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Shock-turbulence interaction and the generation of noise

Description: Report presenting the interaction of a convected field of turbulence with a shock wave, which has been analyzed to yield the modified turbulence, entropy spottiness, and noise generated downstream of the shock. The results in this report are applicable quantitatively to flow in ducts or channels containing normal shocks.
Date: July 1954
Creator: Ribner, H. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Turbulent shear spectra and local isotropy in the low-speed boundary layer

Description: "From measurements of turbulent shear spectra together with previously reported longitudinal turbulent energy spectra, the concept of local isotropy in a low-speed boundary layer was examined. Results of these measurements and measurements of the time derivatives of turbulent velocities in the x- and y- directions for various frequency bands showed no evidence of local isotropy in the boundary layer. Several methods (based on isotropy) of evaluating the turbulent dissipation term failed to give… more
Date: September 1956
Creator: Sandborn, Virgil A. & Braun, Willis H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preliminary study of applied load factors in bumpy air

Description: Theoretical relations involved in the study are reviewed to furnish a basis upon which experimental data can be properly analyzed. The structure of the atmosphere in relation to the load-factor problem is briefly discussed, and the acceleration data obtained on a number of flights with various airplanes are presented and analyzed to the extent that the results are applicable to n=any airplane.
Date: April 1931
Creator: Rhode, Richard V. & Lundquist, Eugene E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical calculation of the power spectra of the rolling and yawing moments on a wing in random turbulence

Description: The correlation functions and power spectra of the rolling and yawing moments on an airplane wing due to the three components of continuous random turbulence are calculated. The rolling moments to the longitudinal (horizontal) and normal (vertical) components depend on the spanwise distributions of instantaneous gust intensity, which are taken into account by using the inherent properties of symmetry of isotropic turbulence. The results consist of expressions for correlation functions or spectr… more
Date: September 6, 1956
Creator: Eggleston, John M. & Diederich, Franklin W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preliminary Investigation in the NACA Low-Turbulence Tunnel of Low-Drag Airfoil Sections Suitable for Admitting Air at the Leading Edge

Description: From Summary: "An investigation was carried out in the NACA low-turbulence tunnel to develop low-drag airfoil sections suitable for admitting air at the leading edge. A thickness distribution having the desired type of pressure distribution was found from tests of a flexible model. Other airfoil shapes were derived from this original shape by varying the thickness, the camper, the leading-edge radius, and the size of the leading-edge opening. Data are presented giving the characteristics of the… more
Date: July 1942
Creator: von Doenhoff, Albert E. & Horton, Elmer A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An analysis of the indications of the University of Chicago airborne turbulence indicator in gusty air

Description: From Introduction: "The present report has been prepared to discuss the indications obtained from the University of Chicago turbulence indicator in relation to simultaneous measurement of atmospheric gustiness made by the NACA, which are summarized herein."
Date: August 1946
Creator: Tolefson, H. B. & Pratt, K. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent Results of Turbulence Research

Description: The first sections of this report deal with two prominent questions, namely the origin of turbulence and the characteristics of turbulent currents. In the third section conclusions are drawn for the flow along a rough wall, whereby an important relation for the velocity distribution is revealed. The principles are also applied to straight rough and smooth tubes.
Date: August 1933
Creator: Prandtl, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Summary of Turbulence Data Obtained During United Air Lines Flight Evaluation of an Experimental C Band (5.5 cm) Airborne Weather Radar

Description: "Data on atmospheric turbulence in the vicinity of thunderstorms obtained during a flight evaluation of an experimental C band (5.5 cm) airborne radar are summarized. The turbulence data were obtained with an NACA VGH recorder installed in a United Air Lines DC-3 airplane" (p. 1).
Date: June 17, 1954
Creator: Coe, E. C. & Fetner, M. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some Basic Laws of Isotropic Turbulent Flow

Description: An Investigation is made of the diffusion of artificially produced turbulence behind screens or other turbulence producers. The method is based on the author's concept of disturbance moment as a certain theoretically well-founded measure of turbulent disturbances.
Date: September 1945
Creator: Loitsianskii, L. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Theories of Turbulence

Description: "The theory of turbulence reached its full growth at the end of the 19th century as a result of the work by Boussinesq and Reynolds. It then underwent a long period of stagnation which ended under the impulse given to it by the development of wind tunnels caused by the needs of aviation. Numerous researchers, attempted to put Reynolds' elementary statistical theory into a more precise form. During the war, some isolated scientists - von Weizsacker and Heisenberg in Germany, Kolmogoroff in Russi… more
Date: October 1955
Creator: Agostini, L. & Bass, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Shock-turbulence interaction and the generation of noise

Description: Interaction of convected field of turbulence with shock wave is analyzed to yield modified turbulence, entropy spottiness, and noise generated downstream of the shock. Analysis is generalization of single-spectrum-wave treatment of NACA-TN-2864. Formulas for spectra and correlations are obtained. Numerical calculations yield curves of rms velocity components, temperature, pressure, and noise in db against Mach number for m = 1 to infinity; both isotropic and strongly axisymmetric (lateral/longi… more
Date: June 3, 1954
Creator: Ribner, H. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The effect of turbulence on the drag of flat plates

Description: "In determining the effect of turbulence on the forces exerted on bodies in the air stream of a wind tunnel, it is commonly assumed that the indications of the standard Pitot-static tube used to determine the air speed are not dependent on the turbulence. To investigate the truth of this assumption, the drag of a normally exposed flat plate, the difference in pressure between the front and rear of a thin circular disk, the rate of rotation of a vane anemometer, and the pressure developed by a s… more
Date: June 22, 1935
Creator: Schubauer, G. B. & Dryden, H. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of turbulence in wind-tunnel measurements

