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The reversibility theorem for thin airfoils in subsonic and supersonic flow

Description: A method introduced by Munk is extended to prove that the light-curve slope of thin wings in either subsonic flow or supersonic flow is the same when the direction of flight of the wing is reversed. It is also shown that the wing reversal does not change the thickness drag, damping-in-roll parameter or the damping-in-pitch parameter.
Date: June 26, 1949
Creator: Brown, Clinton E.
Partner: UNT Libraries Government Documents Department
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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.
Partner: UNT Libraries Government Documents Department
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Influence of chemical composition on rupture properties at 1200 degrees F of forged chromium-cobalt-nickel-iron base alloys in solution-treated and aged condition

Description: From Summary: "The influence of systematic variations of chemical composition on rupture properties at 1200 degrees F. was determined for 62 modifications of a basic alloy containing 20 percent chromium, 20 percent nickel, 20 percent cobalt, 3 percent molybdenum, 2 percent tungsten, 1 percent columbium, 0.15 percent carbon, 1.7 percent manganese, 0.5 percent silicon, 0.12 percent nitrogen and the balance iron. These modifications included individual variations of each of 10 elements present and… more
Date: October 26, 1949
Creator: Reynolds, E. E.; Freeman, J. W. & White, A. E.
Partner: UNT Libraries Government Documents Department
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Investigation of wear and friction properties under sliding conditions of some materials suitable for cages of rolling-contact bearings

Description: "An investigation of wear and friction properties of a number of materials sliding against SAE 52100 steel was conducted. These materials included brass, bronze, beryllium copper, monel, nichrome v, 24S-T aluminum, nodular iron, and gray cast iron. The metals investigated may be useful as possible cage (separator or retainer) materials for rolling-contact bearings of high-speed turbine engines. The ability of materials to form surface films that prevent welding is a most important factor in bot… more
Date: March 26, 1951
Creator: Johnson, Robert L.; Swikert, Max A. & Bisson, Edmond E.
Partner: UNT Libraries Government Documents Department
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A summary of lateral-stability derivatives calculated for wing plan forms in supersonic flow

Description: "A compilation of theoretical values of the lateral-stability derivatives for wings at supersonic speeds is presented in the form of design charts. The wing plan forms for which this compilation has been prepared include a rectangular, two trapezoidal, two triangular, a fully-tapered swept-back, a sweptback hexagonal, an unswept hexagonal, and a notched triangular plan form. A full set of results, that is, values for all nine of the lateral-stability derivatives for wings, was available for the… more
Date: June 26, 1951
Creator: Jones, Arthur L. & Alksne, Alberta
Partner: UNT Libraries Government Documents Department
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Convection of a pattern of vorticity through a shock wave

Description: An arbitrary weak spatial distribution of vorticity can be represented in terms of plane sinusoidal shear waves of all orientations and wave lengths (Fourier integral). The analysis treats the passage of a single representative weak shear wave through a plane shock and shows refraction and modification of the shear wave with simultaneous generation of an acoustically intense sound wave. Applications to turbulence and to noise in supersonic wind tunnels are indicated.
Date: September 26, 1952
Creator: Ribner, H. S.
Partner: UNT Libraries Government Documents Department
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Comparative Flight and Full-Scale Wind-Tunnel Measurements of the Maximum Lift of an Airplane

Description: "Determinations of the power-off maximum lift of a Fairchild 22 airplane were made in the NACA full-scale wind tunnel and in flight. The results from the two types of test were in satisfactory agreement. It was found that, when the airplane was rotated positively in pitch through the angle of stall at rates of the order of 0.1 degree per second, the maximum lift coefficient was considerably higher than that obtained in the standard tests, in which the forces are measured with the angles of atta… more
Date: October 26, 1937
Creator: Silverstein, Abe; Katzoff, S. & Hootman, James A.
Partner: UNT Libraries Government Documents Department
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The Transition Phase in the Take-Off of an Airplane

