NACA Conference on High-Speed Aerodynamics: A Compilation of Papers Presented (open access)

NACA Conference on High-Speed Aerodynamics: A Compilation of Papers Presented

A reproduction of the technical papers presented by staff members of the NACA Laboratories at the NACA Conference on High-Speed Aerodynamics at the Ames Aeronautical Laboratory during March 18-20, 1958. The primary purpose of the conference was to convey to military services and contractors the results of recent research and to provide an opportunity to discuss the results.
Date: 1958-03-18/1958-03-20
Creator: unknown
System: The UNT Digital Library
The Interaction of a Reflected Shock Wave with the Boundary Layer in a Shock Tube (open access)

The Interaction of a Reflected Shock Wave with the Boundary Layer in a Shock Tube

"Ideally, the reflection of a shock from the closed end of a shock tube provides, for laboratory study, a quantity of stationary gas at extremely high temperature. Because of the action of viscosity, however, the flow in the real case is not one-dimensional, and a boundary layer grows in the fluid following the initial shock wave. In this paper simplifying assumptions are made to allow an analysis of the interaction of the shock reflected from the closed end with the boundary layer of the initial shock afterflow. The analysis predicts that interactions of several different types will exist in different ranges of initial shock Mach number" (p. 1).
Date: March 1958
Creator: Mark, Herman
System: The UNT Digital Library
Investigation of Aperiodic Time Processes With Autocorrelation and Fourier Analysis (open access)

Investigation of Aperiodic Time Processes With Autocorrelation and Fourier Analysis

"Autocorrelation and frequency analyses of a series of aperiodic time events, in particular, filtered noises and sibilant sounds, were made. The position and band width of the frequency ranges are best obtained from the frequency analysis, but the energies contained in the several bands are most easily obtained from the autocorrelation function. The mean number of zero crossings of the time function was determined from the curvature of the latter function in the vicinity of the zero crossing, and also with the aid of a decimal counter. The second method was found to be more exact" (p. 1).
Date: March 1958
Creator: Exner, Marie Luise
System: The UNT Digital Library
NACA Conference on Aircraft Loads, Structures, and Flutter (open access)

NACA Conference on Aircraft Loads, Structures, and Flutter

"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 research results and to provide those attending an opportunity to discuss the results" (p. 6).
Date: March 5, 1957
Creator: unknown
System: The UNT Digital Library
A Flat Wing With Sharp Edges in a Supersonic Stream (open access)

A Flat Wing With Sharp Edges in a Supersonic Stream

A basic treatment is given for the approximate solution of the problem of two-dimensional supersonic flow past a thin wing at small angles of attack. The pressure distribution at the surface, the lifting force, and the wave drag are determined.
Date: March 1956
Creator: Donov, A. E.
System: The UNT Digital Library
Formation of a Vortex at the Edge of a Plate (open access)

Formation of a Vortex at the Edge of a Plate

The flow about the plate of infinite width may be represented as a potential flow with discontinuity surfaces which extend from the plate edges. On the basis of a similitude requirement one succeeds in finding a solution of this problem for the plate of infinite width which is correct for the very beginning of the motion of the fluid. Starting from this solution, the further development of the vortex distribution and shape of the surface are observed in the case of a plate of finite width.
Date: March 1956
Creator: Anton, Leo
System: The UNT Digital Library
Interim Report on Fatigue Characteristics of a Typical Metal Wing (open access)

Interim Report on Fatigue Characteristics of a Typical Metal Wing

Constant amplitude fatigue tests of seventy-two P-51D "Mustang" wings are reported. The tests were performed by a vibrational loading system and by an hydraulic loading device for conditions with and without varying amounts of pre-load. The results indicate that: (a) the frequency of occurrence of fatigue at any one location is related to the range of the loads applied, (b) the rate of propagation of visible cracks is more or less constant for a large portion of the life of the specimen, and (c) the fatigue strength of the structure is similar to that of notched material having a theoretical stress concentration factor of more than 3.0.
Date: March 1956
Creator: Kepert, J. L. & Payne, A. O.
System: The UNT Digital Library
On the Buckling of Bars and Plates in the Plastic Range: Part 2 (open access)

On the Buckling of Bars and Plates in the Plastic Range: Part 2

A review is made of existing literature concerning comparison with experiment of various theoretical formulas for buckling of plates in the plastic region. The significance and relative merits of various theories are discussed.
Date: March 1956
Creator: Benthem, J. P.
System: The UNT Digital Library
On the Gas Dynamics of a Rotating Impeller (open access)

