36 Matching Results

Search Results

Advanced search parameters have been applied.

On the turbulent friction layer for rising pressure

Description: Among the information presented are included displacement, momentum, and kinetic energy thicknesses, shearing stress distributions across boundary layer, and surface friction coefficients. The Gruschwitz method and its modifications are examined and tested. An energy theorem for the turbulent boundary layer is introduced and discussed but does not lead to a method for the prediction of the behavior of the turbulent boundary layer because relations for the shearing stress and the surface friction are lacking.
Date: October 1951
Creator: Wieghardt, K. & Tillmann, W.
Partner: UNT Libraries Government Documents Department

Determination of general relations for the behavior of turbulent boundary layers

Description: From Summary: "An analysis has been made of a considerable amount of data for turbulent boundary layers along wings and bodies of various shapes in order to determine the fundamental variables that control the development of turbulent boundary layers. It was found that the type of velocity distribution in the boundary layer could be expressed in terms of a single parameter. This parameter was chosen as the ratio of the displacement thickness to the momentum thickness of the boundary layer. The variables that control the development of the turbulent boundary layer apparently are: (1) the ratio of the nondimensional pressure gradient, expressed in terms of the local dynamic pressure outside the boundary layer and boundary-layer thickness, to the local skin-friction coefficient and (2) the shape of the boundary layer. An empirical equation has been developed in terms of these variables that, when used with the momentum equation and the skin-friction relation, makes it possible to trace the development of the turbulent boundary layer to the separation point."
Date: April 13, 1943
Creator: von Doenhoff, Albert E. & Tetervin, Neal
Partner: UNT Libraries Government Documents Department

An evaluation of four experimental methods for measuring mean properties of a supersonic turbulent boundary layer

Description: Report presenting surveys made through a turbulent boundary layer on a flat plate by means of a pitot probe, an X-ray densitometer, and hot-wire and cold-wire probes. Results were analyzed to determine the reliability of basic data and how well the distributions of properties in the boundary layer compare with those assumed in theoretical analyses.
Date: June 1956
Creator: Nothwang, George J.
Partner: UNT Libraries Government Documents Department

An evaluation of four experimental methods for measuring mean properties of a supersonic turbulent boundary layer

Description: From Summary: "Surveys were made through a turbulent boundary layer on a flat plate by means of a pitot probe, an x-ray densitometer, and hot-wire and cold-wire probes. Results from these surveys were analyzed to determine (a) the reliability of the basic data and hence the methods by which they were obtained, and (b) how well the actual distributions of properties in the boundary layer compare with those commonly assumed in semiempirical and theoretical analyses. All surveys were made at the same longitudinal station on the flat plate. The tests were conducted in a an 8- by 8-inch supersonic nozzle. The free-stream Mach number was 3.03 and the Reynolds number was approximately 210,000 based on boundary-layer thickness."
Date: April 19, 1956
Creator: Nothwang, George J.
Partner: UNT Libraries Government Documents Department

An experimental study of the turbulent boundary layer on a shock-tube wall

Description: From Summary: "Interferometric measurements were made of the density profiles of an unsteady turbulent boundary layer on the flat wall of a shock tube. The investigation included both subsonic and supersonic flow (Mach numbers of 0.50 and 1.77) with no pressure gradient and with heat transfer to a cold wall. Velocity profiles and average skin-friction coefficients were calculated. Effects on the velocity profile of surface roughness and flow lengths are examined."
Date: June 1958
Creator: Gooderum, Paul B.
Partner: UNT Libraries Government Documents Department

Turbulent Boundary Layer of an Airfoil

Description: A need has arisen for a new determination of the velocity profiles in the boundary layer. Assuming that the character of the velocity distribution depends to a large extent on the character of the shear distribution across the boundary layer, we shall consider the nature of the shear distribution for a boundary layer with a pressure gradient.
Date: April 1937
Creator: Fediaevsky, K.
Partner: UNT Libraries Government Documents Department

Skin Friction of Incompressible Turbulent Boundary Layer Under Adverse Pressure Gradients

Description: Note presenting experimental data for skin friction of turbulent boundary layers under adverse pressure gradients from several sources in graphical form. Data obtained by the momentum-balance method are shown to follow a trend opposite to that of data obtained by hot-wire and heat-transfer methods.
Date: August 1951
Creator: Goldschmied, Fabio R.
Partner: UNT Libraries Government Documents Department

Determination of General Relations for the Behavior of Turbulent Boundary Layers

Description: Report presenting an analysis of data for turbulent boundary layers along wings and bodies of various shapes in order to determine the fundamental variables that control the development of turbulent boundary layers. Results indicate that the type of velocity distribution in the boundary layer could be expressed in terms of a single parameter.
Date: July 1943
Creator: von Doenhoff, Albert E. & Tetervin, Neal
Partner: UNT Libraries Government Documents Department

