Technical Report Archive & Image Library (TRAIL) - 188 Matching Results

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A Theoretical Investigation of the Drag of Generalized Aircraft Configurations in Supersonic Flow

Description: "It seems possible that, in supersonic flight, unconventional arrangements of wings and bodies may offer advantages in the form of drag reduction. It is the purpose of this report to consider the methods for determining the pressure drag for such unconventional configurations, and to consider a few of the possibilities for drag reduction in highly idealized aircraft. The idealized aircraft are defined by distributions of lift and volume in three-dimensional space, and Hayes' method of drag eval… more
Date: January 1957
Creator: Graham, E. W.; Lagerstrom, P. A.; Licher, R. M. & Beane, B. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical Investigations on the Efficiency and the Conditions for the Realization of Jet Engines

Description: Contents: Preliminary notes on the efficiency of propulsion systems; Part I: Propulsion systems with direct axial reaction rockets and rockets with thrust augmentation; Part II: Helicoidal reaction propulsion systems; Appendix I: Steady flow of viscous gases; Appendix II: On the theory of viscous fluids in nozzles; and Appendix III: On the thrusts augmenters, and particularly of gas augmenters.
Date: June 1950
Creator: Roy, Maurice
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Theories of Turbulence

Description: "The theory of turbulence reached its full growth at the end of the 19th century as a result of the work by Boussinesq and Reynolds. It then underwent a long period of stagnation which ended under the impulse given to it by the development of wind tunnels caused by the needs of aviation. Numerous researchers, attempted to put Reynolds' elementary statistical theory into a more precise form. During the war, some isolated scientists - von Weizsacker and Heisenberg in Germany, Kolmogoroff in Russi… more
Date: October 1955
Creator: Agostini, L. & Bass, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory and Experiments on Supersonic Air-to-Air Ejectors

Description: A comparison of experiment with theory is made for air ejectors having cylindrical mixing sections and operating under conditions of supersonic primary flow and either mixed or supersonic regimes of mixing. The effect on ejector performance of such parameters as mixer length and cross section, terminating diffuser, primary Mach number, and primary nozzle position is presented in terms of mass flow and pressure ratio.
Date: September 1958
Creator: Fabri, J. & Paulon, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Dynamic Creep

Description: An analysis is given of the causes of the increase in the creep of a material under dynamic loads. A theory of dynamic creep is proposed based on the after-effect theory of Becker. Three circumstances that must be taken into account when theoretically treating dynamic creep are provided.
Date: September 1955
Creator: Predvoditelev, A. A. & Smirnov, B. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Flame Propagation

Description: "The mechanism of flame propagation has been qualitatively formulated. In accordance with this formulation, the chemical reaction initiated in some layer brings about an increase in the temperature; because of the heat conduction, the temperature is raised in the neighboring layer where in turn the chemical reaction is initiated. In this manner the flame is propagated" (p. 1).
Date: June 1951
Creator: Zeldovich, Y. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Plane, Symmetrical Intake Diffusers

Description: "The present report ties in with the investigations on the inlet diffusers by P. Ruden. The theory developed by Ruden had produced results which found excellent confirmation in wind-tunnel tests and in spite of certain still-existing defects, are technically very promising. The reasons for the new theory of the diffuser forms indicated by Ruden are twofold: first, the arguments adduced in Ruden's theory deal only with one specific operating condition, that is, a certain ratio of mean velocity w… more
Date: April 1950
Creator: Brödel, Walter
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Reversible and Nonreversible Cracks in Solids

Description: The Griffith crack theory is reviewed and certain shortcomings of this theory are discussed. A new description for the shape of a crack is given which takes into account the atomic structure of material. Through consideration of the total energy of the system and the shape of the crack, expressions for crack behavior are derived which are considered to remedy the defects of the Griffith theory.
Date: April 1955
Creator: Frenkel, Y. I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Thin-Walled Rods

Description: Starting with the Love equations for bending of extensible shells, "principal stress states" are sought for a thin-walled rod of arbitrary but open cross section. Principal stress states exclude those local states arising from end conditions which damp out with distance from the ends. It is found that for rods of intermediate length, long enough to avoid local bending at a support, and short enough that elementary torsion and bending are not the most significant stress states, four principal st… more
Date: October 1951
Creator: Goldenveizer, A. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Three Papers From Conference On "Wing and Tail-Surface Oscillations: March 6-8, 1941, Munich

Description: Memorandum presenting three papers regarding aerodynamic balance of control surfaces. The specific topics covered include some general remarks regarding aerodynamically balanced control surfaces, aerodynamically equivalent systems for various forms of control surfaces within the scope of two-dimensional wing theory, and comparative calculations concerning aerodynamic balance of control surfaces.
Date: August 1951
Creator: Söhngen, Heinz; Schwarz, L. & Dietze, F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transition Caused by the Laminar Flow Separation

