Aerodynamic characteristics of a flying-boat hull having a length-beam ratio of 15 and a warped forebody (open access)

Aerodynamic characteristics of a flying-boat hull having a length-beam ratio of 15 and a warped forebody

From Introduction: "The results of two phases of this investigation, presented in references 1 and 2, have indicated possible ways of reducing hull drag without causing large changes in aerodynamic stability and hydrodynamic performance."
Date: February 11, 1949
Creator: MacLeod, Richard G.
System: The UNT Digital Library
Aerodynamic Characteristics of a Wing With Quarter-Chord Line Swept Back 45 Degrees, Aspect Ratio 4, Taper Ratio 0.6, and NACA 65A006 Airfoil Section: Transonic-Bump Method (open access)

Aerodynamic Characteristics of a Wing With Quarter-Chord Line Swept Back 45 Degrees, Aspect Ratio 4, Taper Ratio 0.6, and NACA 65A006 Airfoil Section: Transonic-Bump Method

Report discussing a particular wing-body combination that is part of a larger investigation to determine the lift, drag, pitching moment, and root bending moments for various configurations. Information about the aerodynamic characteristics at the tail plane is also provided.
Date: February 24, 1949
Creator: Weil, Joseph & Goodson, Kenneth W.
System: The UNT Digital Library
The application of airfoil studies to helicopter rotor design (open access)

The application of airfoil studies to helicopter rotor design

From Summary: "In order to facilitate the application of miscellaneous airfoil data to the problems of the helicopter designer, a discussion of a number of the problems most frequently arising is presented. A reference list of published papers on airfoil section characteristics (or their application) which experience has shown to be useful in connection with these helicopter problems is included."
Date: February 1949
Creator: Gustafson, F. B.
System: The UNT Digital Library
The Buckling of Parallel Simply Supported Tension and Compression Members Connected by Elastic Deflectional Springs (open access)

The Buckling of Parallel Simply Supported Tension and Compression Members Connected by Elastic Deflectional Springs

Note presenting an investigation of the problem of the buckling of parallel simply supported tension and compression members connected by equally stiff and equally spaced elastic deflection springs as an approximation to the problem of the effect of finite stiffness of ribs and tension surface on the buckling load of the compression surface of a wing. Charts relating compressive buckling load, deflectional spring stiffness, and the ratio of the flexural stiffness of the members are given for tension and compression members with various numbers of spans.
Date: February 1949
Creator: Seide, Paul & Eppler, John F.
System: The UNT Digital Library
Calculation of Aerodynamic Forces on a Propeller in Pitch or Yaw (open access)

Calculation of Aerodynamic Forces on a Propeller in Pitch or Yaw

Report presenting an analysis to determine the applicability of existing propeller theory and the theory of oscillating airfoils to the problem of determining the magnitude of the forces on propellers in pitch or yaw. The steady-state method for calculating propeller forces appears to give satisfactory results.
Date: February 15, 1949
Creator: Crigler, John L. & Gilman, Jean, Jr.
System: The UNT Digital Library
Carbon deposition of 19 fuels in an annular turbojet combustor (open access)

Carbon deposition of 19 fuels in an annular turbojet combustor

Report presenting the effects of fuel properties and change in simulated engine operating conditions on carbon deposition in an annular turbojet combustor. The fuel properties examined included specific gravity, volumetric average boiling temperature, hydrocarbon type, and hydrogen-carbon weight ratio. The fuels included hydrocarbons of the paraffinic, olefinic, and aromatic types as well as fuel mixtures.
Date: February 3, 1949
Creator: Wear, Jerrold D. & Jonash, Edmund R.
System: The UNT Digital Library
Compression Shocks in Two-Dimensional Gas Flows (open access)

