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Charts for the Computation of Equilibrium Composition of Chemical Reactions in the Carbon-Hydrogen-Nitrogen System at Temperatures from 2000 to 5000 Degrees K

Description: Charts are provided for the estimation and progressive adjustment of two independent variables on which the calculations are based. Additional charts are provided for the graphical calculation of the composition.
Date: July 1948
Creator: Huff, Vearl N. & Calvert, Clyde S.
Partner: UNT Libraries Government Documents Department

The Method of Characteristics for the Determination of Supersonic Flow Over Bodies of Revolution at Small Angles of Attack

Description: Note presenting the use of the method of characteristics for the determination of the supersonic-flow properties around bodies of revolution at a small angle of attack. The system developed considers the effect of the variation of entropy due to the curved shock and determines a flow that exactly satisfies the boundary conditions in the limits of the simplifications assumed.
Date: February 1949
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department

Preliminary Wind-Tunnel Investigation at Low Speed of Stability and Control Characteristics of Swept Back Wings

Description: Note presenting tests conducted on untapered constant-span wings of 0, 30, 45, and 60 degrees sweepback. The purpose of the tests was to investigate the effect of sweepback on stability and control characteristics. The data showed large changes in longitudinal stability at moderate lift coefficients for the 45 and 60 degree sweptback wings.
Date: April 1946
Creator: Letko, William & Goodman, Alex
Partner: UNT Libraries Government Documents Department

Bending of Rectangular Plates With Large Deflections

Description: Note presenting Von Kármán's equations for thin plates with large deflections are solved for the special cases of rectangular plates with ratios of length to width of 1.5 and 2 and loaded by uniform normal pressure. The boundary conditions are such to approximate panels with riveted edges under normal pressure greater than that of the surrounding panels.
Date: April 1948
Creator: Wang, Chi-Teh
Partner: UNT Libraries Government Documents Department

Nondestructive Measurement of Residual and Enforced Stresses by Means of X-Ray Diffraction 2: Some Applications to Aircraft Problems

Description: Note presenting tests on the use of x-ray diffraction methods for determining surface stress distributions in notched tensile bars and in the vicinity of a welded joint in aircraft steel tubing. Data on the effects of stress and degree of notching on the principal stresses and stress-concentration factors for flat notched tensile-test specimens were obtained.
Date: November 1945
Creator: Sachs, George; Smith, Charles S.; Lubahn, Jack D.; Davis, Gordon E. & Ebert, Lynn J.
Partner: UNT Libraries Government Documents Department

An Exploration of the Longitudinal Tensile and Compressive Properties Throughout an Extruded Shape of 24S-T Aluminum Alloy

Description: Note presenting an investigation of tensile and compressive properties of specimens cut from an extruded shape of 24S-T aluminum alloy. The tensile strengths, tensile yield strengths, elongations, and compressive yield strengths of both the uncrystallized and recrystallized portions were determined. The strength of a cross section of an extruded shape is the weighted average of the strengths of the unrecrystallized and the recrystallized areas.
Date: December 1942
Creator: Paul, D. A.
Partner: UNT Libraries Government Documents Department

Measurements of Recovery Factors and Coefficients of Heat Transfer in a Tube for Subsonic Flow of Air

Description: Note presenting measurements of heat flow to air at subsonic velocities and substantially constant Reynolds number, which show that the heat-transfer coefficient is independent of the difference between the temperature of the heated wall and the adiabatic wall temperature. Recovery factors are measured at the pipe wall for adiabatic flow.
Date: June 1945
Creator: McAdams, William H.; Nicolai, Lloyd A. & Keenan, Joseph H.
Partner: UNT Libraries Government Documents Department

Flight Measurements of the Flying Qualities of Five Light Airplanes

Description: Note presenting results of an investigation made to determine measurements of stability, controllability, and stalling characteristics of five light airplanes. Results regarding the longitudinal stability and control characteristics, lateral stability and control characteristics, stalling characteristics, spinning characteristics, and effect of slots on flying qualities are provided.
Date: May 1948
Creator: Hunter, Paul A.
Partner: UNT Libraries Government Documents Department