Description: An experimental investigation of the effects of the geometry of body surface, Reynolds number, stream turbulence, and a roughness element (wire) on the reattachment of separated laminar boundary-layer flow on a bent flat plate is presented and discussed. The flow mechanisms determining reattachment of the boundary layer are analyzed and discussed.
Date: September 1952
Creator: Maekawa, T. & Atsumi, Shoichi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Translational Motion of Bodies Under the Free Surface of a Heavy Fluid of Finite Depth

Description: In the present paper, the two-dimensional problem of the wave motion produced in a heavy fluid of finite depth by the horizontal rectilinear and uniform motion of a solid body of arbitrary shape immersed under the surface of the fluid is considered by the method of N. E. Kochin.
Date: June 1952
Creator: Haskind, M. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Turbulence and Heat Stratification

Description: With applications to meteorology in view, the method of small oscillations is used to investigate the stability of a plane laminar boundary layer in which the density depends in a special way on the distance from the plate. It is found that for a constant Froude number the flow becomes more stable as the Richardson number increases until, at a critical value of the Richardson number that depends on the Froude number, the flow is stable for all disturbance wave lengths and Reynolds numbers. The … more
Date: October 1950
Creator: Schlichting, Hermann
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Turbulence in the Wake of a Thin Airfoil at Low Speeds

Description: From Summary: "Experiments have been made to determine the nature of turbulence in the wake of a two-dimensional airfoil at low speeds. The experiments were motivated by the need for data which can be used for analysis of the tail-buffeting problem in aircraft design. Turbulent intensity and power spectra of the velocity fluctuations were measured at a Reynolds number of 1.6 x 10(exp 5) for several angles of attack. Total-head measurements were also obtained in an attempt to relate steady and f… more
Date: January 1957
Creator: Campbell, George S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Turbulent Boundary Layer on a Rough Curvilinear Surface

Description: "A number of semiempirical approximate methods exist for determining the characteristics of the turbulent boundary layer on a curvilinear surface. At present, among these methods, the one proposed by L. G. Loitsianskii is given frequent practical application. This method is sufficiently effective and permits, in the case of wing profiles with technically smooth surfaces, calculating the basic characteristics of the boundary layer and the values of the overall drag with an accuracy which suffice… more
Date: September 1958
Creator: Droblenkov, V. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Two-Dimensional Symmetrical Inlets With External Compression

Description: The purpose of inlets like, for instance, those of air-cooled radiators and scoops is to take a certain air quantity out of the free stream and to partly convert the free-stream velocity into pressure. In the extreme case this pressure conversion may occur either entirely in the interior of the inlet (inlet with internal compression) or entirely in the free stream ahead of the inlet (inlet with external compression). In this report a theory for two-dimensional inlets with external compression i… more
Date: March 1950
Creator: Ruden, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Unstable Capillary Waves on Surface of Separation of Two Viscous Fluids

Description: "The study of the breakup of a liquid jet moving in another medium, for example, a jet of fuel from a nozzle, shows that for sufficiently large outflow velocities the jet breaks up into a certain number of drops of different diameters. At still larger outflow velocities, the continuous part of the jet practically vanishes and the jet immediately breaks up at the nozzle into a large number of droplets of varying diameters (the case of "atomization"). The breakup mechanism in this case has a very… more
Date: April 1951
Creator: Borodin, V. A. & Dityakin, Y. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vibration of a Wing of Finite Span in a Supersonic Flow

Description: An investigate ion was made of the disturbed motion of a gas for the harmonic vibrations of a thin slightly cambered wing of finite span moving forward with supersonic velocity. This problem was considered by E. A. Krasilshchikova who applied the method of Fourier series and obtained a solution of the space problem for the condition that the Mach cones drawn through the leading edge of the wing intersect the wing or are tangent to it. In this paper, a different method of solution is given, whic… more
Date: April 1950
Creator: Haskind, M. D. & Falkovich, S. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wall Interference in a Perforated Wind Tunnel

Description: "The theory of cascades, made up of a series of flat plates placed one behind the other, is extended to the case where the impinging stream is not uniform, and the deduced properties of this cascade-flow are then applied to the study of the wall interference between such as cascade-like boundary and a vortex-source type of singularity. It is shown that the induced velocities, produced by the presence of such a wall, are equal to what is obtained by action of a suitably chosen 'reflected' singul… more
Date: May 1957
Creator: Brescia, Riccardo
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Corrections at High Subsonic Speeds Particularly for an Enclosed Circular Tunnel

Description: A review of existing publications on wind-tunnel corrections is followed by an approximate method for determining the corrections due to model and wake displacement and to lift. Relations are investigated for fuselages and wings of various spans in closed circular tunnels. A comparison is made between the computations and the tests in the DVL high-speed wind tunnel.
Date: February 1952
Creator: Göthert, Bernhard Hermann
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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