Technical Report Archive & Image Library (TRAIL) - 1,423 Matching Results

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Thin airfoil theory based on approximate solution of the transonic flow equation

Description: A method is presented for the approximate solution of the nonlinear equations of transonic flow theory. Solutions are found for two-dimensional flows at a Mach number of 1 and for purely subsonic and purely supersonic flows. Results are obtained in closed analytic form for a large and significant class of nonlifting airfoils. At a Mach number of 1 general expressions are given for the pressure distribution on an airfoil of specified geometry and for the shape of an airfoil having a prescribed p… more
Date: 1958
Creator: Spreiter, John R. & Alksne, Alberta Y.
Partner: UNT Libraries Government Documents Department
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Thin Oblique Airfoils at Supersonic Speed

Description: "The well-known methods of thin-airfoil theory have been extended to oblique or sweptback airfoils of finite aspect ratio moving at supersonic speeds. The cases considered thus far are symmetrical airfoils at zero lift having plan forms bounded by straight lines. Because of the conical form of the elementary flow fields, the results are comparable in simplicity to the results of the two-dimensional thin-airfoil theory for subsonic speeds" (p. 267).
Date: May 23, 1946
Creator: Jones, Robert T.
Partner: UNT Libraries Government Documents Department
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Thirty-Seventh Annual Report of the National Advisory Committee for Aeronautics: Administrative Report Including Technical Report Nos. 1003 to 1058

Description: "In accordance with the act of Congress, approved March 3,1915 (U.S. C. title 50, sec. 151), which established the National Advisory Committee for Aeronautics the Committee submits its thirty-seventh annual report for the fiscal year 1951. The United States is engaged in expanding military aviation to levels never before reached except in the midst of a major war. In Korea, our military aircraft are engaged in combat with airplanes of an unfriendly nation evidently able to build military aircra… more
Date: 1952
Partner: UNT Libraries Government Documents Department
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Three-dimensional transonic flow theory applied to slender wings and bodies

Description: The present paper re-examines the derivation of the integral equations for transonic flow around slender wings and bodies of revolution, giving special attention to conditions resulting from the presence of shock waves and to the reduction of the relations to the special forms necessary for the discussion of sonic flow, that is, flow at free-stream Mach number 1.
Date: April 2, 1956
Creator: Heaslet, Max A. & Spreiter, John R.
Partner: UNT Libraries Government Documents Department
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Three methods of calculating range and endurance of airplanes

Description: This report develops new equations which give the range and endurance of airplanes with an accuracy equal to that obtained from a step-by-step integration of the flight. A method of obtaining equally satisfactory results from Brequet's equations is also given in detail. A third method of calculating range and endurance, derived by the writer for use in routine estimating in the Bureau of Aeronautics, is also given in full. The reports contains tables and curves arranged for convenient use and i… more
Date: January 1927
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
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The Torsion of Members Having Sections Common in Aircraft Construction

Description: "Within recent years a great variety of approximate torsion formulas and drafting-room processes have been advocated. In some of these, especially where mathematical considerations are involved, the results are extremely complex and are not generally intelligible to engineers. The principal object of this investigation was to determine by experiment and theoretical investigation how accurate the more common of these formulas are and on what assumptions they are founded and, if none of the propo… more
Date: 1930
Creator: Trayer, George W. & March, H. W.
Partner: UNT Libraries Government Documents Department
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Torsion of wing trusses at diving speeds

Description: The purpose of this report is to indicate what effect the distortion of a typical loaded wing truss will have upon the load distribution. The case of high angle of incidence may be dismissed immediately from consideration as the loads on the front and rear trusses are balanced, and consequently there will be little angular distortion. A given angular distortion will have the maximum effect upon load distribution in the region of the angle of no-lift, because the slope of the lift curve is highe… more
Date: 1921
Creator: Miller, Roy G.
Partner: UNT Libraries Government Documents Department
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Torsion Tests of Tubes

