UNT Libraries Government Documents Department - 28 Matching Results

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Buckling Tests on Eccentrically Loaded Beam Columns

Description: "Formulas are obtained for computing the buckling load of rods eccentrically loaded at each end, the computation being extended in particular to the inelastic range. The test results are graphically presented on three sets of curves. Two of these, at least for the elastic range, are independent of the material tested. The third set, which is independent of the material, possesses greater clearness and is therefore used for comparing the test results with the theoretical" (p. 1).
Date: October 1941
Creator: Cassens, J.
Item Type: Refine your search to only Report
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Calibration Tunnel for High Speed

Description: "For the investigation of measuring instruments at higher speeds up to a Mach number 0.7 a tunnel with closed test section was built in 1942 which was as simple and cheap as possible. The blower was a radial blower with straight sheet vanes of 800-millimeter diameter the tips of which were bent backward a little. The blower sucks the air through a honeycomb of diameter 1.2 meter with wide meshes" (p. 1).
Date: October 1946
Creator: Pretsch, J.
Item Type: Refine your search to only Report
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The Cause of Welding Cracks in Aircraft Steels

Description: The discussion in this article refers to gas welding of thin-walled parts of up to about 3 mm thickness. It was proven that by restricting the sulphur, carbon, and phosphorous content, and by electric-furnace production of the steel, it was possible in a short time to remove this defect. Weld hardness - i.e., martensite formation and hardness of the overheated zone - has no connection with the tendency to weld-crack development. Si, Cr, Mo, or V content has no appreciable effect, while increase… more
Date: October 1940
Creator: Müller, J.
Item Type: Refine your search to only Report
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A Class of de Laval Nozzles

Description: "A study is made herein of the irrotational adiabatic motion of a gas in the transition from subsonic to supersonic velocities. A shape of the de Laval nozzle is given, which transforms a homogeneous plane-parallel flow at large subsonic velocity into a supersonic flow without any shockwaves beyond the transition line from the subsonic to the supersonic regions of flow. The method of solution is based on integration near the transition line of the gas equations of motion in the form investigate… more
Date: October 1949
Creator: Falkovich, S. V.
Item Type: Refine your search to only Report
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The Compressible Potential Flow Past Elliptic Symmetrical Cylinders at Zero Angle of Attack and with No Circulation

Description: "For the tunnel corrections of compressible flows those profiles are of interest for which at least the second approximation of the Janzen-Rayleigh method can be applied in closed form. One such case is presented by certain elliptical symmetrical cylinders located in the center of a tunnel with fixed walls and whose maximum velocity, incompressible, is twice the velocity of flow. In the numerical solution the maximum velocity at the profile and the tunnel wall as well as the entry of sonic velo… more
Date: October 1942
Creator: Hantzsche, W. & Wendt, H.
Item Type: Refine your search to only Report
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Contribution to the Aerodynamics of Rotating-Wing Aircraft: Part 2

Description: "The interrelations established in an earlier report (NACA-TM-921) are used to study the best assumptions for hovering and horizontal flight. The effect of the twisted and tapered blade on the rotor efficiency is analyzed and the gliding coefficient at different stages (from autogyro to helicopter) of horizontal flight compared. To the extent that model or full-scale test data are available, they are included in the comparison" (p. 1).
Date: October 1941
Creator: Sissingh, G.
Item Type: Refine your search to only Report
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Contribution to the Design of Plywood Shells

Description: "The writer sets out to prove by calculation and experiment that by extensive utilization of the skin to carry axial load (reduction of stringer spacing) the stringer sections can be made small enough to afford a substantial saving in structural weight. This saving ranges from 5 to about 40 percent" (p. 1).
Date: October 1942
Creator: Blumrich, S.
Item Type: Refine your search to only Report
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Corrections on the Thermometer Reading in an Air Stream

Description: A method is described for checking a correction formula, based partly on theoretical considerations, for adiabatic compression and friction in flight tests and determining the value of the constant. It is necessary to apply a threefold correction to each thermometer reading. They are a correction for adiabatic compression, friction and for time lag.
Date: October 1940
Creator: Van der Maas, H. J. & Wynia, S.
Item Type: Refine your search to only Report
open access

Force- and Pressure-Distribution Measurements on Eight Fuselages

Description: "The present report deals with force- and pressure-distribution measurements on a number of fuselage forms of varying slenderness ratio, varying rearward position of maximum thickness, and varying nose ratio. The effect of these parameters on the force and moment coefficients was determined. The linearity of the difference between the theoretical and experimental fuselage moments with the friction lift made it possible to indicate a neutral point and its travel with the different parameters" (p… more
Date: October 1948
Creator: Lange, G.
Item Type: Refine your search to only Report
open access

Heat Transfer in a Turbulent Liquid or Gas Stream

Description: "The theory of heat.transfer from a solid body to a liquid stream could he presented previously only with limiting assumptions about the movement of the fluid (potential flow, laminar frictional flow). (See references 1, 2, and 3). For turbulent flow, the most important practical case, the previous theoretical considerations did not go beyond dimensionless formulas and certain conclusions as to the analogy between the friction factor and the unit thermal conductance, (See references 4, 5, 6, an… more
Date: October 1944
Creator: Latzko, H.
Item Type: Refine your search to only Report
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Heat Transfer in the Turbulent Boundary Layer of a Compressible Gas at High Speeds

