UNT Libraries Government Documents Department - 37 Matching Results

Search Results

Results: 1 - 24 next
open access

Boundary Layer Removal by Suction

Description: Flight-test data and wind-tunnel data on suction profiles are substantially in agreement. The lift values found in the model test can be actually flown and used as a basis for the design. To visualize the action of the suction, the flow conditions with and without suction on the upper surface were photographed; figures 12 to 15 are sections of the film.
Date: April 1941
Creator: Schrenk, O.
Item Type: Refine your search to only Report
open access

Boundary Layer Theory, Part 2, Turbulent Flows

Description: From Summary: "The flow laws of the actual flows at high Reynolds numbers differ considerably from those of the laminar flows treated in the preceding part. These actual flows show a special characteristic, denoted as turbulence. The character of a turbulent flow is most easily understood the case of the pipe flow. Consider the flow through a straight pipe of circular cross section and with a smooth wall. For laminar flow each fluid particle moves with uniform velocity along a rectilinear path." more
Date: April 1949
Creator: Schlichting, H.
Item Type: Refine your search to only Report
open access

Calculation of Centrally Loaded Thin-Walled Columns Above the Buckling Limit

Description: "When thin-walled columns formed from flanged sheet, such as used in airplane construction, are subjected to axial load, their behavior at failure varies according to the slenderness ratio. On long columns the axis deflects laterally while the cross section form is maintained; buckling results. The respective breaking load in the elastic range is computed by Euler's formula and for the plastic range by the Engesser- Karman formula. Its magnitude is essentially dependent upon the length" (p. 1).
Date: April 1945
Creator: Reinitzhuber, F.
Item Type: Refine your search to only Report
open access

The Combination of Internal-Combustion Engine and Gas Turbine

Description: "While the gas turbine by itself has been applied in particular cases for power generation and is in a state of promising development in this field, it has already met with considerable success in two cases when used as an exhaust turbine in connection with a centrifugal compressor, namely, in the supercharging of combustion engines and in the Velox process, which is of particular application for furnaces. In the present paper the most important possibilities of combining a combustion engine wi… more
Date: April 1947
Creator: Zinner, K.
Item Type: Refine your search to only Report
open access

The Distribution of Loads on Rivets Connecting a Plate to a Beam Under Transverse Loads

Description: "This report gives theoretical discussion of the distribution of leads on rivets connecting a plate to a beam under transverse leads. Two methods of solution are given which are applicable to loads up to the limit of proportionality; in the first the rivets are treated as discrete members, and in the second they are replaced by a continuous system of jointing. A method of solution is also given which is applicable to the case when nonlinear deformations occur in the rivets and the plate, but no… more
Date: April 1947
Creator: Vogt, F.
Item Type: Refine your search to only Report
open access

The Effect of Turbulence on the Flame Velocity in Gas Mixtures

Description: "The present report deals with the effect of turbulence on the propagation of the flame. Being based upon experiments with laminar as well as turbulent Bunsen flames, both the physico-chemical and the hydro-dynamical aspects of the problem are analyzed. A number of new deductions, interesting from the point of view of engine combustion and other very rapidly changing flame reactions, are made" (p. 1).
Date: April 1947
Creator: Damköhler, Gerhard
Item Type: Refine your search to only Report
open access

The Efficiency of Combustion Turbines With Constant-Pressure Combustion

Description: "Of the two fundamental cycles employed in combustion turbines, namely, the explosion (or constant-volume) cycle and the constant-pressure cycle, the latter is considered more in detail and its efficiency is derived with the aid of the cycle diagrams for the several cases with adiabatic and isothermal compression and expansion strokes and with and without utilization of the exhaust heat. Account is also taken of the separate efficiencies of the turbine and compressor and of the pressure losses … more
Date: April 1941
Creator: Piening, Werner
Item Type: Refine your search to only Report
open access

Exact Calculation of Laminar Boundary Layer in Longitudinal Flow Over a Flat Plate With Homogeneous Suction

