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Free-stream boundaries of turbulent flows

Description: Report presents the results of an experimental and theoretical study made of the instantaneously sharp and irregular front which is always found to separate turbulent fluid from contiguous "nonturbulent" fluid at a free-stream boundary. This distinct demarcation is known to give an intermittent character to hot-wire signals in the boundary zone. The overall behavior of the front is described statistically in terms of its wrinkle-amplitude growth and its lateral propagation relative to the fluid as functions of downstream coordinate.
Date: 1955
Creator: Corrsin, Stanley & Kistler, Alan L.
Partner: UNT Libraries Government Documents Department

The free-stream boundaries of turbulent flows

Description: Report presenting an experimental and theoretical study of the instantaneously sharp and irregular front that is found to separate turbulent fluid from contiguous "nonturbulent" fluid at a free-stream boundary.
Date: January 1954
Creator: Corrsin, Stanley & Kistler, Alan L.
Partner: UNT Libraries Government Documents Department

Note on the calculation of boundary layers

Description: The properties of the solutions of the hydrodynamic equations of viscous fluid by "boundary-layer omission" are discussed. A method is indicated for the numerical determination of the solution for a known initial profile u(x(sub o),y) and pressure distribution p(x) within the region.
Date: November 1940
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department

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

Air flow in the boundary layer near a plate

Description: From Summary: "The published data on the distribution of speed near a thin flat plate with sharp leading edge placed parallel to the flow (skin friction plate) are reviewed and the results of some additional measurements are described. The purpose of the experiments was to study the basic phenomena of boundary-layer flow under simple conditions."
Date: March 1936
Creator: Dryden, Hugh L.
Partner: UNT Libraries Government Documents Department

Air flow in a separating laminar boundary layer

Description: Report discussing the speed distribution in a laminar boundary layer on the surface of an elliptic cylinder, of major and minor axes 11.78 and 3.98 inches, respectively, has been determined by means of a hot-wire anemometer. The direction of the impinging air stream was parallel to the major axis. Special attention was given to the region of separation and to the exact location of the point of separation. An approximate method, developed by K. Pohlhausen for computing the speed distribution, the thickness of the layer, and the point of separation, is described in detail; and speed-distribution curves calculated by this method are presented for comparison with experiment.
Date: December 1, 1934
Creator: Schubauer, G. B.
Partner: UNT Libraries Government Documents Department

An analytical investigation of the effect of the rate of increase of turbulent kinetic energy in the stream direction on the development of turbulent boundary layers in adverse pressure gradients

Description: From Introduction: "The purpose of this paper is to provide a derivation of the general integral form of the boundary equation without neglecting the Reynolds normal-stress term. Two special cases of this equation are given explicitly."
Date: November 1, 1953
Creator: Rashis, Bernard
Partner: UNT Libraries Government Documents Department

Analytical investigation of flow and heat transfer in coolant passages of free-convection liquid-cooled turbines

Description: From Introduction: "An analytical investigation of the problems arising in connection with this cooling method was conducted at the NACA Lewis laboratory and is presented herein. This analysis investigates: (1) the smallest diameter hole that can be made without endangering the circulation of the liquid, and (2) methods of improving the circulation in a small-diameter hole."
Date: July 18, 1950
Creator: Eckert, E. R. G. & Jackson, Thomas W.
Partner: UNT Libraries Government Documents Department

Analysis of laminar forced-convection heat transfer in entrance region of flat rectangular ducts

Description: From Introduction: "Beyond the position where the boundary layer treatment can no longer be used, curves have been faired to connect the Nusselt number results of the present analysis with those of reference 3, in which a parabolic velocity profile is assumed throughout the entire duct length. So that a comparison could be made with the results of reference 3, the boundary layer analysis was used to study the development of the temperature profile associated with a parabolic velocity profile throughout."
Date: January 1955
Creator: Sparrow, E M
Partner: UNT Libraries Government Documents Department

Experiments with an airfoil from which the boundary layer is removed by suction

Description: Our attempts to improve the properties of airfoils by removing the boundary layer by suction, go back to 1922. The object of the suction is chiefly to prevent the detachment of the boundary layer from the surface of the airfoil. At large angles of attack, such detachment prevents the attainment of the great lift promised by the theory, besides greatly increasing the drag, especially of thick airfoils. This report gives results of those experiments.
Date: August 1926
Creator: Ackeret, J.; Betz, A. & Schrenk, O.
Partner: UNT Libraries Government Documents Department

Shape of initial portion of boundary of supersonic axisymmetric free jets at large jet pressure ratios

Description: Calculations have been made of the initial portion of the boundary of axisymmetric free jets exhausting at large pressure ratios from a conically divergent nozzle having a jet exit Mach number of 2.5 and a semidivergence angle of 15 degrees. The results of the calculations indicate the size and shape of the jet to be expected at large pressure ratios, the effects of ratio of specific heats, and the large initial inclinations of the boundary that are likely to be encountered by hypersonic vehicles at high altitude.
Date: January 1958
Creator: Love, Eugene S. & Lee, Louise P.
Partner: UNT Libraries Government Documents Department