A Comparison of the Turbulent Boundary-Layer Growth on an Unswept and a Swept Wing

Description: Note presenting an experimental investigation in which measurements were made of the turbulent boundary layer of a two-dimensional unswept wing and a comparable wing swept 45 degrees. The results indicate the applicability of simple sweep theory for determining turbulent boundary-layer growth on the swept wing for a lift coefficient of zero.
Date: September 1951
Creator: Altman, John M. & Hayter, Nora-Lee F.
Partner: UNT Libraries Government Documents Department

Wall Pressure Fluctuations in a Turbulent Boundary Layer

Description: Note presenting an investigation of sound generation that is generated by turbulence on a solid surface. Suitable equipment has been developed to measure the fluctuating wall pressure in the turbulent boundary layer. Results regarding the response of the transducer in a laminar and turbulent boundary layer, power-spectrum measurements, and mean-square pressure measurements are provided.
Date: March 1958
Creator: Willmarth, William W.
Partner: UNT Libraries Government Documents Department

Studies of Von Kármán's Similarity Theory and Its Extension to Compressible Flows: A Similarity Theory for Turbulent Boundary Layer Over a Flat Plate in Compressible Flow

Description: Note presenting a treatment of the problem of turbulent boundary layer over a flat plate in compressible flow. The dissipation term in the energy equation, often neglected, is first carefully studied and found to be of importance. The four main approximations include the turbulence pattern, the boundary-layer growth, the two choices of the length scale, and the effect of pressure gradient.
Date: November 1951
Creator: Lin, C. C. & Shen, S. F.
Partner: UNT Libraries Government Documents Department

Studies of Von Kármán's Similarity Theory and Its Extension to Compressible Flow: Investigation of Turbulent Boundary Layer Over a Flat Plate in Compressible Flow by the Similarity Theory

Description: Note presenting an investigation of the turbulent-boundary-layer flow over a flat plate in compressible flow. The report shows how the influence of the Mach number can be predicted from the theory after the constant coefficients in the theory are determined by one set of experimental measurements. By averaging the Navier-Stokes equations, differential equations for the mean flow are obtained.
Date: November 1951
Creator: Shen, S. F.
Partner: UNT Libraries Government Documents Department

Universal Logarithmic Law of Velocity Distribution as Applied to the Investigation of Boundary Layer and Drag of Streamline Bodies at Large Reynolds Number

Description: In the present paper we shall consider a figure of revolution, so that the formulas applicable to the more simple cases as, for example, a wing or flat plate will follow from our equations as corollaries. For checking the results of our theory, we made use of the data derived from the tests of Freeman on a 1/40-scale model of the airship "Akron" conducted in the large NACA wind tunnel. In the first part we shall derive the fundamental equation for a body of revolution according to the Karman theory in its original form, and in the second part we shall give all the comparisons of the results of tests with the modified theory.
Date: November 1937
Creator: Gurjienko, G.
Partner: UNT Libraries Government Documents Department

Light Diffusion Through High-Speed Turbulent Boundary Layers

Description: Memorandum presenting the optical transmission characteristics of turbulent boundary layers in air on a flat plate with negligible heat transfer measured photometrically for ranges of Mach number from 0.4 to 2.5. The results indicated that the scattering from a collimated beam of white light which penetrates a turbulent boundary layer depends mainly on the integral across the layer of the difference between the free-stream density and the local boundary-layer density.
Date: May 26, 1956
Creator: Stine, Howard A. & Winovich, Warren
Partner: UNT Libraries Government Documents Department

A Procedure for Calculating the Development of Turbulent Boundary Layers Under the Influence of Adverse Pressure Gradients

Description: Note presenting a procedure based on the kinetic-energy equation and an extended form of the momentum equation that has been devised for calculating the development of turbulent boundary layers, in adverse pressure gradients, for that class of flows for which the fluid density in all points and total pressure outside the boundary layer are invariant. Results regarding two-dimensional flow, conical-diffuser flow, separation, and the application of the procedure are provided.
Date: September 1951
Creator: Rubert, Kennedy F. & Persh, Jerome
Partner: UNT Libraries Government Documents Department

Approximate Calculation of Turbulent Boundary-Layer Development in Compressible Flow

Description: Note presenting numerical solutions of quantities appearing in the Karman momentum equation for the development of a turbulent boundary layer in plane and in radial compressible flows along thermally insulted surfaces in tabular form for a rnage of Mach numbers from 0.100 to 10. Through use of the tables, approximate calculation of boundary-layer growth is reduced to routine arithmetic computation.
Date: April 1951
Creator: Tucker, Maurice
Partner: UNT Libraries Government Documents Department

