UNT Libraries Government Documents Department - 29 Matching Results

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A study of the motion and aerodynamic heating of ballistic missiles entering the earth's atmosphere at high supersonic speeds

Description: From Summary: "A simplified analysis of the velocity and deceleration history of ballistic missiles entering the earth's atmosphere at high supersonic speeds is presented. The results of this motion analysis are employed to indicate means available to the designer for minimizing aerodynamic heating. The heating problem considered involves not only the total heat transferred to a missile by convection, but also the maximum average and local time rates of convective heat transfer."
Date: April 28, 1953
Creator: Allen, H. Julian & Eggers, A. J., Jr.
Item Type: Refine your search to only Report
open access

The design of fins for air-cooled cylinders

Description: From Summary: "An analysis was made to determine the proportions of fins made of aluminum, copper, magnesium, and steel necessary to dissipate maximum quantities of heat for different fin widths, fin weights, and air-flow conditions. The analysis also concerns the determination of the optimum fin proportions when specified limits are placed on the fin dimensions. The calculation of the heat flow in the fins is based on experimentally verified, theoretical equations. The surface heat-transfer co… more
Date: June 28, 1939
Creator: Biermann, Arnold E. & Ellerbrock, Herman H., Jr.
Item Type: Refine your search to only Report
open access

Aircraft Accidents: Method of Analysis

Description: The revised report includes the chart for the analysis of aircraft accidents, combining consideration of the immediate causes, underlying causes, and results of accidents, as prepared by the special committee, with a number of the definitions clarified. A brief statement of the organization and work of the special committee and of the Committee on Aircraft Accidents; and statistical tables giving a comparison of the types of accidents and causes of accidents in the military services on the one … more
Date: January 28, 1930
Creator: Committee on Aircraft Accidents
Item Type: Refine your search to only Report
open access

Flame Speeds and Energy Considerations for Explosions in a Spherical Bomb

Description: "Simultaneous measurements were made of the speed of flame and the rise in pressure during explosions of mixtures of carbon monoxide, normal heptane, iso-octane, and benzene in a 10-inch spherical bomb with central ignition. From these records, fundamental properties of the explosive mixtures, which are independent of the apparatus, were computed. The transformation velocity, or speed at which flame advances into and transforms the explosive mixture, increases with both the temperature and the … more
Date: September 28, 1939
Creator: Fiock, Ernest F.; Marvin, Charles F., Jr.; Caldwell, Frank R. & Roeder, Carl H.
Item Type: Refine your search to only Report
open access

Pressure-distribution measurements on the hull and fins of scale model of the U. S. Airship "Akron"

Description: This report presents the results of measurements of pressure distribution conducted in the propeller-research wind tunnel of the National Advisory Committee for Aeronautics on a 1/40-scale model of the U. S. Airship "Akron" (ZRS-4). The pressures, which were measured simultaneously at nearly 400 orifices located at 26 stations along one side of the hull, were recorded by two photographic multiple manometers placed inside the model. The hull pressures were measured both with and without the tail… more
Date: June 28, 1932
Creator: Freeman, Hugh B.
Item Type: Refine your search to only Report
open access

On some reciprocal relations in the theory of nonstationary flows

Description: In the theory of nonstationary flows about airfoils, the "indicial lift" function ksub1(s) of Wagner and the "alternating lift" function c(k) of Theodorsen have fundamental significance. This paper reports on some interesting relations of the nature of Fourier transforms that exist between these functions. General problems in transient flows about airfoils may be given a unified broad treatment when these functions are employed. Certain approximate results also are reported which are of notable… more
Date: March 28, 1938
Creator: Garrick, I. E.
Item Type: Refine your search to only Report
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Pressure distribution over NACA 23012 airfoil with a slotted and a split flap

Description: A pressure-distribution investigation has been conducted in the NACA 4 by 6-foot vertical wind tunnel to determine the air loads on an NACA 23012 airfoil in combination with a 25.66-percent-chord slotted flap and a 20-percent-chord split flap. Pressures were measured on both the upper and the lower surfaces of the main airfoil and the flaps for several angles of attack and at several flap settings. The data, presented as pressure diagrams and as graphs of the section coefficients for the flap a… more
Date: May 28, 1940
Creator: Harris, Thomas A. & Lowry, John G.
Item Type: Refine your search to only Report
open access

