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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

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

Effect of thermal properties on laminar-boundary-layer characteristics

Description: Report presenting an iteration method for solving the laminar-boundary-layer equations for compressible flow in the absence of a pressure gradient when the temperature variation of all the fluid thermal properties is considered. Results in regard to skin friction and heat-transfer characteristics are provided.
Date: March 1953
Creator: Klunker, E. B. & McLean, F. Edward
Partner: UNT Libraries Government Documents Department

Simplified method for calculation of compressible laminar boundary with arbitrary free-stream pressure gradient

Description: Report presenting a simplification of the Karman-Polhausen integral method as applied to compressible laminar boundary layers. The analysis was conducted under the assumptions of a Prandtl number of 1, zero heat transfer, and a linear viscosity-temperature relation.
Date: October 1951
Creator: Low, George M.
Partner: UNT Libraries Government Documents Department

On the Three-Dimensional Instability of Laminar Boundary Layers on Concave Walls

Description: Memorandum presenting a study of the stability of laminar boundary layer profiles on slightly curved walls relative to small disturbances, in the shape of vortices, whose axes are parallel to the principal direction of flow. The result in an eigenvalue problem by which, for a given undisturbed flow at a prescribed wall, the amplification or decay is computed for each Reynolds number and each vortex thickness.
Date: June 1954
Creator: Göertler, H.
Partner: UNT Libraries Government Documents Department

Interferometer corrections and measurements of laminar boundary layers in supersonic stream

Description: Report presenting an investigation of the laminar boundary layer on a flat plate in a supersonic stream by means of a Zehnder-Mach interferometer and a total-pressure probe. Results regarding the velocity and density profiles, skin friction, and recovery factor are provided.
Date: June 1950
Creator: Blue, Robert E.
Partner: UNT Libraries Government Documents Department

Some Recent Contributions to the Study of Transition and Turbulent Boundary Layers

Description: Report presenting a paper in two parts about transition and turbulent boundary layers. The first part reviews the current problem of the instability of laminar boundary layers. The second part reviews the current state of knowledge of the mechanics of turbulent boundary layers and of the methods now being used for fundamental studies of the turbulent fluctuations in turbulent boundary layers.
Date: April 1947
Creator: Dryden, Hugh L.
Partner: UNT Libraries Government Documents Department

Computation of the two-dimensional flow in a laminar boundary layer

Description: A comparison is made of the boundary-layer flow computed by the approximate method developed by K. Pohlhausen with the exact solutions which have been published for several special cases. A modification of Pohlhausen's method has been developed which extends the range of application at the expense of some decrease in the accuracy of the approximations.
Date: May 1934
Creator: Dryden, Hugh L.
Partner: UNT Libraries Government Documents Department

Solutions of laminar-boundary-equations which result in specific-weight-flow profiles locally exceeding free-stream values

Description: Revised solutions of the laminar-boundary-layer equations for cases which involved cooling at the wall combined with large pressure gradients in the main stream produced specific-weight-flow profiles which locally exceeded free-stream values. Heat-transfer and friction coefficients, boundary-layer thicknesses, and velocity, temperature, and specific-weight-flow distributions resulting from the revised solutions are presented for Euler numbers of 0.5 and 1, stream-to-wall temperature ratios of 2 and 4, and cooling-air flow rates through porous walls designated by flow parameters of 0, -0.5, and -1.
Date: September 1952
Creator: Brown, W. Byron & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

The Effect of Compressibility on the Growth of the Laminar Boundary Layer on Low-Drag Wings and Bodies

Description: Report presenting a consideration of the development of the laminar boundary layer in a compressible fluid. Formulas are given for determining the boundary-layer thickness and the boundary-layer Reynolds number, which is a measure of the boundary-layer stability, for airfoils and bodies of revolution.
Date: July 1947
Creator: Allen, Julian & Nitzberg, Gerald E.
Partner: UNT Libraries Government Documents Department

Method for calculation of compressible laminar boundary layer with axial pressure gradient and heat transfer

Description: Report presenting a rapid and sufficiently accurate method of determining laminar-boundary-layer characteristics in flow with a given free-stream Mach number and given velocity distribution at the edge of the boundary layer. The method can be easily applied to flow with zero pressure gradient for any constant Prandtl number of the order of unity and any given temperature distribution along wall.
Date: January 1954
Creator: Libby, Paul A. & Morduchow, Morris
Partner: UNT Libraries Government Documents Department

Heat transfer at the forward stagnation point of blunt bodies

Description: Report presenting relations for the calculation of heat transfer at the forward stagnation point of both two-dimensional and axially symmetric blunt bodies. The relations for the heat transfer, which were obtained from exact solutions to the equations of the laminar boundary layer, are presented in terms of local velocity gradient at the stagnation point.
Date: July 1955
Creator: Reshotko, Eli & Cohen, Clarence B.
Partner: UNT Libraries Government Documents Department

On possible similarity solutions for three-dimensional incompressible laminar boundary layers 1: similarity with respect to stationary rectangular coordinates