Description: This paper gives some quantitative measurements of wind tunnel turbulence and its effect on the air resistance of spheres and airship models, measurements made possible by the hot wire anemometer and associated apparatus in its original form was described in Technical Report no. 320 and some modifications are presented in an appendix to the present paper. One important result of the investigation is a curve by means of which measurements of the air resistance of spheres can be interpreted to gi… more
Date: August 20, 1929
Creator: Dryden, H. L. & Kuethe, A. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Turbulence-Flame Interactions in Type Ia Supernovae

Description: The large range of time and length scales involved in type Ia supernovae (SN Ia) requires the use of flame models. As a prelude to exploring various options for flame models, we consider, in this paper, high-resolution three-dimensional simulations of the small-scale dynamics of nuclear flames in the supernova environment in which the details of the flame structure are fully resolved. The range of densities examined, 1 to 8 x 107 g cm-3, spans the transition from the laminar flamelet regime to … more
Date: May 27, 2008
Creator: Aspden, Andrew J.; Bell, John B.; Day, Marc S.; Woosley, Stan E. & Zingale, Mike
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Physics of Intrinsic Rotation in Flux-Driven ITG Turbulence

Description: Global, heat flux-driven ITG gyrokinetic simulations which manifest the formation of macroscopic, mean toroidal flow profiles with peak thermal Mach number 0.05, are reported. Both a particle-in-cell (XGC1p) and a semi-Lagrangian (GYSELA) approach are utilized without a priori assumptions of scale-separation between turbulence and mean fields. Flux-driven ITG simulations with different edge flow boundary conditions show in both approaches the development of net unidirectional intrinsic rotation… more
Date: February 23, 2012
Creator: Ku, S.; Dimond, P. H.; Dif-Pradalier, G.; Kwon, J. M.; Sarazin, Y.; Hahm, T. S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simulations of Turbulent Flows with Strong Shocks and Density Variations: Final Report

Description: The target of this SciDAC Science Application was to develop a new capability based on high-order and high-resolution schemes to simulate shock-turbulence interactions and multi-material mixing in planar and spherical geometries, and to study Rayleigh-Taylor and Richtmyer-Meshkov turbulent mixing. These fundamental problems have direct application in high-speed engineering flows, such as inertial confinement fusion (ICF) capsule implosions and scramjet combustion, and also in the natural occurr… more
Date: October 1, 2012
Creator: Lele, Sanjiva
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nonlinear Turbulence Simulations for NSTX H-modes

Description: Present evidence points to remarkably resilient electron temperature profiles in high-density H-mode plasmas on the National Spherical Torus Experiment (NSTX), suggesting that the underlying electron thermal transport mechanisms respond in a highly nonlinear fashion to changes in the gradients. This paper uses measured plasma profiles as input to linear gyrokinetic analysis to identify candidate micro-instabilities that may be responsible for the electron thermal transport. The criteria for use… more
Date: June 22, 2004
Creator: Redi, M. H.; Kaye, S.; Dorland, W.; Bell, R.; Bourdelle, C.; Ethier, S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of Turbulence Decorrelation during Transport Barrier Evolution in a High Temperature Fusion Plasma

Description: A low power polychromatic beam of microwaves is used to diagnose the behavior of turbulent fluctuations in the core of the JT-60U tokamak during the evolution of the internal transport barrier. A continuous reduction in the size of turbulent structures is observed concomitant with the reduction of the density scale length during the evolution of the internal transport barrier. The density correlation length decreases to the order of the ion gyroradius, in contrast to the much longer scale lengt… more
Date: March 29, 2005
Creator: Nazikian, R.; Shinohara, K.; Kramer, G. J.; Valeo, E.; Hill, K.; Hahm, T. S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Strange Attractors in Drift Wave Turbulence

Description: A multi-grid part-in-cell algorithm for a shearless slab drift wave model with kinetic electrons is presented. The algorithm, which is based on an exact separation of adiabatic and nonadiabatic electron responses, is used to investigate the presence of strange attractors in drift wave turbulence. Although the simulation model has a large number of degrees of freedom, it is found that the strange attractor is low-dimensional and that it is strongly affected by dissipative (collisional) effects.
Date: April 25, 2003
Creator: Lewandowski, J.L.V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Inflow Characterization for Marine and Hydrokinetic Energy Devices. FY-2010 Annual Progress Report

Description: Marine and Hydro Kinetic devices (MHK) are being widely studied as a source of renewable energy. The Marrowstone Island site is a potential location for installing MHK devices because the tidal currents observed that are sufficient for power generation. In order to quantify the effects of turbulence on MHK devices and the surrounding environment at this site, a prelimi- nary fluid flow field study was conducted here by the Pacific Northwest National Lab (PNNL) in collaboration with the Applied … more
Date: January 31, 2011
Creator: Richmond, Marshall C.; Durgesh, Vibhav; Thomson, Jim & Polagye, Brian
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Edge, Sol, and Diverter Plasma Turbulence and Macroscopic Transport

Description: In the last few years, it was clearly shown that cross-field transport in the far SOL could be significantly faster than previously thought and that this transport exhibited convective rather then diffusive features. As a result, in high density cases the plasma coming into the SOL from the core recycled at the wall of the tokamak main chamber, rather than flowing into the divertor and recycling there, as the conventional picture of edge plasma flows would suggest. It was also shown that cohere… more
Date: April 25, 2005
Creator: Krasheninnikov, Prof. Sergi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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