The Calculation of Pressure on Slender Airplanes in Subsonic and Supersonic Flow

Description: "Under the assumption that a wing, body, or wing-body combination is slender or flying at near sonic velocity, expressions are given which permit the calculation of pressure in the immediate vicinity of the configuration. The disturbance field, in both subsonic and supersonic flight, is shown to consist of two-dimensional disturbance fields extending laterally and a longitudinal field that depends on the streamwise growth of cross-sectional area. A discussion is also given of couplings, between… more
Date: November 28, 1953
Creator: Heaslet, Max A. & Lomax, Harvard
Item Type: Refine your search to only Report
open access

Investigation of damping liquids for aircraft instruments 2

Description: "Data are presented on the kinematic viscosity, in the temperature range -50 degrees to +30 degrees C. of pure liquids and of solutions of animal oils, vegetable oils, mineral oils, glycerine, and ethylene glycol in various low freezing point solvents. It is shown that the thermal coefficient of kinematic viscosity as a function of the kinematic viscosity of the solutions of glycerine and ethylene glycol in alcohols is practically independent of the temperature and the chemical composition of t… more
Date: March 28, 1931
Creator: Houseman, M. R. & Keulegan, G. H.
Item Type: Refine your search to only Report
open access

Development of craze and impact resistance in glazing plastics by multiaxial stretching

Description: The loss of strength of cast polymethyl methacrylate plastic as a result of crazing is of considerable importance to the aircraft industry. Because of the critical need for basic information on the nature of crazing and the effects of various treatments and environmental conditions on its incidence and magnitude, an investigation of this phenomenon was undertaken. The following factors were examined: (1) the effect of stress-solvent crazing on tensile strength of polymethyl methacrylate; (2) th… more
Date: December 28, 1955
Creator: Kline, G. M.; Wolock, I.; Axilrod, B. M.; Sherman, M. A.; George, D. A. & Cohen, V.
Item Type: Refine your search to only Report
open access

The Structure of Turbulence in Fully Developed Pipe Flow

Description: "Measurements, principally with a hot-wire anemometer, were made in fully developed turbulent flow in a 10-inch pipe at speeds of approximately 10 and 100 feet per second. Emphasis was placed on turbulence and conditions near the wall. The results include relevant mean and statistical quantities, such as Reynolds stresses, triple correlations, turbulent dissipation, and energy spectra" (p. 1).
Date: October 28, 1952
Creator: Laufer, John
Item Type: Refine your search to only Report
open access

On Traveling Waves in Beams

Description: "The basic equations of Timoshenko for the motion of vibrating nonuniform beams, which allow for effects of transverse shear deformation and rotary inertia, are presented in several forms, including one in which the equations are written in the directions of the characteristics. The propagation of discontinuities in moment and shear, as governed by these equations, is discussed. Numerical traveling-wave solutions are obtained for some elementary problems of finite uniform beams for which the pr… more
Date: October 28, 1952
Creator: Leonard, Robert W. & Budiansky, Bernard
Item Type: Refine your search to only Report
open access

Investigations of Effects of Surface Temperature and Single Roughness Elements on Boundary-Layer Transition

Description: "The laminar boundary layer and the position of the transition point were investigated on a heated flat plate. It was found that the Reynolds number of transition decreased as the temperature of the plate is increased. It is shown from simple qualitative analytical considerations that the effect of variable viscosity in the boundary layer due to the temperature difference produces a velocity profile with an inflection point if the wall temperature is higher than the free-stream temperature" (p.… more
Date: August 28, 1946
Creator: Liepmann, Hans W. & Fila, Gertrude H.
Item Type: Refine your search to only Report
open access

Chordwise and Compressibility Corrections to Slender-Wing Theory

Description: Corrections to slender-wing theory are obtained by assuming a spanwise distribution of loading and determining the chordwise variation which satisfies the appropriate integral equation. Such integral equations are set up in terms of the given vertical induced velocity on the center line or, depending on the type of wing plan form, its average value across the span at a given chord station. The chordwise distribution is then obtained by solving these integral equations. Results are shown for fla… more
Date: November 28, 1952
Creator: Lomax, Harvard & Sluder, Loma
Item Type: Refine your search to only Report
open access

The Crinkling Strength and the Bending Strength of Round Aircraft Tubing

Description: "The upper limit of the column strength of structural members composed of thin material is the maximum axial stress such members can carry when short enough to fail locally, by crinkling. This stress is a function of the mechanical properties of the material and of the geometrical shape of the cross section. The bending strength, as measured by the modulus of rupture, of structural members is also a function of these same variables. Tests were made of round tubes of chromium-molybdenum steel an… more
Date: March 28, 1938
Creator: Osgood, William R.
Item Type: Refine your search to only Report
open access

Investigation of the drag of various axially symmetric nose shapes of fineness ratio 3 for Mach numbers from 1.24 to 7.4