Description: From Summary: "Solutions of mainstream flow patterns for all possible incompressible laminar-boundary-layer flows having classical similarity with respect to rectangular coordinate systems are derived. These solutions, which apply to a wide range of flows, are summarized in table form."
Date: October 1956
Creator: Hansen, Arthur G. & Herzig, Howard Z.
Partner: UNT Libraries Government Documents Department

An approximate method for determining the displacement effects and viscous drag of laminar boundary layers in two-dimensional hypersonic flow

Description: From Summary: "A simplified approximate theory is presented by means of which the laminar boundary layer over an insulated two-dimensional surface may be calculated, a linear velocity profile being assumed, and an estimate made of its effect in changing the pressure distribution over the profile upon which the boundary layer is formed. Skin friction is also determined. Comparisons of results from this theory are made with experimental results at a Mach number of 6.86 and a Reynolds number of 980,000."
Date: September 1952
Creator: Bertram, Mitchel H.
Partner: UNT Libraries Government Documents Department

A rapid method for estimating the separation point of a compressible laminar boundary layer

Description: Report presenting a method for quickly estimating the separation point of a laminar boundary layer in a compressible flow. The method should be usable for any two-dimensional flow in which classical boundary-layer assumptions are satisfied. Results obtained from a variety of calculations indicate that for all velocity gradients, the amount of velocity recovery possible before laminar separation occurs decreases as Mach number increases.
Date: February 1953
Creator: Loftin, Laurence K., Jr. & Wilson, Homer B., Jr.
Partner: UNT Libraries Government Documents Department

The compressible laminar boundary layer with heat transfer and small pressure gradient

Description: Report presenting a perturbation method for the calculation of velocity and temperature profiles and skin-friction and heat-transfer characteristics for two-dimensional, compressible laminar boundary layers with heat transfer and a small arbitrary pressure gradient is presented. The combined effects of heat transfer and pressure gradient on boundary-layer characteristics are demonstrated by applying the results of the analysis to two representative wings.
Date: October 1953
Creator: Low, George M.
Partner: UNT Libraries Government Documents Department

Cooling requirements for stability of laminar boundary layer with small pressure gradient at supersonic speeds

Description: Report presenting the amount of cooling required to stabilize the two-dimensional supersonic laminar boundary layer for all Reynolds numbers for flows with pressure gradients of a magnitude usually encountered over slender aerodynamic shapes. It is determined that small pressure gradients have an appreciable effect on stability.
Date: March 1954
Creator: Low, George M.
Partner: UNT Libraries Government Documents Department

Laminar Boundary Layer on a Circular Cone in Supersonic Flow at a Small Angle of Attack

Description: Note presenting an analysis of the laminar boundary layer on a circular cone at angle of attack to a supersonic stream. A solution for the outer nonviscous flow, as obtained by a method of perturbation in angle of attack, is available and is presumed to govern the development of the boundary layer, subject to certain restrictions and corrections.
Date: October 1951
Creator: Moore, Franklin K.
Partner: UNT Libraries Government Documents Department

Simplified Method for Determination of Critical Height of Distributed Roughness Particles for Boundary-Layer Transition at Mach Numbers From 0 to 5

Description: Note presenting a simplified method for determination of the critical height of three-dimensional roughness particles required to promote premature transition of a laminar boundary layer on models of airplanes or airplane components in a wind tunnel with zero heat transfer. The method has been applied to various types of configurations in several wind-tunnel investigations.
Date: September 1958
Creator: Braslow, Albert L. & Knox, Eugene C.
Partner: UNT Libraries Government Documents Department

A Simple Numerical Method for the Calculation of the Laminar Boundary Layer

Description: An iteration difference method for the calculation of the incompressible laminar boundary layer is described. The method uses Prandtl's boundary layer equation and the boundary conditions directly and permits the attainment of an arbitrary accuracy. The method has been tested successfully in the continuation of the Blasius profile on the flat plate, on the circular cylinder investigated by Heimenz and on an elliptical cylinder of fineness ratio 1:4. The method makes possible the testing of previously developed methods, all of which contain important assumptions.
Date: April 1952
Creator: Schröder, K.
Partner: UNT Libraries Government Documents Department

Remarks Concerning the Behavior of the Laminar Boundary Layer in Compressible Flows

Description: Note presenting the boundary-layer equation of motion and the boundary-layer energy equation for the compressible and steady laminar boundary layer on two-dimensional bodies and bodies of revolution in a nondimensional form and to provide a clearer indication of the effects of Mach number, Reynolds number, and the properties of the gas.
Date: January 1949
Creator: Tetervin, Neal
Partner: UNT Libraries Government Documents Department

Exploratory Investigation of Laminar-Boundary-Layer Oscillations on a Rotating Disk

Description: Sinusoidal waves excited by random disturbances have been observed in the laminar boundary layer of a rotating disk at Reynolds numbers in a narrow range below the Reynolds number of transition. Their frequency was found to be approximately a constant times the velocity of the disk. The velocity of the waves at the radius of 11 inches was determined and found to be 0.2 linear velocity of the disk in a downstream direction, making an angle of approximately 14 degrees with the outward drawn radius vector.
Date: May 1947
Creator: Smith, Newell H.
Partner: UNT Libraries Government Documents Department