Compression Shocks in Two-Dimensional Gas Flows

"The following are arguments on the compression shocks in gas flow start with a simplified representation of the results of the study made by Th. Meyer as published in the Forschungsheft 62 of the VDI, supplemented by several amplifications for the application. In the treatment of compression shocks, the equation of energy, the equation of continuity, the momentum equation, the equation of state of the particular gas, as well as the condition Of the second law of thermodynamics that no decrease of entropy is possible in an isolated system, must be taken into consideration" (p. 1).
Date: February 1949
Creator: Busemann, A.
System: The UNT Digital Library
Determination of plate compressive strengths at elevated temperatures (open access)

Determination of plate compressive strengths at elevated temperatures

From Summary: "The results of local-instability tests of H-section plate assemblies and compressive stress-strain tests of extruded 75S-T6 aluminum alloy, obtained to determine flat-plate compressive strengths under stabilized elevated-temperature conditions, are given for temperatures up to 600 degrees Fahrenheit. The results show that methods available for calculating the critical compressive stress at room temperature can also be used at elevated temperatures if the applicable compressive stress-strain curve for the material is given."
Date: February 1949
Creator: Heimerl, George J. & Roberts, William M.
System: The UNT Digital Library
Determination of rate, area, and distribution of impingement of of waterdrops on various airfoils from trajectories obtained on the differential analyzer (open access)

Determination of rate, area, and distribution of impingement of of waterdrops on various airfoils from trajectories obtained on the differential analyzer

From Summary: "The trajectories of waterdrops in air flowing over airfoils are determined for three airfoil-angle-of-attack combinations using the differential analyzer to solve the differential equations of motion of the waterdrops. From these trajectories the rate of water impingement, the area of impingement, and the distribution of impingement are determined as functions of two dimensionless moduli. Comparisons are made of the rate of water impingement on these airfoils and the rate of water impingement on cylinders."
Date: February 16, 1949
Creator: Guibert, A. G.; Janssen, E. & Robbins, W. M.
System: The UNT Digital Library
Determination of rate, area, and distribution of impingement of water drops on various airfoils from trajectories obtained on the differential analyzer (open access)

Determination of rate, area, and distribution of impingement of water drops on various airfoils from trajectories obtained on the differential analyzer

From Summary: "The trajectories of waterdrops in air flowing over airfoils are determined for three airfoil-angle-of-attack combinations using the differential analyzer to solve the differential equations of motion of the waterdrops. From these trajectories the rate of water impingement, the area of impingement, and the distribution of impingement are determined as functions of two dimensionless moduli. Comparisons are made of the rate of water impingement on these airfoils and the rate of water impingement on cylinders."
Date: February 16, 1949
Creator: Guibert, A. G.; Janssen, E. & Robbins, W. M.
System: The UNT Digital Library
Determination of Rate, Area, and Distribution of Impingement of Waterdrops on Various Airfoils From Trajectories Obtained on the Differential Analyzer (open access)

Determination of Rate, Area, and Distribution of Impingement of Waterdrops on Various Airfoils From Trajectories Obtained on the Differential Analyzer

"The trajectories of waterdrops in air flowing over airfoils are determined for three airfoil - angle-of-attack combinations using the differential analyzer to solve the differential equations of motion of the waterdrops. From these trajectories the rate of water impingement, the area of impingement, and the distribution of impingement are determined as functions of two dimensionless moduli. Comparisons are made of the rate of water impingement on these airfoils and the rate of water impingement on cylinders" (p. 1).
Date: February 16, 1949
Creator: Guibert, A. G.; Janssen, E. & Robbins, W. M.
System: The UNT Digital Library
Effects of Partial Admission on Performance of a Gas Turbine (open access)

Effects of Partial Admission on Performance of a Gas Turbine

Report presenting an investigation of the effect of partial admission of the driving fluid on the performance of a representative full-admission, production-type gas turbine. Results regarding losses, full-admission performance, partial-admission performance, partial admission as a means of power control, and a comparison of partial admission with other methods of power control are provided.
Date: February 1949
Creator: Kohl, Robert C.; Herzig, Howard Z. & Whitney, Warren J.
System: The UNT Digital Library
Effects of Several Design Variables on Turbine-Wheel Weight (open access)

