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Airfoil section characteristics as affected by protuberances

Description: From Introduction: "The present report deals with another phase of the investigation; that is, the effects on airfoil section characteristics of protuberances extending along the entire span from the airfoil surface."
Date: July 11, 1932
Creator: Jacobs, Eastman N.
Partner: UNT Libraries Government Documents Department
open access

Analysis of Heat and Compressibility Effects in Internal Flow Systems and High-Speed Tests of a Ram-Jet System

Description: Report discussing an analysis has been made by the NACA of the effects of heat and compressibility in the flow through the internal systems of aircraft along with equations and charts are developed whereby the flow characteristics at key stations in a typical internal system may be readily obtained.
Date: July 21, 1942
Creator: Becker, John V. & Baals, Donald D.
Partner: UNT Libraries Government Documents Department
open access

Analysis of Jet-Propulsion-Engine Combustion-Chamber Pressure Losses

Description: From Summary: "The development and the use of a chart for estimating the pressure losses in jet-engine combustion chambers are described. By means of the chart, the pressure losses due to fluid friction and to momentum changes in the air flow accompanying combustion can be separately evaluated. The over-all pressure losses computed from the pressure-loss chart are within 7 percent of the experimental values for the three types of combustion chambers considered herein."
Date: July 31, 1946
Creator: Pinkel, I. Irving & Shames, Harold
Partner: UNT Libraries Government Documents Department
open access

Analysis of Turbulent Free-Convection Boundary Layer on Flat Plate

Description: "With the use of Karman's integrated momentum equation for the boundary layer and data on the wall-shearing stress and heat transfer in forced-convection flow, a calculation was carried out for the flow and heat transfer in the turbulent free-convection boundary layer on a vertical flat plate. The calculation is for a fluid with a Prandtl number that is close to 1. A formula was derived for the heat-transfer coefficient that was in good agreement with experimental data in the range of Grashof n… more
Date: July 12, 1950
Creator: Eckert, E. R. G. & Jackson, Thomas W.
Partner: UNT Libraries Government Documents Department
open access

The application of the statistical theory of extreme values to gust-load problems

Description: From Introduction: "Recent developments in the statistical theory of extreme values (references 4 to 10) have indicated a somewhat more rational approach to the problem of predicting the probability of occurrence The present report summarizes some of these findings, indicates the method of application, and evaluates their applicability to certain gust-load problems ."
Date: July 22, 1949
Creator: Press, Harry
Partner: UNT Libraries Government Documents Department
open access

Characteristics of the Langley 8-Foot Transonic Tunnel With Slotted Test Section

Description: "A large wind tunnel, approximately 8 feet in diameter, has been converted to transonic operation by means of slots in the boundary extending in the direction of flow. The usefulness of such a slotted wind tunnel, already known with respect to the reduction of the subsonic blockage interference and the production of continuously variable supersonic flows, has been augmented by devising a slot shape with which a supersonic test region with excellent flow quality could be produced. Experimental l… more
Date: July 3, 1958
Creator: Wright, Ray H.; Ritchie, Virgil S. & Pearson, Albin O.
Partner: UNT Libraries Government Documents Department
open access

Charts for the Minimum-Weight Design of 24S-T Aluminum-Alloy Flat Compression Panels With Longitudinal Z-Section Stiffeners

Description: "Design charts are developed for 24S-T aluminum-alloy flat compression panels with longitudinal z-section stiffeners. These charts make possible the design of the lightest panels of this type for a wide range of design requirements. Examples of the use of the charts are given and it is pointed out on the basis of these examples that, over a wide range of design conditions, the maintenance of buckle-free surfaces does not conflict with the achievement of high structural efficiency" (p. 553).
Date: July 9, 1945
Creator: Schuette, Evan H.
Partner: UNT Libraries Government Documents Department
open access

Comparison of effectiveness of convection-, transpiration-, and film-cooling methods with air as coolant

Description: From Summary: "Various parts of aircraft propulsion engines that are in contact with hot gases often require cooling. Transpiration and film cooling, new methods that supposedly utilize cooling air more effectively than conventional convection cooling, have already been proposed. This report presents material necessary for a comparison of the cooling requirements of these three methods. Correlations that are regarded by the authors as the most reliable today are employed in evaluating each of t… more
Date: July 9, 1953
Creator: Eckert, E. R. G. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department
open access

Compressibility and Heating Effects on Pressure Loss and Cooling of a Baffled Cylinder Barrel

Description: "Theoretical investigations have shown that, because air is compressible, the pressure-drop requirements for cooling an air-cooled engine will be much greater at high altitudes and high speeds than at sea level and low speeds. Tests were conducted by the NACA to obtain some experimental confirmation of the effect of air compressibility on cooling and pressure loss of a baffled cylinder barrel and to evaluate various methods of analysis. The results reported in the present paper are regarded as … more
Date: July 1, 1944
Creator: Goldstein, Arthur W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
open access