On the Gas Dynamics of a Rotating Impeller

It is shown that for a compressible flow with constant entropy the pressure rise maintains the direct relation to the circulation around the blades existing for incompressible flow. In contrast, however, the torque, and with it the power consumption, is increased because of sound waves traveling to infinity already at subsonic circumferential speeds.
Date: March 1956
Creator: Busemann, Adolf
System: The UNT Digital Library
Steady Properly-Banked Turns of Turbojet-Propelled Airplanes (open access)

Steady Properly-Banked Turns of Turbojet-Propelled Airplanes

"The problem of a jet-propelled airplane held in a steady turn is treated both in the very general case and also in the particular case when the polar curve can be approximated by a parabola. Once the general solution has been obtained, some typical maneuvers are next studied such as, the turn of maximum bank, of maximum angular velocity, and of minimum radius of curvature. After a brief comparison is made between the turning characteristics of conventional airplanes and jet airplanes, and after the effect of compressibility upon the turn is examined, the effects of the salient aerodynamic and structural parameters upon the behavior of the plane in curvilinear flight are summarized in the conclusions" (p. 1).
Date: March 1955
Creator: Miele, Angelo
System: The UNT Digital Library
Heat Transfer, Diffusion, and Evaporation (open access)

Heat Transfer, Diffusion, and Evaporation

Memorandum presenting an investigation of the equations that relate heat transfer, diffusion, and evaporation. The report shows that more accurate equations must be substituted for those used in previous investigations of the relation between the quantity of matter exchanged by diffusion and the quantity of heat transferred by conduction.
Date: March 1954
Creator: Nusselt, Wilhelm
System: The UNT Digital Library
Study of the Supersonic Propeller (open access)

Study of the Supersonic Propeller

In this paper a propeller having all sections operating at supersonic speeds is designated a supersonic propeller regardless of flight speed. Analyses assume subsonic flight speeds but very high rotational speeds. A very elementary analysis of the efficiency of a jet-propeller system is presented. A propeller analysis based on conventional vortex blade element theory is presented and reduced to a single point method which leads to an expression for optimum advance ratio in terms of hub-tip diameter ratio and airfoil fineness ratio.
Date: March 1953
Creator: Fabri, Jean & Siestrunck, Raymond
System: The UNT Digital Library
Development of a Laminar Boundary Layer Behind a Suction Point (open access)

Development of a Laminar Boundary Layer Behind a Suction Point

Memorandum presenting an investigation of boundary-layer suction and its favorable effect in deferring transition points as long as possible in order to avoid turbulence.
Date: March 1952
Creator: Wuest, W.
System: The UNT Digital Library
Development of a Laminar Boundary Layer Behind a Suction Point (open access)

Development of a Laminar Boundary Layer Behind a Suction Point

A theoretical investigation is made of the development of a laminar boundary layer behind a suction slot that is assumed to cut off part of the boundary layer without exerting any sink effect. The development, which is approximate, is based on the heat conduction equation. The heat conduction equation enters the analysis through a linearization of the Prandtl-Mises form of the boundary-layer equation.
Date: March 1952
Creator: Wuest, Walter
System: The UNT Digital Library
Friction and Wear (open access)

Friction and Wear

From the practical point of view, this analysis shows that each problem of friction or wear requires its particular solution. There is no universal solution; one or other of the factors predominates and defines the choice of the solution. In certain cases, copper alloys of great thermal conductivity are preferred; in others, plastics abundantly supplied with water. Sometimes, soft antifriction metals are desirable to distribute the load; at other times, hard metals with high resistance to abrasion or heat.
Date: March 1952
Creator: Pomey, Jacques
System: The UNT Digital Library
Calculation of the Bending Stresses in Helicopter Rotor Blades (open access)

Calculation of the Bending Stresses in Helicopter Rotor Blades

A comparatively rapid method is presented for determining theoretically the bending stresses of helicopter rotor blades in forward flight. The method is based on the analysis of the properties of a vibrating beam, and its uniqueness lies in the simple solution of the differential equation which governs the motion of the bent blades.
Date: March 1951
Creator: de Guillenchmidt, P.
System: The UNT Digital Library
Correction Factors for Wind Tunnels of Elliptic Section With Partly Open and Partly Closed Test Section (open access)

