Technical Report Archive & Image Library (TRAIL) - 1,438 Matching Results

Search Results

open access

The Principles of Turbulent Heat Transfer

Description: "The literature on turbulent heat transfer has in the course of years attained a considerable volume. Since this very complicated problem has not as yet found a complete solution, further studies in this field may be expected. The heat engineer must therefore accommodate himself to a constantly increasing number of theories and formulas. Since the theories generally start from hypothetical assumptions, and since they contain true and false assertions, verified knowledge and pure suppositions of… more
Date: September 1957
Creator: Reichardt, H.
Partner: UNT Libraries Government Documents Department
open access

Aerodynamic Forces on a Vibrating Unstaggered Cascade

Description: "The unsteady aerodynamic forces, [based on two-dimensional incompressible flow considerations], are determined for an unstaggered cascade, the blades of which are vibrating in phase in an approach flow parallel to the blades" (p. 1).
Date: August 1957
Creator: Söhngen, H.
Partner: UNT Libraries Government Documents Department
open access

Study of the Micro-Nonuniformity of the Plastic Deformation of Steel

Description: "The plastic flow during deformation of real polycrystalline metals has specific characteristics which distinguish the plastic deformation of metals from the deformation of ordinary isotropic bodies. One of these characteristics is the marked micro-nonuniformity of the plastic deformation of metals. P.O. Pashkov demonstrated the presence of a considerable micro-nonuniformity of the plastic deformation of coarse-grained steel wit medium or low carbon content" (p. 1).
Date: August 1957
Creator: Chechulin, B. B.
Partner: UNT Libraries Government Documents Department
open access

Reflection and Refraction of Acoustic Waves by a Shock Wave

Description: "The presence of sound waves in one or the other of the fluid regions on either side of a shock wave is made apparent, in the region under superpressure, by acoustic waves (reflected or refracted according to whether the incident waves lie in the region of superpressure or of subpressure) and by thermal waves. The characteristics of these waves are calculated for a plane, progressive, and uniform incident wave. In the case of refraction, the refracted acoustic wave can, according to the inciden… more
Date: July 1957
Creator: Brillouin, J.
Partner: UNT Libraries Government Documents Department
open access

Investigation of an Afterburning Ramjet Using Gaseous Hydrogen as Fuel at Mach Number of 3.0

Description: Memorandum presenting an investigation conducted in the supersonic wind tunnel on a 16-inch ramjet that was equipped with an afterburner and used gaseous hydrogen for both the primary and afterburner fuels. The primary nozzle had a contraction ratio of 0.6 while the exit nozzle had a contraction ratio of 0.9. Data were obtained at a free-stream Mach number of 3.0 and zero angle of attack.
Date: June 17, 1957
Creator: Wasserbauer, Joseph F.
Partner: UNT Libraries Government Documents Department
open access

Effect of Fatigue Crack on Static Strength: 2014-T6, 2024-T4, 6061-T6, 7075-T6 Open-Hole Monobloc Specimens

Description: "Static tensile test results are presented for specimens of 2014-T6, 2024-T4, 6061-T6, and 7075-T6 aluminum alloy containing fatigue cracks. The results are found to be in good agreement with the results reported for similar tests from other sources. The results indicate that the presence of a fatigue crack reduced the static strength, in all cases, by an amount larger than the corresponding reduction in net area; the 6061-T6 alloy specimens were least susceptible to the crack and the 7075-T6 a… more
Date: May 1957
Creator: Nordmark, Glenn E. & Eaton, Ian D.
Partner: UNT Libraries Government Documents Department
open access

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
Partner: UNT Libraries Government Documents Department
open access

The Effect of Solid Admixtures on the Velocity of Motion of a Free Dusty Air Jet

Description: "In dusty air flows occurring in industrial practice in transport by air pressure of friable materials, in the drying, annealing, and so forth, of a pulverized solid mass in suspension, and in other processes, the concentration of solid particles usually has a magnitude of the order of 1 kg per 1 kg of air. At such a concentration, the ratio of the volume of the particles to the volume of the air is small (less than one-thousandth part). However, regardless of this, the presence of a solid admi… more
Date: April 1957
Creator: Chernov, A. P.
Partner: UNT Libraries Government Documents Department
open access

Steady Nuclear Combustion in Rockets

Description: "The astrophysical theory of stationary nuclear reactions in stars is applied to the conditions that would be met in the practical engineering cases that would differ from the former, particularly with respect to the much lower combustion pressures, dimensions of the reacting volume, and burnup times. This application yields maximum rates of hear production per unit volume of reacting gas occurring at about 10(exp 8) K in the cases of reactions between the hydrogen isotopes, but yields higher r… more
Date: April 1957
Creator: Sänger, E.
Partner: UNT Libraries Government Documents Department
open access

NACA Conference on Aircraft Loads, Structures, and Flutter

Description: "This document contains reproductions of technical papers on some of the most recent research results on aircraft loads, flutter, and structures from the NACA laboratories. These papers were presented by members of the staff of the NACA laboratories at the Conference held at the Langley Aeronautical Laboratory March 5, 6, and 7, 1957. The primary purpose of this Conference was to convey to contractors of the military services and others concerned with the design of aircraft these recent researc… more
Date: March 5, 1957
Partner: UNT Libraries Government Documents Department
open access