Description: "This report presents the results of tests of 63 chromium-molybdenum steel tubes and 102 17st aluminum-alloy tubes of various sizes and lengths made to study the dependence of the torsional strength on both the dimensions of the tube and the physical properties of the tube material. Three types of failure are found to be important for sizes of tubes frequently used in aircraft construction: (1) failure by plastic shear, in which the tube material reached its yield strength before the critical t… more
Date: February 1937
Creator: Stang, Ambrose H.; Ramberg, Walter & Back, Goldie
Partner: UNT Libraries Government Documents Department
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The Torsional and Bending Deflection of Full-Scale Aluminum-Alloy Propeller Blades Under Normal Operating Conditions

Description: "The torsional deflection of the blades of three full-scale aluminum-alloy propellers operating under various loading conditions was measured by a light-beam method. Angular bending deflections were also obtained as an incidental part of the study. The deflection measurements showed that the usual present-day type of propeller blades twisted but a negligible amount under ordinary flight conditions. A maximum deflection of about 1/10 degree was found at a v/nd of 0.3 and a smaller deflection at … more
Date: 1938
Creator: Hartman, Edwin P. & Biermann, David
Partner: UNT Libraries Government Documents Department
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Torsional Stiffness of Thin-Walled Shells Having Reinforcing Cores and Rectangular, Triangular, or Diamond Cross Section

Description: "A theoretical investigation has been made of the Saint-Venant torsion of certain composite bars. These bars are composed of two materials -- one material in the form of a thin-walled cylindrical shell and the other material in the form of a core which fills the interior of the shell and is bonded to it. An approximate boundary-value problem is formulated on assumptions similar to those of the theory of torsion of hollow thin-walled shells (Bredt theory)" (p. 771).
Date: June 7, 1956
Creator: McComb, Harvey G., Jr.
Partner: UNT Libraries Government Documents Department
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The torsional strength of wings

Description: This report describes a simple method for calculating the position of the elastic axis of a wing structure having any number of spars. It is shown that strong drag bracing near the top and bottom of a wing greatly increases the torsional strength. An analytical procedure for finding the contribution of the drag bracing to the torsional strength and stiffness is described, based upon the principle of least work, and involving only one unknown quantity. A coefficient for comparing the torsional r… more
Date: December 1928
Creator: Burgess, C. P.
Partner: UNT Libraries Government Documents Department
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The Transition Phase in the Take-Off of an Airplane

Description: Report presents the results of an investigation to determine the character and importance of the transition phase between the ground run and steady climb in the take-off of an airplane and the effects of various factors on this phase and on the air-borne part of the take-off as a whole. The information was obtained from a series of step-by-step integrations, which defined the motion of the airplane during the transition and which were based on data derived from actual take-off tests of a Vervil… more
Date: October 26, 1937
Creator: Wetmore, J. W.
Partner: UNT Libraries Government Documents Department
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Transonic flow past a wedge profile with detached bow wave

Description: "A theoretical study has been made of the aerodynamic characteristics at zero angle of attack of a thin, doubly symmetrical double-wedge profile in the range of supersonic flight speed in which the bow wave is detached. The analysis utilizes the equations of the transonic small-disturbance theory and involves no assumptions beyond those implicit in this theory. The mixed flow about the front half of the profile is calculated by relaxation solution of boundary conditions along the shock polar an… more
Date: 1952
Creator: Vincenti, Walter G. & Wagoner, Cleo B.
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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Transverse Vibrations of Hollow Thin-Walled Cylindrical Beams

Description: "The variational principle, differential equations, and boundary conditions considered appropriate to the analysis of transverse vibrations of hollow thin-walled cylindrical beams are shown. General solutions for the modes and frequencies of cantilever and free-free cylindrical beams of arbitrary cross section but of uniform thickness are given. The combined influence of the secondary effects of transverse shear deformation, shear lag, and secondary effects of transverse shear deformation, shea… more
Date: 1953
Creator: Budiansky, Bernard & Kruszewski, Edwin T.
Partner: UNT Libraries Government Documents Department
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A Turbulence Indicator Utilizing the Diffusion of Heat

