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A Low-Speed Experimental Investigation of the Effect of a Sandpaper Type of Roughness on Boundary-Layer Transition

Description: Report describing the effects of an area of roughness on the velocity and turbulence measurements of an airfoil. It details the effects of the size, location, and height of the roughness on the Reynolds number. From Summary: "An investigation was made in the Langley low-turbulence pressure tunnel to determine the effect of size and location of a sandpaper type of roughness on the Reynolds number for transition."
Date: 1958
Creator: Horton, Elmer A. & von Doenhoff, Albert E.
Partner: UNT Libraries Government Documents Department
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Icing-Protection Requirements for Reciprocating-Engine Induction Systems

Description: Report presenting an investigation of the icing of aircraft-engine induction systems. Criterions for safe operation and for the design of new induction system are established through the investigation. The results were obtained from laboratory investigations of carburetor-supercharger combinations, wind-tunnel investigations of air scoops, multicylinder-engine studies, and flight investigations.
Date: 1950
Creator: Coles, Willard D.; Rollin, Vern G. & Mulholland, Donald R.
Partner: UNT Libraries Government Documents Department
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Comparison of High-Speed Operating Characteristics of Size 215 Cylindrical-Roller Bearings as Determined in Turbojet Engine and in Laboratory Test Rig

Description: A comparison of the operating characteristics of 75-millimeter-bore (size 215) cylindrical-roller one-piece inner-race-riding cage-type bearings was made by means of a laboratory test rig and a turbojet engine. Cooling correlation parameters were determined by means of dimensional analysis, and the generalized results for both the inner- and the outer-race bearing operating temperatures are computed for the laboratory test rig and the turbojet engine. A method is given that enables the designer… more
Date: 1952
Creator: Macks, E. Fred & Nemeth, Zolton N.
Partner: UNT Libraries Government Documents Department
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Theoretical and analog studies of the effects of nonlinear stability derivatives on the longitudinal motions of an aircraft in response to step control deflections and to the influence of proportional automatic control

Description: Through theoretical and analog results the effects of two nonlinear stability derivatives on the longitudinal motions of an aircraft have been investigated. Nonlinear functions of pitching-moment and lift coefficients with angle of attack were considered. Analog results of aircraft motions in response to step elevator deflections and to the action of the proportional control systems are presented. The occurrence of continuous hunting oscillations was predicted and demonstrated for the attitude … more
Date: December 29, 1950
Creator: Curfman, Howard J., Jr.
Partner: UNT Libraries Government Documents Department
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Transonic Flow Past Cone Cylinders

Description: "Experimental results are presented for transonic flow post cone-cylinder, axially symmetric bodies. The drag coefficient and surface Mach number are studied as the free-stream Mach number is varied and, wherever possible, the experimental results are compared with theoretical predictions. Interferometric results for several typical flow configurations are shown and an example of shock-free supersonic-to-subsonic compression is experimentally demonstrated" (p. 963).
Date: April 15, 1953
Creator: Solomon, George E.
Partner: UNT Libraries Government Documents Department
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A unified two-dimensional approach to the calculation of three-dimensional hypersonic flows, with application to bodies of revolution

Description: A procedure for calculating three-dimensional steady and nonsteady supersonic flows with the method of characteristics is developed and discussed. An approximate method is deduced from the characteristics method and shown to be of practical value at high supersonic speeds.
Date: August 15, 1952
Creator: Eggers, A. J., Jr. & Savin, Raymond C.
Partner: UNT Libraries Government Documents Department
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High-Resolution Autoradiography

Description: This investigation was made to adapt wet-process autoradiography to metallurgical samples to obtain high resolution of segregated radioactive elements in microstructures. Results are confined to development of the technique, which was perfected to a resolution of less than 10 microns. The radioactive samples included carbon-14 carburized iron and steel, nickel-63 electroplated samples, a powder product containing nickel-63, and tungsten-185 in N-155 alloy.
Date: June 1, 1953
Creator: Towe, George C.; Gomberg, Henry J. & Freemen, J. W.
Partner: UNT Libraries Government Documents Department
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Quasi-Cylindrical Theory of Wing-Body Interference at Supersonic Speeds and Comparison with Experiment