Description: "Lately it has been proposed to reduce the friction drag of a body in a flow for the technically important large Reynolds numbers by the following expedient: the boundary layer, normally turbulent, is artificially kept laminar up to high Reynolds numbers by suction. The reduction in friction drag thus obtained is of the order of magnitude of 60 to 80 percent of the turbulent friction drag, since the latter, for large Reynolds numbers, is several times the laminar friction drag. In considering t… more
Date: April 1949
Creator: Iglisch, Rudolf
Item Type: Refine your search to only Report
open access

Experimental Investigation of a Model of a Two-Stage Turboblower

Description: "In the present paper an investigation is made of two stages of a multistage turboblower having a vaneless diffuser behind the impeller and guide vanes at the inlet to the nest stage. The method employed was that of investigating the performance of the successive elements of the blower (the impeller, vaneless diffuser, ets.) whereby the kinematics of the flow through the blower could be followed and the pressure at the different points computed. The character of the flow and the physical signif… more
Date: April 1943
Creator: Dovjik, S. & Polikovsky, W.
Item Type: Refine your search to only Report
open access

Fundamentals of the Control of Gas-Turbine Power Plants for Aircraft, Part 1: Standardization of the Computations Relating to the Control of Gas-Turbine Power Plants for Aircraft by the Employment of the Laws of Similarity

Description: "It will be shown that by the use of the concept of similarity a simple representation of the characteristic curves of a compressor operating in combination with a turbine may be obtained with correct allowance for the effect of temperature. Furthermore, it becomes possible to simplify considerably the rather tedious investigations of the behavior of gas-turbine power plants under different operating conditions. Characteristic values will be derived for the most important elements of operating … more
Date: April 1947
Creator: Kühl, H.
Item Type: Refine your search to only Report
open access

Fundamentals of the Control of Gas-Turbine Power Plants for Aircraft, Part 2: Principles of Control Common to Jet, Turbine-Propeller Jet, and Ducted-Fan Jet Power Plants

Description: "After defining the aims and requirements to be set for a control system of gas-turbine power plants for aircraft, the report will deal with devices that prevent the quantity of fuel supplied per unit of time from exceeding the value permissible at a given moment. The general principles of the actuation of the adjustable parts of the power plant are also discussed" (p. 1).
Date: April 1947
Creator: Kühl, H.
Item Type: Refine your search to only Report
open access

Heat Transfer of Airfoils and Plates

Description: "The few available test data on the heat dissipation of wholly or partly heated airfoil models are compared with the corresponding data for the flat plate as obtained by an extension of Prandtl's momentum theory, with differentiation between laminar and turbulent boundary layer and transitional region between both, the extent and appearance of which depend upon certain critical factors. The satisfactory agreement obtained justifies far-reaching conclusions in respect to other profile forms and … more
Date: April 1943
Creator: Seibert, Otto
Item Type: Refine your search to only Report
open access

Heat Transmission in the Boundary Layer

Description: "In the present paper which deals with the heat transfer between the gas and the wall for large temperature drops and large velocities use is made of the method of Dorodnitsyn of the introduction of a new independent variable, with this difference, however, that the relation between the temperature field (that is, density) and the velocity field in the general case considered is not assumed given but is determined from the solution of the problem. The effect of the compressibility arising from … more
Date: April 1949
Creator: Kalikhman, L. E.
Item Type: Refine your search to only Report
open access

The Influence of the Diameter Ratio on the Characteristics Diagram of the Axial Compressor

Description: With the further development of axial blowers into highly loaded flow machines, the influence of the diameter ratio upon air output and efficiency gains in significance. Clarification of this matter is important for single-stage axial compressors, and is of still greater importance for multistage ones, and particularly for aircraft power plants. Tests with a single-stage axial blower gave a decrease in the attainable maximum pressure coefficient and optimum efficiency as the diameter ratio incr… more
Date: April 1948
Creator: Eckert, B.; Pflüger, F. & Weinig, F.
Item Type: Refine your search to only Report
open access