On the Use of the Harmonic Linearization Method in the Automatic Control Theory

Description: "The method of harmonic linearization (harmonic balance), first proposed by N. M. Krylov and N. N. Bogolyubov for the approximate investigation of nonlinear vibrations, has been developed and received wide practical application to problems in the theory of automatic control. Recently, some doubt has been expressed on the legitimacy of application of the method to these problems, and assertions were made on the absence in them of a small parameter of any kind. Nevertheless, the method gives prac… more
Date: January 1957
Creator: Popov, E. P.
Partner: UNT Libraries Government Documents Department
open access

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.
Partner: UNT Libraries Government Documents Department
open access

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.
Partner: UNT Libraries Government Documents Department
open access

On the Calculation of Shallow Shells

Description: This paper considers a sufficiently thin shallow shell of nonzero Gaussian curvature. It also presents a system of symmetrically constructed differential equations, constructed by the mixed method through the stress function and the displpacement function.
Date: December 1956
Creator: Ambartsumyan, S. A.
Partner: UNT Libraries Government Documents Department
open access

On the Contribution of Turbulent Boundary Layers to the Noise Inside a Fuselage

Description: "The following report deals in preliminary fashion with the transmission through a fuselage of random noise generated on the fuselage skin by a turbulent boundary layer. The concept of attenuation is abandoned and instead the problem is formulated as a sequence of two linear couplings: the turbulent boundary layer fluctuations excite the fuselage skin in lateral vibrations and the skin vibrations induce sound inside the fuselage. The techniques used are those required to determine the response … more
Date: December 1956
Creator: Corcos, G. M. & Liepmann, H. W.
Partner: UNT Libraries Government Documents Department
open access

On the Theory of Anisotropic Shallow Shells

Description: A numerical analysis of thin-walled shallow shells is presented. Equations of equilibrium and relations between deformations and stresses are included along with fundamental differential equations.
Date: December 1956
Creator: Ambartsumyan, S. A.
Partner: UNT Libraries Government Documents Department
open access

On the Theory of Thin Shallow Shells

Description: This report is concerned with the theory of thin shallow shells. It does not employ the lines of curvature as the coordinate system, but employs "almost cartesian coordinates" or the coordinates obtained by cutting the surface into two mutually orthogonal systems of parallel planes.
Date: December 1956
Creator: Nazarov, A. A.
Partner: UNT Libraries Government Documents Department
open access

Aeroelastic Problems of Airplane Design

Description: The technical memorandum briefly summarizes the growth of interest in aeroelastic phenomena as aircraft speed increased and wing designs changed for faster aircraft. Different types of aircraft vibrations are then introduced, and the mathematical basis for the theory behind them is described. Special attention is given to static oscillations, wing flutter, and the flutter of skin panels. The last section of the memorandum deals with the prevention of flutter by design specifications.
Date: November 1956
Creator: Küssner, H. G.
Partner: UNT Libraries Government Documents Department
open access

Finite Span Wings in Compressible Flow

Description: Equations are developed using the source distribution method for the velocity potential function and pressure on thin wings in steady and unsteady motion. Closed form solutions are given for harmonically oscillating wings of general plan form including the effect of the wing wake. Some useful examples are presented in an appendix for arrow, semielliptical, and hexagonal plan form wings.
Date: September 1956
Creator: Krasilschchikova, E. A.
Partner: UNT Libraries Government Documents Department
open access

Effects of Intermittent Versus Continuous Heating upon the Tensile Properties of 2024-T4, 6061-T6 and 7075-T6 Alloys

Description: In some applications, aluminum alloys are subjected to intermittent heating at elevated temperature. It is generally considered that the effects of such intermittent heating are cumulative, and therefore are the same as if the heating had been continuous for the same total length of time. The object of these tests was to determine the effects of intermittent and continuous heating at 300 and 400 F, for total periods of 100 and 200 hr, upon the tensile properties of 2024-T4 and 6061-T6 alloy rol… more
Date: August 1956
Creator: Stickley, G. W. & Anerson, H. L.
Partner: UNT Libraries Government Documents Department
open access

The Fatigue Strength of Riveted Joints and Lugs

Description: This report deals with a number of tests on riveted joints and lugs for the primary purpose of comparing the several types of riveted joints and to study the effect of various factors on the fatigue strength of lugs. A check was made to ascertain whether or not an estimate of the fatigue life at a certain loading could be made from the dimensions of the joint and the fatigue data of the unnotched materials. Recommendations are made on the proportioning of joints to obtain better fatigue behavio… more
Date: August 1956
Creator: Schijve, J.
Partner: UNT Libraries Government Documents Department
open access

Safeguards Against Flutter of Airplanes

Description: This report is a compilation of practical rules, derived at the same time from theory and from experience, intended to guide the aeronautical engineer in the design of flutter-free airplanes. Rules applicable to the wing, the ailerons, flaps, tabs,tail surfaces, and fuselage are discussed.
Date: August 1956
Creator: De Vries, Gerhard
Partner: UNT Libraries Government Documents Department
open access

Tests to Determine the Adhesive Power of Passenger-Car Tires

Description: "The concept of the adhesive power of a tire with respect to the road involves several properties which result from the purpose of the tire; namely, connecting link between vehicle and road: (1) The tire must transfer the tractive and braking forces acting in the direction of travel (tractive and braking adhesion); (2) The tire is to prevent lateral deviations of the vehicle from the desired direction of travel (track adhesion)" (p. 1).
Date: August 1956
Creator: Förster, B.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen