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Air flow around finned cylinders

Description: Report presents the results of a study made to determine the air-flow characteristics around finned cylinders. Air-flow distribution is given for a smooth cylinder, for a finned cylinder having several fin spacings and fin widths, and for a cylinder with several types of baffle with various entrance and exit shapes. The results of these tests show: that flow characteristics around a cylinder are not so critical to changes in fin width as they are to fin spacing; that the entrance of the baffle … more
Date: November 7, 1935
Creator: Brevoort, M. J. & Rollin, Vern G.
Item Type: Refine your search to only Report
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Air force and moment for N-20 wing with certain cut-outs

Description: From Introduction: "The airplane designer often finds it necessary, in meeting the requirements of visibility, to remove area or to otherwise locally distort the plan or section of an airplane wing. This report, prepared for the Bureau of Aeronautics January 15, 1925, contains the experimental results of tests on six 5 by 30 inch N-20 wing models, cut out or distorted in different ways, which were conducted in the 8 by 8 foot wind tunnel of the Navy Aerodynamical Laboratory in Washington in 192… more
Date: November 29, 1926
Creator: Smith, R. H.
Item Type: Refine your search to only Report
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Analysis of effect of basic design variables on subsonic axial-flow-compressor performance

Description: From Summary: "A blade-element theory for axial-flow compressors has been developed and applied to the analysis of the effects of basic design variables such as Mach number, blade loading, and velocity distribution on compressor performance. The relations among several efficiencies useful in compressor design are derived and discussed. The possible gains in useful operating range obtainable by the use of adjustable stator blades are discussed and a rapid approximate method of calculating blade-… more
Date: November 26, 1947
Creator: Sinnette, John T., Jr.
Item Type: Refine your search to only Report
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An Analysis of Lateral Stability in Power-Off Flight With Charts for Use in Design

Description: "The aerodynamic and mass factors governing lateral stability are discussed and formulas are given for their estimation. Relatively simple relationships between the governing factors and the resulting stability characteristics are presented. A series of charts is included with which approximate stability characteristics may be rapidly estimated" (p. 1).
Date: November 17, 1936
Creator: Zimmerman, Charles H.
Item Type: Refine your search to only Report
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Application of a channel design method to high-solidity cascades and tests of an impulse cascade with 90 degrees of turning

Description: From introduction: "A technique for application of the channel design methods of reference 11 to the design of high-solidity cascades with prescribed velocity distributions as a function of arc length along the blade-element profiles is presented herein."
Date: November 30, 1951
Creator: Stanitz, John D. & Sheldrake, Leonard J.
Item Type: Refine your search to only Report
open access

Application of Spring Tabs to Elevator Controls

Description: Equations are presented for calculating the stick-force characteristics obtained with a spring-tab type of elevator control. The main problems encountered in the design of a satisfactory elevator spring tab are to provide stick forces in the desired range, to maintain the force per g sufficiently constant throughout the speed range, to avoid undesirable "feel" of the control in ground handling or in flight at low airspeeds, and to prevent flutter. Examples are presented to show the design featu… more
Date: November 24, 1944
Creator: Phillips, William H.
Item Type: Refine your search to only Report
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Axially Symmetric Shapes With Minimum Wave Drag

Description: "The external wave drag of bodies of revolution moving at supersonic speeds can be expressed either in terms of the geometry of the body, or in terms of the body-simulating axial source distribution. For purposes of deriving optimum bodies under various given conditions, it is found that the second of the methods mentioned is the more tractable. By use of a quasi-cylindrical theory, that is, the boundary conditions are applied on the surface of a cylinder rather than on the body itself, the var… more
Date: November 22, 1954
Creator: Heaslet, Max A. & Fuller, Franklyn B.
Item Type: Refine your search to only Report
open access

Blower Cooling of Finned Cylinders

Description: "Several electrically heated finned steel cylinders enclosed in jackets were cooled by air from a blower. The effect of the air conditions and fin dimensions on the average surface heat-transfer coefficient q and the power required to force the air around the cylinders were determined. Tests were conducted at air velocities between the fins from 10 to 130 miles per hour and at specific weights of the air varying from 0.046 to 0.074 pound per cubic foot. The fin dimensions of the cylinders cover… more
Date: November 14, 1936
Creator: Schey, Oscar W. & Ellerbrock, Herman H., Jr.
Item Type: Refine your search to only Report
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The calculation of downwash behind supersonic wings with an application to triangular plan forms

Description: A method is developed consistent with the assumptions of small perturbation theory which provides a means of determining the downwash behind a wing in supersonic flow for a known load distribution. The analysis is based upon the use of supersonic doublets which are distributed over the plan form and wake of the wing in a manner determined from the wing loading. The equivalence in subsonic and supersonic flow of the downwash at infinity corresponding to a given load distribution is proved.
Date: November 9, 1948
Creator: Lomax, Harvard; Sluder, Loma & Heaslet, Max A.
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
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Characteristics of Five Propellers in Flight

Description: "This investigation was made for the purpose of determining the characteristics of five full-scale propellers in flight. The equipment consisted of five propellers in conjunction with a VE-7 airplane and a Wright E-2 engine. The propellers were of the same diameter and aspect ratio. Four of them differed uniformly in thickness and pitch and the fifth propeller was identical with one of the other four with exception of a change of the airfoil section" (p. 267).
Date: November 8, 1927
Creator: Crowley, J. W., Jr. & Mixson, R. E.
Item Type: Refine your search to only Report
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Charts for Estimating Performance of High-Performance Helicopters

Description: "Theoretically derived charts showing the profile-drag-thrust ratio are presented for helicopter rotors operating in forward flight and having hinged rectangular blades with a linear twist of 0 degree, 8 degrees, and 16 degrees. The charts, showing the profile-drag characteristics of the rotor for various combinations of pitch angle, ratio of thrust coefficient to solidity, and a parameter representing shaft power input, are presented for tip-speed ratios ranging from 0.05 to 0.50. Also present… more
Date: November 23, 1955
Creator: Gessow, Alfred & Tapscott, Robert J.
Item Type: Refine your search to only Report
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Charts for the Determination of Wing Torsional Stiffness Required for Specified Rolling Characteristics or Aileron Reversal Speed

Description: From Summary :"A series of charts are presented by which the wing torsional stiffness required to meet a given standard of rolling effectiveness may be quickly determined. The charts may also be used to obtain quickly the aileron reversal speed and the variation of the loss in rolling effectiveness with airspeed. The charts apply to linearly tapered wings and elliptical wings of tubular-shell construction having various aspect ratios with aileron span and location of ailerons as variables. In t… more
Date: November 9, 1944
Creator: Pearson, Henry A. & Aiken, William S., Jr.
Item Type: Refine your search to only Report
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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

Cloud-droplet ingestion in engine inlets with inlet velocity ratios of 1.0 and 0.7

Description: From Summary: "The paths of cloud droplets into two engine inlets have been calculated for a wide range of meteorological and flight conditions. The amount of water in droplet form ingested by the inlets and the amount and distribution of water impinging on the inlet walls are obtained from these droplet-trajectory calculations. In both types of inlet, a prolate ellipsoid of revolution represents either part or all of the forebody at the center of an annular inlet to an engine. The configuratio… more
Date: November 2, 1955
Creator: Brun, Rinaldo J.
Item Type: Refine your search to only Report
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Comparison of Alcogas Aviation Fuel With Export Aviation Gasoline

Description: Mixtures of gasoline and alcohol when used in internal combustion engines designed for gasoline have been found to possess the advantage of alcohol in withstanding high compression without "knock" while retaining advantages of gasoline with regard to starting characteristics. Test of such fuels for maximum power-producing ability and fuel economy at various rates of consumption are thus of practical importance, with especial reference to high-compression engine development. This report discusse… more
Date: November 25, 1919
Creator: Gage, V. R.; Sparrow, S. W. & Harper, D. R.
Item Type: Refine your search to only Report
open access

A comparison of the experimental subsonic pressure distributions about several bodies of revolution with pressure distributions computed by means of the linearized theory

Description: "An analysis is made of the effects of compressibility on the pressure coefficients about several bodies of revolution by comparing experimentally determined pressure coefficients with corresponding pressure coefficients calculated by the use of the linearized equations of compressible flow. The results show that the theoretical methods predict the subsonic pressure-coefficient changes over the central part of the body but do not predict the pressure-coefficient changes near the nose. Extrapola… more
Date: November 5, 1951
Creator: Matthews, Clarence W.
Item Type: Refine your search to only Report
open access