Description: Experimental drag measurements at zero angle of attack for various theoretical minimum drag nose shapes, hemispherically blunted cones, and other more common profiles of fineness ratios of about 3 are compared with theoretical results for a Mach number and Reynolds number range of 1.24 to 7.4 and 1.0 x 10 to the 6th power to 7.5 x 10 to the 6th power (based on body length), respectively. The results of experimental pressure-distribution measurements are used for the development of an empirical … more
Date: August 28, 1952
Creator: Perkins, Edward W.; Jorgensen, Leland H. & Sommer, Simon C.
Item Type: Refine your search to only Report
open access

An analysis of life expectancy of airplane wings in normal cruising flight

Description: From Summary: "In order to provide a basis for judging the relative importance of wing failure by fatigue and by single intense gusts, an analysis of wing life for normal cruising flight was made based on data on the frequency of atmospheric gusts. The independent variables considered in the analysis included stress-concentration factor, stress-load relation, wing loading, design and cruising speeds, design gust velocity, and airplane size. Several methods for estimating fatigue life from gust … more
Date: May 28, 1945
Creator: Putnam, Abbott A.
Item Type: Refine your search to only Report
open access

Contributions on the Mechanics of Boundary-Layer Transition

Description: "The manner in which flow in a boundary layer becomes turbulent was investigated on a flat plate at wind speeds generally below 100 feet per second. Hot-wire techniques were used, and many of the results are derived from oscillograms of velocity fluctuations in the transition region. Following a presentation of the more familiar aspects of transition, there are presented the very revealing facts discovered while studying the characteristics of artificially produced turbulent spots" (p. 853).
Date: February 28, 1955
Creator: Schubauer, G. B. & Klebanoff, P. S.
Item Type: Refine your search to only Report
open access

Free-spinning wind-tunnel tests of a low-wing monoplane with systematic changes in wings and tails IV: effect of center-of-gravity location

Description: Eight wings and three tails, covering a wide range of aerodynamic characteristics, were independently ballasted so as to be interchangeable with no change in mass distribution. For each of the 24 resulting wing-tail combinations, observations were made of the steady spin for four control settings and of recoveries for five control manipulations. The results are presented in the form of charts comparing the spin characteristics. The tests are part of a general investigation being made in the NAC… more
Date: March 28, 1939
Creator: Seidman, Oscar & Neihouse, A. I.
Item Type: Refine your search to only Report
open access

Wind-Tunnel Interference With Particular Reference to Off-Center Positions of the Wing and to the Downwash at the Tail

Description: "The theory of wind tunnel boundary influence on the downwash from a wing has been extended to provide more complete corrections for application to airplane test data. The first section of the report gives the corrections of the lifting line for wing positions above or below the tunnel center line; the second section shows the manner in which the induced boundary influence changes with distance aft of the lifting line. Values of the boundary corrections are given for off-center positions of the… more
Date: June 28, 1935
Creator: Silverstein, Abe & White, James A.
Item Type: Refine your search to only Report
open access

The N.A.C.A. High-Speed Wind Tunnel and Tests of Six Propeller Sections

Description: "This report gives a description of the high-speed wind tunnel of the National Advisory Committee for Aeronautics. The operation of the tunnel is also described and the method of presenting the data is given. An account of an investigation of the aerodynamic properties of six propeller sections is included" (p. 399).
Date: March 28, 1933
Creator: Stack, John
Item Type: Refine your search to only Report
open access

Tests of 16 related airfoils at high speed

Description: From Summary: "In order to provide information that might lead to the development of better propeller section, 13 related symmetrical airfoils were tested in the NACA high-speed wind tunnel for a study of the effect of thickness form on the aerodynamic characteristics. The thickness-form variables studies were the value of the maximum thickness, the position along the chord at which the maximum thickness occurs, and the value of the leading-edge radius. The tests were conducted through the low … more
Date: April 28, 1934
Creator: Stack, John & von Doenhoff, Albert E.
Item Type: Refine your search to only Report
open access

A theoretical analysis of the effect of time lag in an automatic stabilization system on the lateral oscillatory stability of an airplane

Description: "A method is presented for determining the effect of time lag in an automatic stabilization system on the lateral oscillatory stability of an airplane. The method is based on an analytical-graphical procedure. The critical time lag of the airplane-autopilot system is readily determined from the frequency-response analysis. The method is applied to a typical present-day airplane equipped with an automatic pilot sensitive to yawing acceleration and geared to the rudder so that rudder control is a… more
Date: October 28, 1949
Creator: Sternfield, Leonard & Gates, Ordway B., Jr.
Item Type: Refine your search to only Report
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