Description: Report presents the results of an investigation to determine the character and importance of the transition phase between the ground run and steady climb in the take-off of an airplane and the effects of various factors on this phase and on the air-borne part of the take-off as a whole. The information was obtained from a series of step-by-step integrations, which defined the motion of the airplane during the transition and which were based on data derived from actual take-off tests of a Vervil… more
Date: October 26, 1937
Creator: Wetmore, J. W.
Partner: UNT Libraries Government Documents Department
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Determination of boundary-layer transition on three symmetrical airfoils in the NACA full-scale wind tunnel

Description: For the purpose of studying the transition from laminar to turbulent flow, boundary-layer measurements were made in the NACA full-scale wind tunnel on three symmetrical airfoils of NACA 0009, 0012, and 0018 sections. The effects of variations in lift coefficient, Reynolds number, and airfoil thickness on transition were investigated. Air speed in the boundary layer was measured by total-head tubes and by hot wires; a comparison of transition as indicated by the two techniques was obtained. The … more
Date: May 26, 1938
Creator: Silverstein, Abe & Becker, John V.
Partner: UNT Libraries Government Documents Department
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Effects of air-fuel spray and flame formation in a compression-ignition engine

Description: "High-speed motion pictures were taken at the rate of 2,500 frames per second of the fuel spray and flame formation in the combustion chamber of the NACA combustion apparatus. The compression ratio was 13.2 and the speed 1,500 revolutions per minute. An optical indicator was used to record the time-pressure relationship in the combustion chamber. The air-fuel ratio was varied from 10.4 to 365. The results showed that as the air-fuel ratio was increased definite stratification of the charge occu… more
Date: August 26, 1935
Creator: Rothrock, A. M. & Waldron, C. D.
Partner: UNT Libraries Government Documents Department
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Tests of Nacelle-Propeller Combinations in Various Positions with Reference to Wings 5: Clark Y Biplane Cellule - NACA Cowled Nacelle - Tractor Propeller

Description: "This report is the fifth of a series giving the results obtained from wind tunnel tests on the interference drag and propulsive efficiency of nacelle-propeller-wing combinations. This report gives results of tests of an NACA cowled air-cooled engine nacelle with tractor propeller located in 12 positions with reference to a Clark Y biplane cellule" (p. 603).
Date: January 26, 1934
Creator: Valentine, E. Floyd
Partner: UNT Libraries Government Documents Department
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The effect of baffles on the temperature distribution and heat-transfer coefficients of finned cylinders

Description: This report presents the results of an investigation to determine the effect of baffles on the temperature distribution and the heat-transfer coefficient of finned cylinders. The tests were conducted in a 30-inch wind tunnel on electrically heated cylinders with fins of 0.25 and 0.31 inch pitch. The results of these tests showed that the use of integral baffles gave a reduction of 31.9 percent in the rear wall temperatures and an increase of 54.2 percent in the heat transfer coefficient as comp… more
Date: September 26, 1934
Creator: Schey, Oscar W. & Rollin, Vern G.
Partner: UNT Libraries Government Documents Department
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The NACA Apparatus for Studying the Formation and Combustion of Fuel Sprays and the Results From Preliminary Tests

Description: "This report describes the apparatus as designed and constructed at the Langley Memorial Aeronautical Laboratory, for studying the formation and combustion of fuel sprays under conditions closely simulating those occurring in a high-speed compression-ignition engine. The apparatus consists of a single-cylinder modified test engine, a fuel-injection system so designed that a single charge of fuel can be injected into the combustion chamber of the engine, an electric driving motor, and a high-spe… more
Date: August 26, 1931
Creator: Rothrock, A. M.
Partner: UNT Libraries Government Documents Department
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The drag of two streamline bodies as affected by protuberances and appendages

Description: This report presents the results of wind tunnel tests of two airship models conducted to determine the drag coefficients at zero pitch, and the effect of fins and cars and of flat and streamlined protuberances located at various positions along the hull. During the investigation the stern of one model was rounded off to produce a blunter shape. The extreme range of the Reynolds number based on the over-all length of the models was from 1,300,000 to 33,000,000. At large values of the Reynolds nu… more
Date: September 26, 1932
Creator: Abbott, Ira H.
Partner: UNT Libraries Government Documents Department
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Heat transfer from finned metal cylinders in an air stream