Effects of Several Design Variables on Turbine-Wheel Weight

Report presenting an analysis showing the effect of several design variables on turbine-wheel flight. Equations are developed for the calculations of weights of the disk, the rim, and the blades, and use the following variables: the blading aspect ratio and solidity, the ratio of the centrifugal stress at the blade roots to that in the disk, and the ratio of wheel diameter at the blade root to wheel diameter at the blade tip.
Date: February 1949
Creator: LaValle, Vincent L. & Huppert, Merle C.
System: The UNT Digital Library
Elastic and plastic buckling of simply supported metalite type sandwich plates in compression (open access)

Elastic and plastic buckling of simply supported metalite type sandwich plates in compression

Report presenting a solution for the problem of the compressive buckling of simply supported, flat, rectangular, Metalite type sandwich plates stressed either in the elastic or plastic range. Charts for the analysis of long sandwich plates are provided for plates with face materials of 24S-T3 aluminum alloy, 75S-T6 Alclad aluminum alloy, and stainless steel.
Date: February 1949
Creator: Seide, Paul & Stowell, Elbridge Z.
System: The UNT Digital Library
Equilibrium Operating Performance of Axial-Flow Turbojet Engines by Means of Idealized Analysis (open access)

Equilibrium Operating Performance of Axial-Flow Turbojet Engines by Means of Idealized Analysis

"A method of predicting equilibrium operating performance of turbojet engines has been developed, with the assumption of simple model processes for the components. Results of the analysis are plotted in terms of dimensionless parameters comprising critical engine dimensions and over-all operating variables. This investigation was made of an engine in which the ratio of axial inlet-air velocity to compressor-tip velocity is constant, which approximates turbojet engines with axial-flow compressors" (p. 673).
Date: February 25, 1949
Creator: Sanders, John C. & Chapin, Edward C.
System: The UNT Digital Library
Estimation of Lift and Drag of Airfoils at Near Sonic Speeds and in the Presence of Detached Shock Waves (open access)

Estimation of Lift and Drag of Airfoils at Near Sonic Speeds and in the Presence of Detached Shock Waves

Report presenting a semiempirical method of estimating the forces on airfoil at near sonic speeds and in the presence of detached shock waves. The calculated values were found to be in good agreement with wind-tunnel testing of the forces on sharp-nose airfoils and two-dimensional wings.
Date: February 23, 1949
Creator: Mayer, John P.
System: The UNT Digital Library
Experimental pressure distribution on a asymmetrical nonconical body at Mach number 1.90 (open access)

Experimental pressure distribution on a asymmetrical nonconical body at Mach number 1.90

Report presenting an investigation of the pressure distribution on an asymmetrical nonconical body at a Mach number of 1.90 over a wide range of angles of attack and yaw. Pressure distributions occurred at anticipated trends. Results regarding the pressure coefficients, Schileren photographs, boundary layers, and pressure distributions are provided.
Date: February 24, 1949
Creator: Wyatt, DeMarquis D.
System: The UNT Digital Library
Flight Investigation of Flutter Models With 1/10-Scale Douglas D-558-2 Wing Panels (open access)

Flight Investigation of Flutter Models With 1/10-Scale Douglas D-558-2 Wing Panels

Report presenting testing of three rocket-powered models with Douglas D-558-2 wings as horizontal fins with scaled structural parameters to determine whether the possibility of wing flutter due to torsion and bending exists in full-scale airplanes at transonic speeds. No wing flutter was present in the models tested, but pitching oscillation developed as it passed into the transonic range.
Date: February 16, 1949
Creator: Teitelbaum, Jerome M.
System: The UNT Digital Library
Investigation of a thin straight wing of aspect ratio 4 by the NACA wing-flow method: Lift and pitching-moment characteristics of the wing alone (open access)

Investigation of a thin straight wing of aspect ratio 4 by the NACA wing-flow method: Lift and pitching-moment characteristics of the wing alone