Nondestructive Measurement of Residual and Enforced Stresses by Means of X-Ray Diffraction 1: Correlated Abstract of the Literature

Description: Note presenting a study of the stress measurements by means of the x-ray diffraction method, which have found considerable application in solving both commercial and laboratory problems. Two problems related to x-ray diffraction are studied and a literature review is conducted.
Date: September 1945
Creator: Sachs, George; Smith, Charles S.; Lubahn, Jack D.; Davis, Gordon E. & Ebert, Lynn J.
Partner: UNT Libraries Government Documents Department

Oxidation Characteristics of Molybdenum Disulfide and Effect of Such Oxidation on Its Role as a Solid-Film Lubricant

Description: Note presenting an investigation conducted to determine the oxidation characteristics of molybdenum disulfide and to determine the effect of such oxidation on its role as a solid-film lubricant. A coating of molybdenum disulfide serving as a high-temperature solid-film lubricant maintained low coefficient-of-friction values during its oxidation as long as an effective subfilm of the molybdenum disulfide remained.
Date: May 1949
Creator: Godfrey, Douglas & Nelson, Erva C.
Partner: UNT Libraries Government Documents Department

Nondestructive Test Methods for Spot Welds in Aluminum Alloys

Description: Note presenting the results of a study and research investigation of nondestructive test methods for spot welds in aluminum-alloy sheets. The purpose of the research was to investigate proposed nondestructive test methods for spot welds in aluminum alloys, to determine the feasibility of the tests, and to recommend the research methods found suitable for development and reduction to practical application.
Date: November 1944
Creator: McMaster, R. C.; Manildi, J. F. & Woolsey, C. C.
Partner: UNT Libraries Government Documents Department

Method for Evaluating From Shadow or Schlieren Photographs the Pressure Drag in Two-Dimensional or Axially Symmetrical Flow Phenomena With Detached Shock

Description: "A method has been developed for evaluating from shadow or schileren photographs the pressure drag of axially symmetrical bodies at zero angle of attack or of two-dimensional bodies producing detached shock. The method consists in the determination of the flow properties along a characteristic line and the application of the momentum theorem to a stream tube around the body. The method can be applied to the determination of external drag of supersonic inlets with subsonic flow at the entrance of the inlet" (p. 1).
Date: February 1949
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department

Analysis of Square Shear Web Above Buckling Load

Description: "A solution of Von Karman's fundamental equations for plates with large deflections is presented for the case of a shear web divided into square panels by reinforcing struts. Numerical solutions are given for struts of infinite rigidity and for struts the weight of which is one-fourth the weight of the sheet. The results are compared with Wagner's diagonal tension theory as extended by Kuhn and by Langhaar. It is found that the diagonal tension theory as developed by Kuhn agrees best with the present paper in the practical range when r=1/4. Kuhn's theory is in especially good agreement for the force in the strut when r=1/4" (p. 1).
Date: July 1944
Creator: Levy, Samuel; Fienup, Kenneth L. & Woolley, Ruth M.
Partner: UNT Libraries Government Documents Department

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

Description: Note presenting an investigation of the laminar boundary layer and the position of the transition point on a heated flat plate. The Reynolds number of transition was found to decrease as the temperature of the plate is increased. Results regarding the effect of surface temperature, effect of roughness elements, mean-velocity profile near a heated wall, instability of inflection-point profiles, and laminar separation and transition are provided.
Date: April 1947
Creator: Liepmann, Hans W. & Fila, Gertrude H.
Partner: UNT Libraries Government Documents Department

High-Speed Investigation of Skin Wrinkles on Two NACA Airfoils

Description: Note presenting an investigation of the effects on the aerodynamic characteristics of skin wrinkles on the forward part of the upper surface of two NACA airfoils. The results showed that no appreciable change in normal-force or pitching-moment characteristics over the range of Mach numbers tested was noted. The drag was greater on the wrinkled sections than the smooth sections, however.
Date: August 1946
Creator: Robinson, Harold L.
Partner: UNT Libraries Government Documents Department