Investigation of Single Stage Axial Fans

Description: The following investigations are connected with experiments on fans carried out by the author in the Gouttingen Aerodynamic Laboratory within the framework of the preliminary experiments for the new Gouttingen wind-tunnel project. A fan rotor was developed which had very high efficiency at the design point corresponding to moderate pressure and which, in addition, could operate at a proportionally high pressure, rise. To establish the determining operating factors the author carried out extensi… more
Date: April 1944
Creator: Ruden, P.
Item Type: Refine your search to only Report
open access

Investigations on Experimental Impellers for Axial Blowers

Description: "A selection of measurements obtained on experimental impellers for axial blowers will be reported. In addition to characteristic curves plotted for low and for high peripheral velocities, proportions and blade sections for six different blower models and remarks on the design of blowers will be presented" (p. 1).
Date: April 1947
Creator: Encke, W.
Item Type: Refine your search to only Report
open access

Lame's Wave Functions of the Ellipsoid of Revolution

Description: "Lamé's wave functions result by separation of the wave equation in elliptic coordinates and by integration of the ordinary differential equations thus originating. They are a generalization of Lamé's potential functions which originate in the same manner from the potential equation. Lamé's wave functions are applied for boundary value problems of the wave equation for regions of space bounded by surfaces of a system of confocal ellipsoids and hyperboloids" (p. 1).
Date: April 1949
Creator: Meixner, J.
Item Type: Refine your search to only Report
open access

The Lead Susceptibility of Fuels and Its Dependence on the Chemical Composition

Description: The fact that by the use of tetraethyl lead a number of otherwise unsuitable fuels could be made to meet engine requirements was not sufficiently appreciated. While use of tetraethyl lead is limited, the addition of special leaded fuels that increase the octane number is a requirement for many fuels. In this connection, the extent to which the action of tetraethyl lead through the addition of knock-resistant hydrocarbons to the base gasoline is influenced, is quite important. To the elucidation… more
Date: April 1940
Creator: Widmaier, O.
Item Type: Refine your search to only Report
open access

The Load Distribution in Bolted or Riveted Joints in Light-Alloy Structures

Description: "This report contains a theoretical discussion of the load distribution in bolted or riveted joints in light-alloy structures which is applicable not only for loads below the limit of proportionality but also for loads above this limit. The theory is developed for double and single shear joints. The methods given are illustrated by numerical examples and the values assumed for the bolt (or rivet) stiffnesses are based partly on theory and partly on known experimental values" (p. 1).
Date: April 1947
Creator: Vogt, F.
Item Type: Refine your search to only Report
open access

[Memorandums on the Subject of Wind Tunnel Measurements of the Henschel Missile "Zitterrochen"]

Description: "At the request of the Henschel Aircraft Works. A. G. Berlin. three models of the missile "Zitterrochen" were investigated at subsonic velocities.(open jet 215-millimeter diameter) and at supersonic velocities (open jet 110 by 130 millimeters) in order to determine the effect of various wing forms on the air forces and moments. Three-component measurements were taken, and one model was also investigated with deflected control plates" (p. 1).
Date: April 1948
Creator: Weber & Kehl
Item Type: Refine your search to only Report
open access

A New Apparatus for Measuring the Temperature at Machine Parts Rotating at High Speeds

Description: "After a brief survey of the available methods for measuring the temperatures of machine parts at high speed, in particular turbine blades and rotors, an apparatus is described which is constructed on the principle of induction. Transmission of the measuring current by sliding contacts therefore is avoided. Up-to-date experiments show that it is possible to give the apparatus a high degree of sensitivity and accuracy" (p. 1).
Date: April 1945
Creator: Gnam, E.
Item Type: Refine your search to only Report
open access

On the Theory of the Laval Nozzle

Description: "In the present paper, the motion of a gas in a plane-parallel Laval nozzle in the neighborhood of the transition from subsonic to supersonic velocities is studied. In a recently published paper, F. I. Frankl, applying the holograph method of Chaplygin, undertook a detailed investigation of the character of the flow near the line of transition from subsonic to supersonic velocities. From the results of Tricomi's investigation on the theory of differential equations of the mixed elliptic-hyperbo… more
Date: April 1949
Creator: Falkovich, S. V.
Item Type: Refine your search to only Report
Back to Top of Screen