Description: "The Reynolds law of heat transfer from a wall to a turbulent stream is extended to the case of flow of a compressible gas at high speeds. The analysis is based on the modern theory of the turbulent boundary layer with laminar sublayer. The investigation is carried out for the case of a plate situated in a parallel stream. The results are obtained independently of the velocity distribution in the turbulent boundar layer" (p. 1).
Date: October 1942
Creator: Frankl, F. & Voishel, V.
Item Type: Refine your search to only Report
open access

Heat Transfer Over the Circumference of a Heated Cylinder in Transverse Flow

Description: "A method for recording the local heat-transfer coefficients on bodies in flow was developed. The cylinder surface was kept at constant temperature by the condensation of vapor except for a narrow strip which is heated separately to the same temperature by electricity. The heat-transfer coefficient at each point was determined from the electric heat output and the temperature increase" (p. 1).
Date: October 1943
Creator: Schmidt, Ernst & Wenner, Karl
Item Type: Refine your search to only Report
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Investigation of the Operating Properties of the Leakage Current Anemometer

Description: "Freedom from inertia, erosion of electrodes, and reaction make the leakage current particularly appropriate for the measurement of flow velocities in gases. Apparatus previously described has now been improved by reducing the size of the electrodes by one -thousandth, as is necessary aerodynamically, and by increasing the magnitude of the current from 1000 to 10,000 times; the latter result was obtained.by use of mercury high-pressure lamps set up at the one focal point of an ellipsoidal refle… more
Date: October 1947
Creator: Fucks, Wilhelm
Item Type: Refine your search to only Report
open access

Investigation of Turbulent Mixing Processes

Description: "With water as driving medium and delivered medium in a device similar to a simple jet apparatus, the pressure and velocity fields of the mixing zone were explored with a pitot bar; the ratio of delivered to driving volume ranged between the values 0, 1, 2, and 4. An attempt was also made to analyze the mixing flow mathematically by integration of the equation of motion, with the aid of conventional formulas for the turbulent shearing stress, but this succeeded only approximately for the very s… more
Date: October 1946
Creator: Viktorin, K.
Item Type: Refine your search to only Report
open access

Lift Force of an Arrow-Shaped Wing

Description: "The flow about a conical body of an ideal compressible fluid is considered. Assume that the velocity of the oncoming flow at infinity W is directed along the z-axis. The system of Cartesian coordinates x, y, z with origin at the vertex of the cone O is shown" (p. 1).
Date: October 1949
Creator: Gurevich, M. I.
Item Type: Refine your search to only Report
open access

On the Application of the Energy Method to Stability Problems

Description: "Since stability problems have come into the field of vision of engineers, energy methods have proved to be one of the most powerful aids in mastering them. For finding the especially interesting critical loads special procedures have evolved that depart somewhat from those customary in the usual elasticity theory. A clarification of the connections seemed desirable,especially with regard to the post-critical region, for the treatment of which these special methods are not suited as they are" (… more
Date: October 1947
Creator: Marguerre, Karl
Item Type: Refine your search to only Report
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On the Sound Field of a Rotating Propeller

Description: "The sound field of a rotating propeller is treated theoretically on the basis of aerodynamic principles. For the lower harmonics, the directional characteristics and the radiated sound energy are determined and are in conformity with existing experimental results" (p. 1).
Date: October 1948
Creator: Gutin, L.
Item Type: Refine your search to only Report
open access

The Oscillating Wing With Aerodynamically Balanced Elevator

Description: "The two-dimensional problem of the oscillating wing with aerodynamically balanced elevator is treated in the manner that the wing is replaced by a plate with bends and stages and the airfoil section by a mean line consisting of one or more straights. The computed formulas and tables permit, on these premises, the prediction of the pressure distribution and of the aerodynamic reactions of oscillating elevators and tabs with any position of elevator hinge in respect to elevator leading edge" (p.… more
Date: October 1941
Creator: Küssner, H. G. & Schwartz, I.
Item Type: Refine your search to only Report
open access

Plane and Three-Dimensional Flow at High Subsonic Speeds

Description: "For two- and three-dimensional flow in a compressible medium, a simple relation is given by which, to a first approximation, the quantitative influence of compressibility upon the velocities and pressures can be understood in a clear manner. In the application of this relation the distinct behaviors of two-dimensional and axially symmetric three-dimensional flow with increasing Mach number are brought out. For slender elliptic cylinders and ellipsoids of revolution, calculations are made of th… more
Date: October 1946
Creator: Göthert, B.
Item Type: Refine your search to only Report
open access

A Ram-Jet Engine for Fighters

Description: Simple and accurate calculations are made of the flow process in a continuous compressorless Lorin jet-propulsion unit. Experimental confirmation is given from towing tests on an airplane at flying speeds up to 200 miles per second. An analysis is made of the performance of a fighter-type airplane designed for utilization of this propulsion system.
Date: October 1947
Creator: Sänger, E. & Bredt, I.
Item Type: Refine your search to only Report
open access

Resonance Vibrations in Intake and Exhaust Pipes of in-Line Engines 3: The Inlet Process of a Four-Stroke-Cycle Engine

Description: Using a previously developed method, the boundary process of four-stroke-cycle engines are set up. The results deviate considerably from those obtained under the assumption that the velocity fluctuation is proportional to the cylinder piston motion. The deviation is less at the position of resonance frequencies. By the method developed, the effect of the resonance vibrations on the volumetric efficiency can be demonstrated.
Date: October 1940
Creator: Lutz, O.
Item Type: Refine your search to only Report
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