircular bodies in subsonic flow at angles of attack and roll. The axisymmetric body is represented by point sources and doublets, and noncircular cross sections are transformed to a circle by either analytical or numerical conformal transformations. The leeward vortices are modeled by discrete vortices in cross-flow planes along the body; thus, the...

Topics: DTIC Archive, Mendenhall, Michael R, NIELSEN ENGINEERING AND RESEARCH INC MOUNTAIN VIEW CA, *VORTEX...

279
279

Jun 21, 2010
06/10

by
Dubinskaya, N. V.; Gzhelyak, R. A

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Application of method of characteristics to calculations of nonequilibrium supersonic air flow past blunted cones

Topics: AXISYMMETRIC FLOW, CONICAL FLOW, GAS STREAMS, INVISCID FLOW, SLENDER CONES, SUPERSONIC FLOW,...

246
246

Jun 18, 2010
06/10

by
Pogorelov, A. V

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Stability of axially symmetric deformation of axially symmetric shells for concentrated force and uniform outer pressure loading systems

Topics: AXIAL STRAIN, SYMMETRY, AXISYMMETRIC DEFORMATION, LOADING, SHELL STABILITY, AXISYMMETRIC FLOW,...

Rayleigh-Taylor fluid instabilities are studied in the ideal magnetohydrodynamic (MHD) limit by applying boundary integral mathematical formulations to solve Laplace's equation with Dirichlet conditions on complicated boundaries. Instabilities in both the flute and sausage modes are studied for an accelerating thin cylindrical plasma, and calculations demonstrate the basic nonlinear dynamics of the z-pinch geometry. The dynamics and mathematics of plane thin shells and thin shells in...

Topics: DTIC Archive, Baker,Gregory R, CAMBRIDGE HYDRODYNAMICS INC MA, *MAGNETOHYDRODYNAMICS, SURFACES,...

5,525
5.5K

Jul 11, 2010
07/10

by
Bornemann, W. E.; Surber, T. E

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An overview of the wind tunnel program is given and aerodynamic characteristics of the final configuration are described. Aerodynamic parameters critical to definition of Orbiter entry control and performance are identified. Trim capability and stability and control characteristics are discussed at critical regions in the entry trajectory. Methods are described to define reaction control rocket effectiveness and aerodynamic interactions during the initial portion of entry. At hypersonic speeds,...

Topics: ANGLES (GEOMETRY), AXISYMMETRIC FLOW, EXTERNALLY BLOWN FLAPS, JET IMPINGEMENT, OBLIQUE WINGS,...

173
173

May 23, 2011
05/11

by
Pinelli,Thomas E.; Golich, Vicki L

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Economists, management theorists, business strategists, and governments alike recognize knowledge as the single most important resource in today's global economy. Because of its relationship to technological progress and economic growth, many governments have taken a keen interest in knowledge; specifically its production, transfer, and use. This paper focuses on the technical report as a product for disseminating the results of aerospace research and development (R&D) and its use and...

Topics: AXISYMMETRIC FLOW, IMPELLERS, DISTORTION, SURGES, CENTRIFUGAL COMPRESSORS, UNSTEADY FLOW, ROTATING...

590
590

Jun 21, 2010
06/10

by
NON

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Describing systems and facilities for the Deep Space Network.

Topics: AIR BREATHING ENGINES, INTAKE SYSTEMS, MACH NUMBER, WIND TUNNEL MODELS, AERODYNAMIC...

574
574

Jul 12, 2010
07/10

by
Jones, J. S.; Graves, S. R

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The large stiffness-to-weight and strength-to-weight ratios of graphite composite in combination with the 600 F structural capability of the polyimide matrix can reduce the total structure/TPS weight of reusable space vehicles by 20-30 percent. It is inevitable that with planned usage of GR/PI structural components, damage will occur either in the form of intrinsic flaw growth or mechanical damage. Research and development programs were initiated to develop repair processes and techniques...

Topics: AXISYMMETRIC FLOW, TURBULENCE, CIRCULAR CYLINDERS, CRITICAL FLOW, FLOW VISUALIZATION, WATER TUNNEL...

A method of obtaining the probability density function (PDF) of local properties from path integrated measurements is described. The approach uses a discrete probability function (DPF) method to infer the PDF of the local extinction coefficient from measurements of the PDFs of the path integrated transmittance. The local PDFs obtained using the method are compared with those obtained from direct intrusive measurements in propylene/air and ethylene/air diffusion flames. The results of this...

Topics: NASA Technical Reports Server (NTRS), DIFFUSION FLAMES, EXTINCTION, PROBABILITY DENSITY FUNCTIONS,...

The equation for axi-symmetric magnetohydrostatic equilibria in stationary conductive fluid is re-examined. Spheroidal magnetic conducting vortices are shown as examples of equilibrium configurations. Then a circulating sphere of viscous conducting fluid moving slowly along an aligned spatially uniform magnetic field, varying linearly with time, is shown to be a megneto hydrodynamic vortex which satisfies all reason able boundary conditions for real fluids. The possibility of experimental...

