Contribution to the Theory of Tail-Wheel Shimmy (open access)

Contribution to the Theory of Tail-Wheel Shimmy

A basic theoretical and experimental investigation is made of the shimmy behavior of a swiveling landing gear, the experimental tests being conducted with a small wheel mounted over a continuous belt. Effects of wheel loading, rolling velocity, rearward position of the wheel with respect to the swivel axis, tire elasticity, and torsional flexibility of the fuselage are investigated both experimentally and theoretically. A major theoretical conclusion is that the motion of a landing gear moving in a straight line without fuselage elasticity is stable for a sufficiently large rearward position of the wheel behind the swivel axis, and this conclusion is well verified quantitatively by the experimental data.
Date: December 1954
Creator: Melzer, M.
System: The UNT Digital Library
On the Spectrum of Natural Oscillations of Two-Dimensional Laminar Flows (open access)

On the Spectrum of Natural Oscillations of Two-Dimensional Laminar Flows

In the investigation of stability of a two-dimensional laminar flow with respect to small disturbances, a disturbance of the stream function moving downstream (in the direction of the x-axis) by the "partial wave formula" is described.
Date: December 1957
Creator: Grohne, D.
System: The UNT Digital Library
The Development of a Hollow Blade for Exhaust Gas Turbines (open access)

The Development of a Hollow Blade for Exhaust Gas Turbines

The subject of the development of German hollow turbine blades for use with internal cooling is discussed in detail. The development of a suitable blade profile from cascade theory is described. Also a discussion of the temperature distribution and stresses in a turbine blade is presented. Various methods of manufacturing hollow blades and the methods by which they are mounted in the turbine rotor are presented in detail.
Date: December 1950
Creator: Kohlmann, H.
System: The UNT Digital Library
The Diffusion of a Hot Air Jet in Air in Motion Part 2: The Flow Field in the Transition Zone (open access)

The Diffusion of a Hot Air Jet in Air in Motion Part 2: The Flow Field in the Transition Zone

The turbulent diffusion of a hot air jet in air can be divided into two zones, the core and the transition zone. The present report deals with the transitional zone.
Date: December 1950
Creator: Szablewski, W.
System: The UNT Digital Library
On the Calculation of Shallow Shells (open access)

On the Calculation of Shallow Shells

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.
System: The UNT Digital Library
On the Contribution of Turbulent Boundary Layers to the Noise Inside a Fuselage (open access)

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

"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 of linear systems to random forcing functions of several variables" (p. 1).
Date: December 1956
Creator: Corcos, G. M. & Liepmann, H. W.
System: The UNT Digital Library
On the Theory of Thin Shallow Shells (open access)

On the Theory of Thin Shallow Shells

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.
System: The UNT Digital Library
On the Theory of Anisotropic Shallow Shells (open access)

On the Theory of Anisotropic Shallow Shells

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.
System: The UNT Digital Library
Concerning the Flow About Ring-Shaped Cowlings Part 6: Further Measurements on Inlet Devices (open access)

Concerning the Flow About Ring-Shaped Cowlings Part 6: Further Measurements on Inlet Devices

"The present report presents as a supplement to the fourth report (available as ATI 5045, Air Materiel Command) in the series of investigations concerning the flow about ring-shaped cowlings further wind-tunnel measurements on inlet devices which are to show the influence of the radius of the nose of the cowling on the flow conditions. Moreover, a simple rule for the design of such arrangements, containing a hub in the interior, is suggested" (p. 1).
Date: December 1951
Creator: Küchemann, Dietrich & Weber, Johanna
System: The UNT Digital Library