Description: This report presents the results of tests made to supply design information for the construction of metal fins for the cooling of heated cylindrical surfaces by an air stream. A method is given for determining fin dimensions for a maximum heat transfer with the expenditure of a given amount of material for a variety of conditions of air flow and metals.
Date: April 26, 1934
Creator: Biermann, Arnold E. & Pinkel, Benjamin
Partner: UNT Libraries Government Documents Department
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Supersonic Flow Around Circular Cones at Angles of Attack

Description: The properties of conical flow without axial symmetry are analyzed. The flow around cones of circular cross section at small angles of attack is determined by correctly considering the effect of the entropy gradients in the flow.
Date: September 26, 1950
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department
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Effect of Screens in Wide-Angle Diffusers

Description: "An experimental investigation at low airspeeds was made of the filling effect observed when a screen or similar resistance is placed across a diffuser. The filling effect is found to be real in that screens can prevent separation or restore separated flow in diffusers even of extreme divergence and to depend principally on screen location and pressure-drop coefficient of the screen. Results are given for three different diffusers of circular cross section with a variety of screen arrangements.… more
Date: June 26, 1947
Creator: Schubauer, G. B. & Spangenberg, W. G.
Partner: UNT Libraries Government Documents Department
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Investigation of Air Flow in Open-Throat Wind Tunnels

Description: "Tests were conducted on the 6-inch wind tunnel of the National Advisory Committee for Aeronautics to form a part of a research on open-throat wind tunnels. The primary object of this part of the research was to study a type of air pulsation which has been encountered in open-throat tunnels, and to find the most satisfactory means of eliminating such pulsations. In order to do this it was necessary to study the effects of different variable on all of the important characteristics of the tunnel"… more
Date: September 26, 1928
Creator: Jacobs, Eastman N.
Partner: UNT Libraries Government Documents Department
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Experimental and analytical determination of the motion of hydraulically operated valve stems in oil engine injection systems

Description: This research on the pressure variations in the injection system of the N.A.C.A. Spray Photography Equipment and on the effects of these variations on the motion of the timing valve stem was undertaken in connection with the study of fuel injection systems for high-speed oil engines. The methods of analysis of the pressure variations and the general equation for the motion of the spring-loaded stem for the timing valve are applicable to a spring-loaded automatic injection valve, and in general … more
Date: December 26, 1928
Creator: Gelalles, A. G. & Rothrock, A. M.
Partner: UNT Libraries Government Documents Department
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Survey of hydrogen combustion properties

Description: This literature digest of hydrogen-air combustion fundamentals presents data on flame temperature, burning velocity, quenching distance, flammability limits, ignition energy, flame stability, detonation, spontaneous ignition, and explosion limits. The data are assessed, recommended values are given, and relations among various combustion properties are discussed. New material presented includes: theoretical treatment of variation in spontaneous ignition lag with temperature, pressure, and compo… more
Date: April 26, 1957
Creator: Drell, Isadore L. & Belles, Frank E.
Partner: UNT Libraries Government Documents Department
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General method and thermodynamic tables for computation of equilibrium composition and temperature of chemical reactions

Description: From Summary: "A rapidly convergent successive approximation process is described that simultaneously determines both composition and temperature resulting from a chemical reaction. This method is suitable for use with any set of reactants over the complete range of mixture ratios as long as the products of reaction are ideal gases. An approximate treatment of limited amounts of liquids and solids is also included. This method is particularly suited to problems having a large number of products… more
Date: January 26, 1950
Creator: Huff, Vearl N.; Gordon, Sanford & Morrell, Virginia E.
Partner: UNT Libraries Government Documents Department
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Some effects of frequency on the contribution of a vertical tail to the free aerodynamic damping of a model oscillating in yaw

Description: The damping in yaw and the directional stability of a model freely oscillating in yaw were measured tail-off and tail-on and compared with the values obtained by theoretical consideration of the unsteady lift associated with an oscillating vertical tail. A range of low frequencies comparable to those of the lateral motions of airplanes was covered. The analysis includes the effects of vertical-tail aspect ratio and the two-dimensional effects of compressibility.
Date: November 26, 1951
Creator: Bird, John D.; Fisher, Lewis R. & Hubbard, Sadie M.
Partner: UNT Libraries Government Documents Department
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