This report presents measurements of the lift and pitching-moment characteristics of a straight wing of aspect ratio 4, taper ratio 0.5, having a symmetrical double-wedge airfoil section with a maximum thickness of 4.4-percent chord. The tests were conducted in the Mach number range 0.51 to 1.20, Reynolds numbers 380,000 to 660,000, by the NACA wing-flow method. The results are compared with theory and with wind-tunnel tests of a similar model. It is indicated that in the Mach number range 0.82 to 1.00 the model surface, profile, and test Reynolds number all would be very important considerations in any attempt to study or predict full-scale characteristics from small-model tests.
Date: February 14, 1949
Creator: Rathert, George A., Jr.; Hanson, Carl M. & Rolls, L. Stewart
System: The UNT Digital Library
Investigation of Icing Characteristics of Typical Light Airplane Engine Induction Systems (open access)

Investigation of Icing Characteristics of Typical Light Airplane Engine Induction Systems

"The icing characteristics of two typical light-airplane engine induction systems were investigated using the carburetors and manifolds of engines in the horsepower ranges from 65 to 85 and 165 to 185. The smaller system consisted of a float-type carburetor with an unheated manifold and the larger system consisted of a single-barrel pressure-type carburetor with an oil-jacketed manifold. Carburetor-air temperature and humidity limits of visible and serious Icing were determined for various engine power conditions" (p. 1).
Date: February 1949
Creator: Coles, Willard D.
System: The UNT Digital Library
Investigation of the Effect of Tip Tanks on the Wing Loading of a Republic F-84 Airplane in the Ames 40- by 80-foot Wind Tunnel (open access)

Investigation of the Effect of Tip Tanks on the Wing Loading of a Republic F-84 Airplane in the Ames 40- by 80-foot Wind Tunnel

Wind-tunnel tests at low Mach number of a Republic F-84C airplane were conducted to determine by pressure-distribution measurements the air loads on wing-tip tanks and the change in wing load distribution due to the presence of tip tanks. Measurements of the aeroelastic twist of the wing were also obtained. Results are presented in the form of loading coefficient, center-of- pressure location, pitching-moment coefficient, aerodynamic-center location, and aeroelastic twist. The investigation revealed that the redistributions in loading brought about by either the tip tanks or elastic deformation of the wing were relatively small when compared with the chnnges in loading normally associated with the deflection of an aileron.
Date: February 2, 1949
Creator: Hunton, Lynn W.; Dew, Joseph K. & Salisbury, Ralph D.
System: The UNT Digital Library
Laminar mixing of a compressible fluid (open access)

Laminar mixing of a compressible fluid

From Summary: "A theoretical investigation of the velocity profiles for laminar mixing of a high-velocity stream with a region of fluid at rest has been made assuming that the Prandtl number is unity. A method which involves only quadratures is presented for calculating the velocity profile in the mixing layer for an arbitrary value of the free-stream Mach number. Detailed velocity profiles have been calculated for free-stream Mach numbers of 0, 1, 2, 3, and 5."
Date: February 1949
Creator: Chapman, Dean R.
System: The UNT Digital Library
The Longitudinal Stability of Elastic Swept Wings at Supersonic Speed (open access)

The Longitudinal Stability of Elastic Swept Wings at Supersonic Speed

Report presenting calculations of the longitudinal stability characteristics of elastic swept wings of high aspect ratio experiencing bending and torsional deformations by applying the linearized lifting-surface theory. Results of numerical calculations for a wing of aspect ratio 3.2 and 60 degrees of sweepback at Mach number 1.414 are provided. A discussion of the supersonic lifting-surface theory, comparison of aeroelastic effects at supersonic speed with incompressible flow solutions, and strip theory are also provided.
Date: February 1949
Creator: Frick, C. W. & Chubb, R. S.
System: The UNT Digital Library
Method for Evaluating From Shadow or Schlieren Photographs the Pressure Drag in Two-Dimensional or Axially Symmetrical Flow Phenomena With Detached Shock (open access)

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

"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
System: The UNT Digital Library