Compressibility and Heating Effects on Pressure Loss and Cooling of a Baffled Cylinder Barrel

Description: "Theoretical investigations have shown that, because air is compressible, the pressure-drop requirements for cooling an air-cooled engine will be much greater at high altitudes and high speeds than at sea level and low speeds. Tests were conducted by the NACA to obtain some experimental confirmation of the effect of air compressibility on cooling and pressure loss of a baffled cylinder barrel and to evaluate various methods of analysis. The results reported in the present paper are regarded as … more
Date: July 1, 1944
Creator: Goldstein, Arthur W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
open access

The Compressibility Burble and the Effect of Compressibility on Pressures and Forces Acting on an Airfoil

Description: "Simultaneous air-flow photographs and pressure-distribution measurements were made of the NACA 4412 airfoil at high speeds to determine the physical nature of the compressibility burble. The tests were conducted in the NACA 24-inch high-speed wind tunnel. The flow photographs were obtained by the Schlieren method and the pressures were simultaneously measured for 54 stations in the 5-inch-chord airfoil by means of a multiple-tube manometer. Following the general program, a few measurements of … more
Date: July 6, 1938
Creator: Stack, John; Lindsey, W. F. & Littell, Robert E.
Partner: UNT Libraries Government Documents Department
open access

Design Charts for Predicting Downwash Angles and Wake Characteristics Behind Plain and Flapped Wings

Description: "Equations and design charts are given for predicting the downwash angles and the wake characteristics for power-off conditions behind plain and flapped wings of the types used in modern design practice. The downwash charts cover the cases of elliptical wings and wings of taper ratios 1, 2, 3, and 5, with aspect ratios of 6, 9, and 12, having flaps covering 0, 40, 70, and 100 percent of the span. Curves of the span load distributions for all these cases are included" (p. 1).
Date: July 14, 1938
Creator: Silverstein, Abe & Katzoff, S.
Partner: UNT Libraries Government Documents Department
open access

Design of two-dimensional channels with prescribed velocity distributions along the channel walls

Description: "A general method of design is developed for two-dimensional unbranched channels with prescribed velocities as a function of arc length along the channel walls. The method is developed for both compressible and incompressible, irrotational, nonviscous flow and applies to the design of elbows, diffusers, nozzles, and so forth. In part I solutions are obtained by relaxation methods; in part II solutions are obtained by a Green's function. Five numerical examples are given in part I including thre… more
Date: July 25, 1951
Creator: Stanitz, John D.
Partner: UNT Libraries Government Documents Department
open access

Dynamics of a turbojet engine considered as a quasi-static system

Description: From Summary: "A determination of the dynamic characteristics of a typical turbojet engine with a centrifugal compressor, a sonic-flow turbine-nozzle diaphragm, and fixed area exhaust nozzle is presented. A generalized equation for transient behavior of the engine was developed; this equation was then verified by calculations using compressor and turbine performance charts extrapolated from equilibrium operating data and by experimental data obtained from an engine operated under transients in … more
Date: July 27, 1949
Creator: Otto, Edward W. & Taylor, Burt L., III
Partner: UNT Libraries Government Documents Department
open access

The Effect of Increased Cooling Surface on Performance of Aircraft-Engine Cylinders as Shown by Tests of the NACA Cylinder

Description: A method of constructing fins of nearly optimum proportions has been developed by the NACA to the point where a cylinder has been manufactured and tested. Data were obtained on cylinder temperature for a wide range of inlet-manifold pressures, engine speeds, and cooling-pressure differences. The results indicate that an improvement of 40 percent in the outside-wall heat-transfer coefficient could be realized on the present NACA cylinder by providing a thermal bond equivalent to that of an integ… more
Date: July 1, 1944
Creator: Schey, Oscar W.; Rollin, Vern G. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
open access

The effect of mass distribution on the lateral stability and control characteristics of an airplane as determined by tests of a model in the free-flight tunnel

Description: The effects of mass distribution on lateral stability and control characteristics of an airplane have been determined by flight tests of a model in the NACA free-flight tunnel. In the investigation, the rolling and yawing moments of inertia were increased from normal values to values up to five times normal. For each moment-of-inertia condition, combinations of dihedral and vertical-tail area representing a variety of airplane configurations were tested. The results of the flight tests of the m… more
Date: July 20, 1943
Creator: Campbell, John P. & Seacord, Charles L., Jr.
Partner: UNT Libraries Government Documents Department
open access

Effect of variation of chord and span of ailerons on rolling and yawing moments in level flight