Topics: DTIC Archive, O'Brien, Vivian, JOHNS HOPKINS UNIV LAUREL MD APPLIED PHYSICS LAB, *VORTICES,...

The time-dependent, turbulent mean-flow, Reynolds stress, and heat flux equations in mass-averaged dependent variables are presented. These equations are given in conservative form for both generalized orthogonal and axisymmetric coordinates. For the case of small viscosity and thermal conductivity fluctuations, these equations are considerably simpler than the general Reynolds system of dependent variables for a compressible fluid and permit a more direct extension of low speed turbulence...

Topics: NASA Technical Reports Server (NTRS), FLOW CHARACTERISTICS, FLOW DISTRIBUTION, FLOW EQUATIONS,...

This report consists of two abstracts submitted for possible presentation at the AIAA Aerospace Science Meeting to be held in January 2005. Since the submittal of these abstracts we are continuing refinement of the model coefficients derived for the case of a variable Turbulent Prandtl number. The test cases being investigated are a Mach 9.2 flow over a degree ramp and a Mach 8.2 3-D calculation of crossing shocks. We have developed an axisymmetric code for treating axisymmetric flows. In...

Topics: NASA Technical Reports Server (NTRS), PRANDTL NUMBER, SCHMIDT NUMBER, TURBULENT COMBUSTION,...

Underexpanded axisymmetric jets are studied numerically using a full Navier-Stokes solver. Emphasis has been given to supersonic and hypersonic jets in supersonic and hypersonic ambient flows, a phenomenon previously overlooked. It is demonstrated that the shear layers and shock patterns in a jet plume can be captured without complicated viscous/inviscid and subsonic/supersonic coupling schemes. In addition, a supersonic pressure relief effect has been identified for underexpanded jets in...

Topics: NASA Technical Reports Server (NTRS), COMPUTATION, HYPERSONIC SPEED, JET FLOW, NUMERICAL ANALYSIS,...

Topics: DTIC Archive, HILLER AIRCRAFT CORP PALO ALTO CA, *AERIAL PROPELLERS, *SHROUDED PROPELLERS,...

An important feature of many flows encountered in practice (such as inturbomachinery) is the fact that the streamlines may be curved, thereby introducing a pressure gradient in the direction perpendicular to the main flow direction. The purpose of the present research is to isolate the effects of curvature (swirl) on the turbulence and hence the transport properties. The experimental effort is concerned with mapping out the details of the developing axial and decaying tangential velocity fields...

Topics: DTIC Archive, Scott, Charles J, MINNESOTA UNIV MINNEAPOLIS HEAT TRANSFER LAB, *AXISYMMETRIC FLOW,...

An approximate method for calculating the noise generated by a turbulent flow within a semi-infinite duct of arbitrary cross section is developed. It is based on a previously derived high-frequency solution to Lilley's equation, which describes the sound propagation in transversely-sheared mean flow. The source term is simplified by assuming the turbulence to be axisymmetric about the mean flow direction. Numerical results are presented for the special case of a ring source in a circular duct...

Topics: NASA Technical Reports Server (NTRS), SOUND PROPAGATION, EMISSION, COMPUTATION, TURBULENT FLOW,...

The cell-vertex schemes due to Ni and Jameson, et al. have been subjected to a theoretical analysis of their truncation error. The analysis confirms the authors' claims for second-order accuracy on smooth grids, but shows that the same accuracy cannot be obtained on arbitrary grids. It is shown that the schemes have a unique generalization to axisymmetric flow that preserves the second-order accuracy.

Topics: NASA Technical Reports Server (NTRS), COMPRESSIBLE FLOW, ERROR ANALYSIS, EULER EQUATIONS OF MOTION,...

The blast wave solutions for the axisymmetric flow fields associated with a family of power law shocks, y sub s equals approximately x to the n power, were modified to properly account for the entropy layer near the surface of the body. The method of inner and outer expansions was used. It was shown that this method is of limited usefulness for n only slightly greater than 1/2 due to the slow convergence of the inner expansions, but for (gamma 2)/(3 gamma 2) less than or equal to n 1 the...

Topics: DTIC Archive, Lee, Jr, James T, TRW SPACE TECHNOLOGY LABS REDONDO BEACH CA, *SHOCK WAVES, *INVISCID...

An attempted asymptotic series solution in terms of inverse powers of the axial distance for the incompressible laminar wake far behind a very slender cylinder breaks down at an early stage. The PLK method is applied to the problem and yields a uniformly valid asymptotic solution. The method of approach used should be of interest to researchers in fluid mechanics concerned with the solution of singular perturbation problems, while the results should be of interest to those involved in wake...

Topics: DTIC Archive, RAND CORP SANTA MONICA CA, *CYLINDRICAL BODIES, *WAKE, APPROXIMATION(MATHEMATICS),...

Topics: DTIC Archive, Gertsenshteyn,S Ya, FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO, *AERODYNAMIC...

