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Apparatus for measurements of time and space correlation

Description: The report describes a brief review is made of improvements to an experimental apparatus for time and space correlation designed for study of turbulence. Included is a description of the control of the measurements and a few particular applications.
Date: April 1955
Creator: Favre, Alexandre; Gaviglio, J & Dumas, R
Partner: UNT Libraries Government Documents Department

The Mass Transfer of Single, Solid Uranium Spheres to Flowing Molten Cadmium in Laminar and Turbulent Flow

Description: From Summary and Abstract: "In this study, a 1/2-inch diameter uranium sphere was used and molten cadmium was pumped past the test spheres at different flow rates. Mass transfer coefficients were determined from weight losses of the test spheres."
Date: September 1965
Creator: Traylor, E. Dean
Partner: UNT Libraries Government Documents Department

Convection of a pattern of vorticity through a shock wave

Description: An arbitrary weak spatial distribution of vorticity can be represented in terms of plane sinusoidal shear waves of all orientations and wave lengths (Fourier integral). The analysis treats the passage of a single representative weak shear wave through a plane shock and shows refraction and modification of the shear wave with simultaneous generation of an acoustically intense sound wave. Applications to turbulence and to noise in supersonic wind tunnels are indicated.
Date: September 26, 1952
Creator: Ribner, H. S.
Partner: UNT Libraries Government Documents Department

Measurements of intensity and scale of wind-tunnel turbulence and their relation to the critical Reynolds number of spheres

Description: The investigation of wind-tunnel turbulence, conducted at the National Bureau of Standards with the cooperation of the National Advisory Committee for Aeronautics, has been extended to include a new variable, namely, the scale of the turbulence. This report presents the results of a study of this new variable together with the intensity of the turbulence, and the effect of both on the critical Reynolds number of spheres.
Date: 1937
Creator: Dryden, Hugh L.; Schubauer, G. B.; Mock, W. C., Jr. & Skramstad, H. K.
Partner: UNT Libraries Government Documents Department

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 airfoil shapes in the range of lift coefficients for high-speed and cruising flight."
Date: July 1942
Creator: von Doenhoff, Albert E. & Horton, Elmer A.
Partner: UNT Libraries Government Documents Department

Correlation of data on the statistical theory of turbulence

Description: The statistical theory of turbulence affords an excellent medium for representing the kinematic conditions in turbulent flow and also serves as a valuable aid to exact experimental research. But it is still not developed enough for solving dynamic processes. Even in the simplest case of isotropic turbulence the calculation of the correlation curve or of the decrement of turbulence invariably reaches a point where clear-cut assumptions, such as omission of the inertia terms, or, earlier, mixing length assumptions or even merely general dimensional considerations, must be made.
Date: March 1942
Creator: Wieghardt, K.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

Diffusion of heat from a line source in isotropic turbulence

Description: "An experimental and analytical study has been made of some features of the turbulent heat diffusion behind a line heated wire stretched perpendicular to a flowing isotropic turbulence. The mean temperature distributions have been measured with systematic variations in wind speed, size of turbulence-producing grid, and downstream location of heat source. The nature of the temperature fluctuation field has been studied" (p. 1).
Date: June 5, 1951
Creator: Uberoi, Mahinder S. & Corrsin, Stanley
Partner: UNT Libraries Government Documents Department

Correlations involving pressure fluctuations in homogeneous turbulence

Description: Report presenting an investigation of the correlations of pressure with itself and of pressure with two velocity components for the case of isotropic turbulence. The correlations are expressed in terms of correlations involving two velocity components at a point and two velocity components at another point.
Date: January 1954
Creator: Uberoi, Mahinder S.
Partner: UNT Libraries Government Documents Department

Intensity, scale, and spectra of turbulence in mixing region of free subsonic jet

Description: Report presents the results of the measurements of intensity of turbulence, the longitudinal and lateral correlation coefficients, and the spectra of turbulence in a 3.5-inch-diameter free jet measured with hot-wire anemometers at exit Mach numbers from 0.2 to 0.7 and Reynolds numbers from 192,000 to 725,000.
Date: April 24, 1956
Creator: Laurence, James C.
Partner: UNT Libraries Government Documents Department