Description: "A theoretical method is presented for calculating the flow field about wing-body combinations employing bodies deviating only slightly in shape from a circular cylinder. The method is applied to the calculation of the pressure field acting between a circular cylindrical body and a rectangular wing. The case of zero body angle of attack and variable wing incidence is considered as well as the case of zero wing incidence and variable body angle of attack" (p. 1299).
Date: January 4, 1954
Creator: Nielsen, Jack N.
Partner: UNT Libraries Government Documents Department
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A theory for stability and buzz pulsation amplitude in ram jets and an experimental investigation including scale effects

Description: From a theory developed on a quasi-one-dimensional-flow basis, it is found that the stability of the ram jet is dependent upon the instantaneous values of mass flow and total pressure recovery of the supersonic diffuser and immediate neighboring subsonic diffuser. Conditions for stable and unstable flow are presented. The theory developed in the report is in agreement with the experimental data of NACA-TN-3506 and NACA-RM-L50K30. A simple theory for predicting the approximate amplitude of small… more
Date: July 28, 1953
Creator: Trimpi, Robert L.
Partner: UNT Libraries Government Documents Department
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Review of experimental investigations of liquid-metal heat transfer

Description: Experimental data of various investigators of liquid-metal heat-transfer characteristics were reevaluated using as consistent assumptions and methods as possible and then compared with each other and with theoretical results. The reevaluated data for both local fully developed and average Nusselt numbers in the turbulent flow region were found still to have considerable spread, with the bulk of the data being lower than predicted by existing analysis. An equation based on empirical grounds whic… more
Date: November 4, 1954
Creator: Lubarsky, Bernard & Kaufman, Samuel J.
Partner: UNT Libraries Government Documents Department
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Formulas for the Elastic Constants of Plates With Integral Waffle-Like Stiffening

Description: "Formulas are derived for the fifteen elastic constants associated with bending, stretching, twisting, and shearing of plates with closely spaced integral ribbing in a variety of configurations and proportions. In the derivation the plates are considered, conceptually, as more uniform orthotropic plates somewhat on the order of plywood. The constants, which include the effectiveness of the ribs for resisting deformations other than bending and stretching in their longitudinal directions, are de… more
Date: 1954
Creator: Dow, Norris F.; Libove, Charles & Hubka, Ralph E.
Partner: UNT Libraries Government Documents Department
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A Study of the Problem of Designing Airplanes With Satisfactory Inherent Damping of the Dutch Roll Oscillation

Description: "Considerable interest has recently been shown in means of obtaining satisfactory stability of the dutch roll oscillation for modern high-performance airplanes without resort to complicated artificial stabilizing devices. One approach to this problem is to lay out the airplane in the earliest stages of design so that it will have the greatest practicable inherent stability of the lateral oscillation. The present report presents some preliminary results of a theoretical analysis to determine the… more
Date: 1954
Creator: Campbell, John P. & McKinney, Marion O., Jr.
Partner: UNT Libraries Government Documents Department
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Application of several methods for determining transfer functions and frequency response of aircraft from flight data

Description: In the process of analyzing the longitudinal frequency-response characteristics of aircraft, information on some of the methods of analysis has been obtained by the Langley Aeronautical Laboratory of the National Advisory Committee for Aeronautics. In the investigation of these methods, the practical applications and limitations were stressed. In general, the methods considered may be classed as: (1) analysis of sinusoidal response, (2) analysis of transient response as to harmonic content thro… more
Date: 1954
Creator: Eggleston, John M. & Mathews, Charles W.
Partner: UNT Libraries Government Documents Department
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A revised gust-load formula and a re-evaluation of v-g data taken on civil transport airplanes from 1933 to 1950

Description: From Summary: "A revised gust-load formula with a new gust factor is derived to replace the gust-load formula and alleviation factor widely used in gust studies. The revised formula utilizes the same principles and retains the same simple form of the original formula but provides a more appropriate and acceptable basis for gust-load calculations. The gust factor is calculated on the basis of a one-minus-cosine gust shape and is presented as a function of a mass-ratio parameter in contrast to th… more
Date: 1954
Creator: Pratt, Kermit G. & Walker, Walter G.
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.
Partner: UNT Libraries Government Documents Department
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Standard Atmosphere - Tables and Data for Altitudes to 65,800 Feet