An integral solution to the flat-plate laminar boundary-layer flow existing inside and after expansion waves and after shock waves moving into quiescent fluid with particular application to the complete shock-tube flow

Description: Report presenting a solution to the unsteady two-dimensional laminar boundary-layer flow inside centered expansion waves and behind both centered expansion waves and shock waves using an extension of the Karman-Pohlhausen method. The Prandtl unsteady-boundary-layer equations are also integrated normal to the surface bounding the flow and are transformed into a conical coordinate system. The solution to the two-dimensional unsteady laminar boundary layer existing at all points in an air-air shock tube is obtained using the method.
Date: June 1957
Creator: Trimpi, Robert L. & Cohen, Nathaniel B.
Partner: UNT Libraries Government Documents Department

Boundary Layer

Description: From Introduction: "The fundamental, practically the most important branch of the modern mechanics of a viscous fluid or a gas, is that branch which concerns itself with the study of the boundary layer. The presence of a boundary layer accounts for the origin of the resistance and lift force, the breakdown of the smooth flow about bodies, and other phenomena that are associated with the motion of a body in a real fluid. The concept of boundary layer was clearly formulated by the founder of aerodynamics, N. E. Joukowsky, in his well-known work "On the Form of Ships" published as early as 1890."
Date: May 1956
Creator: Loitsianskii, L. G.
Partner: UNT Libraries Government Documents Department

Tables of exact laminar-boundary-layer solutions when the wall is porous and fluid properties are variable

Description: Report presenting the three partial differential equations of the laminar boundary layer for two-dimensional steady-state compressible flow, which have been transformed into two ordinary differential equations by the method of Pohlhausen, Falkner, and Skan. A total of 58 cases have been solved numerically by the method of Picard. For each of the cases, the displacement, momentum, and convection thicknesses, as well as Nusselt number and coefficient of friction at the wall, were computed.
Date: September 1951
Creator: Brown, W. Byron & Donoughe, Patrick L.
Partner: UNT Libraries Government Documents Department

Analytic determination of the discharge coefficients of flow nozzles

Description: From Introduction: "In rounded-approach nozzles with discharge coefficients close to unity, the frictional effects are concentrated in the boundary layer. A method of obtaining an analytical relation among the discharge coefficient, Reynolds number, and the nozzle geometry by utilization of elementary boundary-layer theory is presented herein."
Date: April 1955
Creator: Simmons, Frederick S.
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

Analysis and calculation by integral methods of laminar compressible boundary-layer with heat transfer and with and without pressure gradient

Description: From Introduction: "The purpose of the present report is to present a comprehensive summary of theoretical investigations of comprehensible laminar boundary layers which have been carried out since 1949 at the Polytechnic Institute of Brooklyn under the sponsorship and with the financial assistance of the National Advisory Committee for Aeronautics. The results of these investigations are contained primarily in references 1 to 7."
Date: April 12, 1955
Creator: Morduchow, Morris
Partner: UNT Libraries Government Documents Department

Application of supersonic vortex-flow theory to the design of supersonic impulse compressor- or turbine-blade sections

Description: From Introduction: "The purpose of this paper is to present an analytical method for the design of two-dimensional related selection of a blade for particular rotor conditions may be made quickly and easily and its performance deduced from tests of representative sections in cascade."
Date: April 24, 1952
Creator: Boxer, Emanuel; Sterrett, James R. & Wlodarski, John
Partner: UNT Libraries Government Documents Department

An investigation of supersonic turbulent boundary layers on slender bodies of revolution in free flight by use of a Mach-Zehnder interferometer and shadowgraphs

Description: Report presenting a study of slender bodies of revolution in free flight at Mach numbers 3.2 and 3.6, which were photographed and analyzed to obtain the turbulent-boundary-layer density distributions for the case of a body surface that is cold compared to recovery temperature. Results regarding density profiles, density distributions, comparison with the Crocco equation, calculation of the heat-transfer rate, and observations of the turbulent-boundary-layer image structure from shadowgraphs, and relation the interferometer results are provided.
Date: September 1958
Creator: Seiff, Alvin & Short, Barbara J.
Partner: UNT Libraries Government Documents Department

Analysis of particle motions for a class of three-dimensional incompressible laminar boundary layers

Description: From Introduction: "Results obtained in the experimental investigations of secondary flows in turbomachines (refs. 1 to 3) indicate that information concerning three-dimensional laminar boundary-layer behavior can be of practical value in interpreting and correlating measurements of losses in the turbo-machines for design purposes. Reference 4 gives a theoretical analysis of the overturning (more than mainstream turning) of the three-dimensional laminar boundary layer developed on flat or nearly flat surfaces, under mainstream flows which consist of streamline translates (i.e., the entire streamline pattern can be obtained by translating any particular streamline pattern can be obtained by translating any particular streamline parallel to the leading edge, fig. 1) with constant axial velocity component."
Date: November 1956
Creator: Hansen, Arthur G. & Herzig, Howard Z.
Partner: UNT Libraries Government Documents Department