Approximate Formulas for the Computation of Turbulent Boundary-Layer Momentum Thicknesses in Compressible Flows

Description: Report presenting approximate formulas for the computation of the momentum thickness of turbulent boundary layers on two-dimensional bodies, on bodies of revolution at zero angle of attack, and on the inner surfaces of round channels all in compressible flow given in the form of integrals that can be conveniently computed. Results for skin-friction formulas, laminar boundary layers, and full thickness of boundary layer are provided.
Date: March 1946
Creator: Tetervin, Neal
Partner: UNT Libraries Government Documents Department

Experimental Investigation of the Turbulent-Boundary-Layer Temperature-Recovery Factor on Bodies of Revolution at Mach Numbers From 2.0 to 3.8

Description: Note presenting measurements of the local temperature-recovery factor of a turbulent boundary layer produced by natural transition on a thin-walled, metal, 10 degree cone measured at a range of Mach and Reynolds numbers. The recovery factor in the fully developed turbulent zone was found to have a value of 0.0882 which was essentially independent of both Mach number and Reynolds number. Results regarding the 10 degree cone and 40 degree cone cylinder are provided.
Date: March 1952
Creator: Stine, Howard A. & Scherrer, Richard
Partner: UNT Libraries Government Documents Department

Some Features of Artificially Thickened Fully Developed Turbulent Boundary Layers with Zero Pressure Gradient

Description: Report gives an account of an investigation conducted to determine the feasibility of artificially thickening a turbulent boundary layer on a flat plate. A description is given of several methods used to thicken artificially the boundary layer. It is shown that it is possible to do substantial thickening and obtain a fully developed turbulent boundary layer, which is free from any distortions introduced by the thickening process, and, as such, is a suitable medium for fundamental research.
Date: September 15, 1950
Creator: Klebanoff, P. S. & Diehl, Z. W.
Partner: UNT Libraries Government Documents Department

On the Contribution of Turbulent Boundary Layers to the Noise Inside a Fuselage

Description: "The following report deals in preliminary fashion with the transmission through a fuselage of random noise generated on the fuselage skin by a turbulent boundary layer. The concept of attenuation is abandoned and instead the problem is formulated as a sequence of two linear couplings: the turbulent boundary layer fluctuations excite the fuselage skin in lateral vibrations and the skin vibrations induce sound inside the fuselage. The techniques used are those required to determine the response of linear systems to random forcing functions of several variables" (p. 1).
Date: December 1956
Creator: Corcos, G. M. & Liepmann, H. W.
Partner: UNT Libraries Government Documents Department

Schlieren investigation of the wing shock-wave boundary-layer interaction in flight

Description: Report presenting data obtained in flight using a schileren apparatus that photographed the shock-wave interaction with a thick turbulent boundary layer on a wing. Local Mach number and boundary-layer characteristics obtained from pressure measurements in the vicinity of the shock wave are also presented.
Date: September 19, 1951
Creator: Cooper, George E. & Bray, Richard S.
Partner: UNT Libraries Government Documents Department

The Influence of Surface Injection on Heat-Transfer and Skin Friction Associated With the High-Speed Turbulent Boundary Layer

Description: Memorandum presenting a correlation of analyses of the effect of distributed surface injection on the heat transfer and skin friction associated with the turbulent boundary layer at high speeds to eliminate the effects of Mach and Reynolds number. Data for heat transfer and skin friction at three Mach numbers are compared with the analyses and the agreement is good.
Date: February 20, 1956
Creator: Rubesin, Morris W.
Partner: UNT Libraries Government Documents Department

A Modified Reynolds Analogy for the Compressible Turbulent Boundary Layer on a Flat Plate

Description: Note presenting a modified Reynolds analogy developed for the compressible turbulent boundary layer on a flat plate. When mixing-length theories are used to evaluate terms of the final expressions, it is found for air that the ratio of Stanton number to half the local skin-friction coefficient is greater than unity.
Date: March 1953
Creator: Rubesin, Morris W.
Partner: UNT Libraries Government Documents Department

An Analytical and Experimental Investigation of the Skin Friction of the Turbulent Boundary Layer on a Flat Plate at Supersonic Speeds

Description: Report presenting a review of turbulent-boundary-layer analyses and experimental data for average skin-friction coefficients on a flat plate in high-speed flow. New solutions are presented which show the effect of using a continuous velocity gradient and the effect of the extent of the laminar sublayer on the average skin-friction coefficient.
Date: February 1951
Creator: Rubesin, Morris W.; Maydew, Randall C. & Varga, Steven A.
Partner: UNT Libraries Government Documents Department