Description: Report includes calculated detailed tables of pressures and densities of a standard atmosphere in both metric and english units for altitudes from -5,000 meters to 20,000 meters and from -16,500 feet to 65,800 feet. Tables, figures, physical constants, and basic equations are based upon the text, reproduced herein, of the manual of the ICAO standard atmosphere, International Civil Aviation Organization (ICAO) draft of December 1952.
Date: 1955
Partner: UNT Libraries Government Documents Department
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Buckling of thin-walled cylinder under axial compression and internal pressure

Description: An investigation was made of a thin-walled cylinder under axial compression and various internal pressures to study the effect of the internal pressure on the compressive buckling stress of the cylinder. A theoretical analysis based on a large-deflection theory was also made. The theoretically predicted increase of compressive buckling stress due to internal pressure agrees fairly well with the experimental results. (author).
Date: 1951
Creator: Lo, Hsu; Crate, Harold & Schwartz, Edward B.
Partner: UNT Libraries Government Documents Department
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Compressive strength of flanges

Description: The maximum compressive stress carried by a hinged flange is computed from a deformation theory of plasticity combined with the theory for finite deflections for this structure. The computed stresses agree well with those found experimentally. Empirical observation indicates that the results will also apply fairly well to the more commonly used flanges which are not hinged.
Date: 1951
Creator: Stowell, Elbridge Z.
Partner: UNT Libraries Government Documents Department
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A comparison of theory and experiment for high-speed free-molecule flow

Description: A comparison is made of free-molecule-flow theory with the results of wind-tunnel tests performed to determine the drag and temperature-rise characteristics of a transverse circular cylinder. The measured values of the cylinder center-point temperature confirmed the salient point of the heat-transfer analysis which was the prediction that an insulated cylinder would attain a temperature higher than the stagnation temperature of the stream. Good agreement was obtained between the theoretical and… more
Date: September 12, 1950
Creator: Stalder, Jackson R.; Goodwin, Glen & Creager, Marcus O.
Partner: UNT Libraries Government Documents Department
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A numerical method for the stress analysis of stiffened-shell structures under nonuniform temperature distributions

Description: A numerical method is presented for the stress analysis of stiffened-shell structures of arbitrary cross section under nonuniform temperature distributions. The method is based on a previously published procedure that is extended to include temperature effects and multicell construction. The application of the method to practical problems is discussed and an illustrative analysis is presented of a two-cell box beam under the combined action of vertical loads and a nonuniform temperature distrib… more
Date: September 12, 1950
Creator: Heldenfels, Richard R.
Partner: UNT Libraries Government Documents Department
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A General Integral Form of the Boundary-Layer Equation for Incompressible Flow With an Application to the Calculation of the Separation Point of Turbulent Boundary Layers

Description: "A general integral form of the boundary-layer equation, valid for either laminar or turbulent incompressible boundary-layer flow, is derived. By using the experimental finding that all velocity profiles of the turbulent boundary layer form essentially a single-parameter family, the general equation is changed to an equation for the space rate of change of the velocity-profile shape parameter. The lack of precise knowledge concerning the surface shear and the distribution of the shearing stress… more
Date: May 22, 1950
Creator: Tetervin, Neal & Lin, Chia Chiao
Partner: UNT Libraries Government Documents Department
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A study of effects of viscosity on flow over slender inclined bodies of revolution

Description: From Summary: "The observed flow field about slender inclined bodies of revolution is compared with the calculated characteristics based upon potential theory. The comparison is instructive in indicating the manner in which the effects of viscosity are manifest. Based on this and other studies, a method is developed to allow for viscous effects on the force and moment characteristics of bodies. The calculated force and moment characteristics of two bodies of high fineness ratio are shown to be … more
Date: 1951
Creator: Allen, H. Julian & Perkins, Edward W.
Partner: UNT Libraries Government Documents Department
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