Description: This report describes a method of determining the turbulence in wind tunnels. The effect of turbulence upon the diffusion of heat from a small electrically heated wire in an air stream was investigated. The turbulence of the stream was introduced by a series of geometrically similar screens placed one at a time across the upstream section of the tunnel. With the wire set at various distances from the screens, curves of temperature distribution were obtained by traversing the heated wake at a di… more
Date: March 8, 1935
Creator: Schubauer, G. B.
Partner: UNT Libraries Government Documents Department
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The twenty-foot propeller research tunnel of the National Advisory Committee for Aeronautics

Description: This report describes in detail the new propeller research tunnel of the National Advisory Committee for Aeronautics at Langley Field, Va. This tunnel has an open jet air stream 20 feet in diameter in which velocities up to 110 M. P. H. Are obtained. Although the tunnel was built primarily to make possible accurate full-scale tests on aircraft propellers, it may also be used for making aerodynamic tests on full-size fuselages, landing gears, tail surfaces, and other aircraft parts, and on model… more
Date: January 1929
Creator: Weick, Fred E. & Wood, Donald H.
Partner: UNT Libraries Government Documents Department
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Two-and Three-Dimensional Unsteady Lift Problems in High-Speed Flight

Description: "The problem of transient lift on two- and three-dimensional wings flying at high speeds is discussed as a boundary-value problem for the classical wave equation. Kirchoff's formula is applied so that the analysis is reduced, just as in the steady state, to an investigation of sources and doublets. The applications include the evaluation of indicial lift and pitching-moment curves for two-dimensional sinking and pitching wings flying at Mach numbers equal to 0, 0.8, 1.0, 1.2 and 2.0" (p. 393).
Date: October 12, 1950
Creator: Lomax, Harvard; Heaslet, Max A.; Fuller, Franklyn B. & Sluder, Loma
Partner: UNT Libraries Government Documents Department
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Two-dimensional compressible flow in centrifugal compressors with straight blades

Description: "Six numerical examples are presented for steady, two-dimensional, compressible, nonviscous flow in centrifugal compressors with thin straight blades, the center lines of which generate the surface of a right circular cone when rotated about the axis of the compressor. A seventh example is presented for incompressible flow. The solutions were obtained in a region of the compressors, including the impeller tip, that was considered to be unaffected by the diffuser vanes or by the impeller-inlet c… more
Date: June 21, 1949
Creator: Stanitz, John D. & Ellis, Gaylord O.
Partner: UNT Libraries Government Documents Department
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Two-Dimensional Compressible Flow in Turbomachines With Conic Flow Surfaces

Description: "A general method of analysis is developed for two-dimensional, steady, compressible flow in stators or rotors of radial and mixed flow turbomachines with conic flow surfaces (surfaces of right circular cones generated by center line of flow passage in the axial-radial plane). The variables taken into account are: (1) tip speed of the rotor, (2) flow rate, (3) blade shape, (4) variation in passage height with radius, (5) number of blades, and (6) cone angle of the flow surface. Relaxation metho… more
Date: 1949
Creator: Stanitz, John D.
Partner: UNT Libraries Government Documents Department
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Two-Dimensional Subsonic Compressible Flow Past Elliptic Cylinders

Description: "The method of Poggi is used to calculate, for perfect fluids, the effect of compressibility upon the flow on the surface of an elliptic cylinder at zero angle of attack and with no circulation. The result is expressed in a closed form and represents a rigorous determination of the velocity of the fluid at the surface of the obstacle insofar as the second approximation is concerned. Comparison is made with Hooker's treatment of the same problem according to the method of Janzen and Rayleight an… more
Date: February 11, 1938
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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Two-dimensional unsteady lift problems in supersonic flight

Description: The variation of pressure distribution is calculated for a two-dimensional supersonic airfoil either experiencing a sudden angle-of-attack change or entering a sharp-edge gust. From these pressure distributions the indicial lift functions applicable to unsteady lift problems are determined for two cases. Results are presented which permit the determination of maximum increment in lift coefficient attained by an unrestrained airfoil during its flight through a gust. As an application of these re… more
Date: December 5, 1947
Creator: Heaslet, Max A. & Lomax, Harvard
Partner: UNT Libraries Government Documents Department
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