Description: This report presents the results of an investigation of the rolling and yawing moments due to ailerons of various chords and spans on two airfoils having the Clark Y and U. S. A. 27 wing sections. Some attention is devoted to a study of the effect of scale on rolling and yawing moments and to the effect of slightly rounding the wing tips. The results apply to level flight with the wing chord set at an angle of attack of +4 degrees and to conditions of zero pitch, zero yaw, and zero roll of the … more
Date: July 10, 1928
Creator: Heald, R. H. & Strother, D. H.
Partner: UNT Libraries Government Documents Department
open access

Effects of sweepback on boundary layer and separation

Description: "Following a law of stress adopted in the Navier-Stokes equations, the configuration of the viscous flow in planes at right angles to the axis of an infinite cylinder is found to be independent of the axial motion of the cylinder. In the limiting case of a yawed or swept wing of very high aspect ratio, certain boundary-layer and separation phenomena are thus determined independently by the crosswise component of velocity. It follows that the effect of sweepback is to increase the area of stable… more
Date: July 1947
Creator: Jones, Robert T.
Partner: UNT Libraries Government Documents Department
open access

Elliptic Cones Alone and with Wings at Supersonic Speed

Description: "To help fill the gap in the knowledge of aerodynamics of shapes intermediate between bodies of revolution and flat triangular wings, force and moment characteristics for elliptic cones have been experimentally determined for Mach numbers of 1.97 and 2.94. Elliptic cones having cross-sectional axis ratios from 1 through 6 and with lengths and base areas equal to circular cones of fineness ratios 3.67 and 5 have been studied for angles of bank of 0 degree and 90 degrees. Elliptic and circular co… more
Date: July 17, 1957
Creator: Jorgensen, Leland H.
Partner: UNT Libraries Government Documents Department
open access

Exact solutions of laminar-boundary-layer equations with constant property values for porous wall with variable temperature

Description: From Summary: "Exact solution of the laminar-boundary-layer equations for wedge-type flow with constant property values are presented for transpiration-cooled surfaces with variable wall temperatures. The difference between wall and stream temperature is assumed proportional to a power of the distance from the leading edge. Solutions are given for a Prandtl number of 0.7 and ranges of pressure-gradient, cooling-air-flow, and wall-temperature-gradient parameters. Boundary-layer profiles, dimensi… more
Date: July 15, 1954
Creator: Donoughe, Patrick L. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department
open access

Flight measurements of the dynamic longitudinal stability of several airplanes and a correlation of the measurements with pilots' observations of handling characteristics

Description: The dynamic longitudinal stability characteristics of eight airplanes as defined by the period and damping of the longitudinal oscillations were measured in flight to determine the degree of stability that may be expected in conventional airplanes. An attempt was made to correlate the measured stability with pilots' opinions of the general handling characteristics of the airplanes in order to obtain an indication of the most desirable degree of dynamic stability. The results of the measurements… more
Date: July 15, 1936
Creator: Soulé, Hartley A.
Partner: UNT Libraries Government Documents Department
open access

The Flow of a Compressible Fluid Past a Circular Arc Profile

Description: "The Ackeret iteration process is utilized to obtain higher approximations than that of Prandtl and Glauert for the flow of a compressible fluid past a circular arc profile. The procedure is to expand the velocity potential in a power series of the camber coefficient. The first two terms of the development correspond to the Prandtl-Glauert approximation and yield the well-known correction to the circulation about the profile" (p. 385).
Date: July 15, 1944
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
open access

Full-Scale Wind-Tunnel Tests of a Series of Metal Propellers on a VE-7 Airplane

Description: "An adjustable blade metal propeller was tested at five different angle settings, forming a series varying in pitch. The propeller was mounted on a VE-7 airplane in the twenty-foot propeller research tunnel of the National Advisory Committee for Aeronautics. The efficiencies were found to be from 4 to 7 per cent higher than those of standard wood propellers operating under the same conditions. The results are given in convenient form for use in selecting propellers for aircraft" (p. 521).
Date: July 13, 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department
open access

A high-speed motion-picture study of normal combustion, knock and preignition in a spark-ignition engines

Description: Combustion in a spark-ignition engine was investigated by means of the NACA high-speed motion-picture cameras. This camera is operated at a speed of 40,000 photographs a second and therefore makes possible the study of changes that take place in the intervals as short as 0.000025 second. When the motion pictures are projected at the normal speed of 16 frames a second, any rate of movement shown is slowed down 2500 times. Photographs are presented of normal combustion, of combustion from preigni… more
Date: July 24, 1940
Creator: Rothrock, A. M.; Spencer, R. C. & Miller, Cearcy D.
Partner: UNT Libraries Government Documents Department
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