An Investigation of Fretting Corrosion Under Several Conditions of Oxidation

Description: Note presenting a study to gain information as to the fundamental mechanism of fretting corrosion. The specific questions to be answered were whether chemical action played an important role in fretting of metal surfaces and whether any such action would improve the corrosion resistance of the metal investigated. The results indicated that the chemical action is of primary importance in fretting-corrosion effects and oxide formation does not give any protection to the metals but rather increases the rate of wear.
Date: June 1948
Creator: Sakmann, B. W. & Rightmire, B. G.
Partner: UNT Libraries Government Documents Department

Flight Investigation at High Speeds of the Drag of Three Airfoils and a Circular Cylinder Representing Full-Scale Propeller Shanks

Description: Note presenting tests at high speeds to determine the drag of models, simulating propeller shanks, in the form of a circular cylinder and three airfoils with the rear 25 percent chord cut off. The results indicated that the drag of the airfoils was lower than that of the cylinder over the Mach number range investigated.
Date: September 1946
Creator: Barlow, William H.
Partner: UNT Libraries Government Documents Department

Investigation of Flow Coefficient of Circular, Square, and Elliptical Orifices at High Pressure Ratios

Description: Note presenting an experimental investigation conducted to determine the orifice coefficient of a jet directed perpendicularly to an air stream as a function of pressure ratio and jet Reynolds number for circular, square, and elliptical orifices. The effect of air-stream velocity on the jet flow was also determined for three tunnel-air velocities. Results regarding jets discharging into still air and effect of tunnel-air velocity on jet flow.
Date: September 1949
Creator: Callaghan, Edmund E. & Bowden, Dean T.
Partner: UNT Libraries Government Documents Department

Flight Measurements of the Lateral Control Characteristics of Narrow-Chord Ailerons on the Trailing Edge of a Full-Span Slotted Flap

Description: Note presenting results of flight tests made to determine the effect of flap deflection on the lateral control characteristics of a modified Brewster F2A-2 airplane equipped with partial-span narrow-chord ailerons on the trailing edge of a full-span NACA slotted flap. The results indicated that the effectiveness of the ailerons was greatly reduced at flap deflections greater than about 20 degrees.
Date: February 1947
Creator: Sawyer, Richard H.
Partner: UNT Libraries Government Documents Department

Flow Tests of an NACA-Designed Supercharger Inlet Elbow and the Effects of Various Components on the Flow Characteristics at the Elbow Outlet

Description: Note presenting an investigation on a supercharger inlet elbow designed to have a uniform velocity distribution at the outlet with a minimum pressure loss through the bend. The effects of a vane, an impeller-shaft housing, and the combination of the two on the outlet-velocity distribution and total pressure drop through the elbow were determined.
Date: October 1946
Creator: Guentert, D. C.; Todd, D. J. & Simmons, W. P., Jr.
Partner: UNT Libraries Government Documents Department

Investigation of Suction-Slot Shapes for Controlling a Turbulent Boundary Layer

Description: Note presenting tests of three types of boundary-layer-control suction slots in a two-dimensional diffuser to investigate design criterions and to evaluate the practical minimum total-pressure losses. Testing occurred at a velocity of about 100 feet per second with a boundary layer with a displacement thickness of 0.85 inch and a shape parameter of about 1.8.
Date: June 1947
Creator: Pierpont, P. Kenneth
Partner: UNT Libraries Government Documents Department

A Method for Numerically Calculating the Area and Distribution of Water Impingement on the Leading Edge of an Airfoil in a Cloud

Description: Note presenting a method for determining, by step-by-step integration, the trajectories of water drops around any body in two-dimensional flow for which the streamline velocity components are known or can be computed. The equations are presented in general form and then, to illustrate the procedure, water-drop trajectories are calculated about a 12-percent-thick symmetrical Joukowski profile chosen to simulate an NACA 0012 section. The method provides a means for the relatively rapid calculation of the trajectory of a single drop without the utilization of a differential analyzer.
Date: August 1947
Creator: Bergrun, Norman R.
Partner: UNT Libraries Government Documents Department