In a previous paper, the weakly nonlinear interaction of a pair of axisymmetric lower branch Tollmien-Schlichting instabilities in cylindrical supersonic flows was considered. Here the possibility that nonaxisymmetric modes might also exist is investigated. In fact, it is found that such modes do exist and, on the basis of linear theory, it appears that these modes are the most important. The nonaxisymmetric modes are found to exist for flows around cylinders with nondimensional radius alpha...

Topics: NASA Technical Reports Server (NTRS), AXISYMMETRIC FLOW, SUPERSONIC FLOW, VISCOUS FLOW, CYLINDRICAL...

The physics of accretion flow very close to a black hole is dominated by several general relativistic effects. It cannot be described by the standard Shakura Sunyaev model or by its relativistic version developed by Novikov and Thome. The most important of these effects is a dynamical mass loss from the inner edge of the disk (Roche lobe overflow). The relativistic Roche lobe overflow induces a strong advective cooling, which is sufficient to stabilize local, axially symmetric thermal and...

Topics: NASA Technical Reports Server (NTRS), ACCRETION DISKS, ANGULAR MOMENTUM, AXISYMMETRIC FLOW, BLACK...

An experimental investigation made to determine the flow parameter profiles across the boundary layer on contoured, axisymmetric hypersonic nozzles is described. The pitot pressure and total temperature profiles measured across the boundary layers on nozzles of Mach number seven and twelve are shown in graphical form. The static temperature and velocity profiles, calculated with the assumption of constant static pressure across the boundary layer, are given. A correlation is shown to exist...

Topics: DTIC Archive, Scaggs, Norman E, AEROSPACE RESEARCH LABS WRIGHT-PATTERSON AFB OH, *BOUNDARY LAYER,...

The Eady model of baroclinic instability applied to a rotating channel with Ekman layers at the top and bottom is extended to a beta-plane channel. Changes in the shape and position of the boundary separating the regions of axially symmetric and wavelike motion are predicted.

Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC MODELS, BAROCLINIC WAVES, FLOW STABILITY,...

115
115

Jul 26, 2010
07/10

by
Bezdek, James C

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Kohonen's feature maps approach to clustering is often likened to the k or c-means clustering algorithms. Here, the author identifies some similarities and differences between the hard and fuzzy c-Means (HCM/FCM) or ISODATA algorithms and Kohonen's self-organizing approach. The author concludes that some differences are significant, but at the same time there may be some important unknown relationships between the two methodologies. Several avenues of research are proposed.

Topics: AXISYMMETRIC FLOW, MODULATION, REYNOLDS STRESS, SUPERSONIC SPEED, BOUNDARY LAYER FLOW, BOUNDARY...

A new method is presented for calculating the hydrodynamic coefficients of axisymmetric bodies. The method utilizes an extended version of the Douglas potential flow computer program for axisymmetric bodies to calculate the potential and velocity distribution along the body required for the determination of the forces and moment acting on the body. Based on a comparison with experiment limited to one body shape, the method yields values of the hydrodynamic coefficients for blunt- or flat-based...

Topics: DTIC Archive, NAVAL ORDNANCE TEST STATION CHINA LAKE CA, *BLUNT BODIES, *COMPUTER PROGRAMMING,...

An experimental study of the turbelent mixing of subsonic axisymmetric gas streams was conducted. Hydrogen-air and air-air mixing systems were studied, and the velocity ratio (jet velocity/outer stream velocity) was varied from 2.4 to 6.3. Special emphasis is placed on (1) the centerline decay and radial profile shapes of composition, velocity, and total enthalpy and (2) the relationships between the turbulent transport of mass, momentum, and energy. The major conclusions drawn for this...

Topics: DTIC Archive, Chriss, D E, ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN, *JET MIXING FLOW,...

A model for the small-scale structure of turbulence is reformulated in such a way that it may be conveniently computed. The model is an ensemble of randomly oriented structured two dimensional vortices stretched by an axially symmetric strain flow. The energy spectrum of the resulting flow may be expressed as a time integral involving only the enstrophy spectrum of the time evolving two-dimensional cross section flow, which may be obtained numerically. Examples are given in which a k(exp -5/3)...

Topics: NASA Technical Reports Server (NTRS), ASYMPTOTIC SERIES, AXISYMMETRIC FLOW, TURBULENCE, TURBULENCE...

A circular jet was excited simultaneously by two different harmonically related tones. Data for three pairs of Strouhal numbers (St(D) = f*D/U (sub j) = 0.2 and 0.4, 0.3 and 0.6, 0.4 and 0.8). For each case the initial phase difference between the two waves was varied in steps of 45 deg, for one full cycle and the level of the fundamental and subharmonic forcing were varied independently over the range of 0.1 to 7 percent of the jet exit velocity. Our initial findings concurred with published...

Topics: NASA Technical Reports Server (NTRS), AMPLITUDES, AXISYMMETRIC FLOW, EXCITATION, HARMONICS, JET...