Correction Factors for Wind Tunnels of Elliptic Section With Partly Open and Partly Closed Test Section

Jet boundary corrections for partly open and partly closed elliptical wind tunnels for the cases of one and two solid wall segments are presented. Also presented are the combinations of model span and extent of the solid portion of the tunnel wall for which the average correction factor is zero.
Date: March 1951
Creator: Riegels, Fritz W.
System: The UNT Digital Library
Critical Velocities of Ultracentrifuges (open access)

Critical Velocities of Ultracentrifuges

The Euler equations for the rotation of a solid body are applied to the problem of the motion of ultracentrifuges. Particular attention is paid to the problem of the passage of an ultracentrifuge rotor through the critical velocity. The factors that affect the passage of rotors through the critical point are stressed.
Date: March 1951
Creator: Sokolov, V. I.
System: The UNT Digital Library
State and Development of Flutter Calculation (open access)

State and Development of Flutter Calculation

This report discusses the need for considering a wide variation in certain of the basic flutter parameters in conducting a flutter analysis. Conclusions are drawn stating that design charts or simple rules may be misleading. Due to inherent difficulties, dynamic model testing may also yield misleading results. The general flutter equations and various methods of solution are discussed. Of particular interest, curves are presented showing computational effort plotted against a number of degrees of freedom used in a flutter analysis.
Date: March 1951
Creator: Teichmann, Alfred
System: The UNT Digital Library
Two-Dimensional Symmetrical Inlets With External Compression (open access)

Two-Dimensional Symmetrical Inlets With External Compression

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 is developed and illustrated by numerical examples. Intermediary forms between inlets with internal and external compression which can be derived from the latter are briefly discussed.
Date: March 1950
Creator: Ruden, P.
System: The UNT Digital Library
An Approximate Method for Calculation of the Laminar Boundary Layer with Suction for Bodies of Arbitrary Shape (open access)

An Approximate Method for Calculation of the Laminar Boundary Layer with Suction for Bodies of Arbitrary Shape

From Summary: "Various ways were tried recently to decrease the friction drag of a body in a flow; they all employ influencing the boundary layer. One of them consists in keeping the boundary layer Laminar by suction; promising tests have been carried out. Since for large Reynolds numbers the friction drag of the laminar boundary layer is much lower than that of the turbulent boundary layer, a considerable saving in drag results from keeping the boundary layer laminar, even with the blower power required for suction taken into account."
Date: March 1949
Creator: Schlichting, H.
System: The UNT Digital Library
Calculation of Counterrotating Propellers (open access)

Calculation of Counterrotating Propellers

"A method for calculation of a counterrotating propeller which is similar to Walchner's method for calculation of the single propeller in the free air stream is developed and compared with measurements. Several dimensions which are important for the design are given end simple formulas for the gain in efficiency derived. Finally a survey of the behavior of the propeller for various operating conditions is presented" (p. 1).
Date: March 1949
Creator: Ginzel, F.
System: The UNT Digital Library
The Characteristics Method Applied to Stationary Two-Dimensional and Rotationally Symmetrical Gas Flows (open access)

The Characteristics Method Applied to Stationary Two-Dimensional and Rotationally Symmetrical Gas Flows

"By means of characteristics theory, formulas for the numerical treatment of stationary compressible supersonic flows for the two-dimensional and rotationally symmetrical cases have been obtained from their differential equations" (p. 1).
Date: March 1949
Creator: Pfeiffer, F. & Meyer-König, W.
System: The UNT Digital Library
The Compressible Flow Past Various Plane Profiles Near Sonic Velocity (open access)

The Compressible Flow Past Various Plane Profiles Near Sonic Velocity

"In an earlier report UM No.1117 by Gothert,the single-source method was applied to the compressible flow around circles, ellipses, lunes, and around an elongated body of revolution at different Mach numbers and the results compared as far as possible with the calculations by Lamla ad Busemann. Essentially, it was found that with favorable source arrangement the single-source method is in good agreement with the calculations of the same degree of approximation by Lamla and Busemann. Near sonic velocity the number of steps must be increased considerably in order to sufficiently approximate the adiabatic curve" (p. 1).
Date: March 1949
Creator: Göthert, B. & Kawalki, K. H.
System: The UNT Digital Library