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 standard Pitot-static tube were measured in an air stream for several conditions of turbulence. The results may be interpreted as indicating that there is no appreciable effect of turbulence on the vane anemometer and the standard pitot-static tube, but that there is small effect on the drag of a flat plate and the pressure difference between front and rear of a disk" (p. 129).
Date: June 22, 1935
Creator: Schubauer, G. B. & Dryden, H. L.
Partner: UNT Libraries Government Documents Department

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 give the turbulence quantitatively. Another is the definite proof that the discrepancies in the results on the N. P. L. Standard airship models are due mainly to differences in the turbulences of the wind tunnels in which the tests were made.
Date: August 20, 1929
Creator: Dryden, H. L. & Kuethe, A. M.
Partner: UNT Libraries Government Documents Department

Preliminary experimental investigation of low-speed turbulent boundary layers in adverse pressure gradients

Description: Report presenting measurements of velocity profiles and skin friction in subsonic turbulent boundary layers with adverse pressure gradients. The skin friction in an adverse pressure gradient was found to decrease steadily with distance to a value approaching zero for the region of separation. Results regarding the mean velocity distribution and separation, comparison of experimental values with semiempirical relations, and wall shearing stress are provided.
Date: October 1953
Creator: Sandborn, Virgil A.
Partner: UNT Libraries Government Documents Department

Summary of locations, extents, and intensities of turbulent areas encountered during flight investigations of the jet stream from January 7, 1957 to April 28, 1957

Description: "A summary of the locations, extents, and intensities of turbulent areas encountered during a flight investigation of the jet stream is presented. The data were obtained from NACA VGH time-history records" (p. 1).
Date: March 3, 1958
Creator: Copp, Martin R.
Partner: UNT Libraries Government Documents Department

Preliminary investigation of combustion in flowing gas with various turbulence promoters

Description: Report presenting an investigation of combustion occurring downstream of various turbulence promoters in a 20-inch length of a 1 7/8-inch inside-diameter, water-jacketed tubing using premixed vaporized fuel and air. Among the turbulence promoters investigated were flat plates perforated with 1/8-inch diameter holes, 1/4-inch diameter holes, and a single large hole to give 12.4, 17.2, and 21.5 percent open area respectively.
Date: June 7, 1948
Creator: Haddock, Gordon W. & Childs, J. Howard
Partner: UNT Libraries Government Documents Department

Turbulence in the Wake of a Thin Airfoil at Low Speeds

Description: From Summary: "Experiments have been made to determine the nature of turbulence in the wake of a two-dimensional airfoil at low speeds. The experiments were motivated by the need for data which can be used for analysis of the tail-buffeting problem in aircraft design. Turbulent intensity and power spectra of the velocity fluctuations were measured at a Reynolds number of 1.6 x 10(exp 5) for several angles of attack. Total-head measurements were also obtained in an attempt to relate steady and fluctuating wake properties."
Date: January 1957
Creator: Campbell, George S.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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/longitudinal = 36/1) initial turbulence are treated. In either case, turbulence of 0.1 percent longitudinal component generates about 120 dbs of noise.
Date: June 3, 1954
Creator: Ribner, H. S.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

A theory for the lateral response of airplanes to random atmospheric turbulence

Description: Report presenting a derivation of the lateral motions of an airplane flying through continuous random isotropic turbulence in terms of three different functions and sets of forces. Three airplanes of different size are used to demonstrate the method, illustrate characteristic trends, and exhibit some simplifications possible in the calculations.
Date: May 1957
Creator: Eggleston, John M.
Partner: UNT Libraries Government Documents Department

Airspeed fluctuations as a measure of atmospheric turbulence

Description: From Introduction: "Increments in structural loads due to atmospheric turbulence can be accurately expressed in terms of flight speed and effective gust velocities (reference 4). Data from which the effective gust velocities could be computed were also obtained during the flights of the XC-35 airplane. These data have been used to determine the significance of the fluctuations in the pilot's indicated-airspeed readings in relation to structural loads to due to atmospheric turbulence."
Date: July 1945
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

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 consistent answers, further emphasizing a lack of local isotropy" (p. 1).
Date: September 1956
Creator: Sandborn, Virgil A. & Braun, Willis H.
Partner: UNT Libraries Government Documents Department