Compressible Flow About Symmetrical Joukowski Profiles

Description: "The method of Poggi is employed for the determination of the effects of compressibility upon the flow past an obstacle. A general expression for the velocity increment due to compressibility is obtained. The general result holds whatever the shape of the obstacle; but, in order to obtain the complete solution, it is necessary to know a certain Fourier expansion of the square of the velocity of flow past the obstacle. An application is made to the case flow of a symmetrical Joukowski profile wi… more
Date: November 19, 1937
Creator: Kaplan, Carl
Item Type: Refine your search to only Report
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Correlation of the drag characteristics of a typical pursuit airplane obtained from high-speed wind-tunnel and flight tests

Description: In order to obtain a correlation of drag data from wind-tunnel and flight tests at high Mach numbers, a typical pursuit airplane, with the propeller removed, was tested in flight at Mach numbers up to 0.755, and the results were compared with wind-tunnel tests of a 1/3-scale model of the airplane. The tests results show that the drag characteristics of the test airplane can be predicted with satisfactory accuracy from tests in the Ames 16-foot high-speed wind tunnel of the Ames Aeronautical Lab… more
Date: November 2, 1944
Creator: Nissen, James M.; Gadeberg, Burnett L. & Hamilton, William T.
Item Type: Refine your search to only Report
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Critical combinations of shear and transverse direct stress for an infinitely long flat plate with edges elastically restrained against rotation

Description: An exact solution and a closely concurring approximate energy solution are given for the buckling of an infinitely long flat plate under combined shear and transverse direct stress with edges elastically restrained against rotation. It was found that an appreciable fraction of the critical stress in pure shear may be applied to the plate without any reduction in the transverse compressive stress necessary to produce buckling. An interaction formula in general use was shown to be decidedly conse… more
Date: November 8, 1944
Creator: Batdorf, S. B. & Houbolt, John C.
Item Type: Refine your search to only Report
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Critical Stress of Ring-Stiffened Cylinders in Torsion

Description: "A chart in terms of nondimensional parameters is presented for the theoretical critical stress in torsion of simply supported cylinders stiffened by identical equally spaced rings of zero torsional stiffness. The results are obtained by solving the equation of equilibrium by means of the Galerkin method. Comparison of the theoretical results with experimental results indicates that ring-stiffened cylinders buckle, on the average, at a buckling stress about 15 percent below the theoretical buck… more
Date: November 1949
Creator: Stein, Manuel; Sanders, J. Lyell, Jr. & Crate, Harold
Item Type: Refine your search to only Report
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Derivation of charts for determining the horizontal tail load variation with any elevator motion

Description: From Summary: "The equations relating the wing and tail loads are derived for a unit elevator displacement. These equations are then converted into a nondimensional form and charts are given by which the wing- and tail-load-increment variation may be determined under dynamic conditions for any type of elevator motion and for various degrees of airplane stability. In order to illustrate the use of the charts, several examples are included in which the wing and tail loads are evaluated for a numb… more
Date: November 23, 1942
Creator: Pearson, Henry A.
Item Type: Refine your search to only Report
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The Design of Plywood Webs for Airplane Wing Beams

Description: This report deals with the design of plywood webs for wooden box beams to obtain maximum strength per unit weight. A method of arriving at the most efficient and economical web thickness, and hence the most suitable unit shear stress, is presented and working stresses in shear for various types of webs and species of plywood are given. The questions of diaphragm spacing and required glue area between the webs and flange are also discussed.
Date: November 27, 1929
Creator: Trayer, George W.
Item Type: Refine your search to only Report
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A discussion of certain problems connected with the design of hulls of flying boats and the use of general test data

Description: Report presents the results of a survey of problems encountered in applying general test data to the design of flying-boat hulls. It is shown how basic design features may be readily determined from special plots of test data. A study of the effect of the size of a flying boat on the probable limits to be covered by the general test data is included and recommendations for special tests and new methods of presenting test data for direct use in design are given.
Date: November 1937
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
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