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Analysis of cooling limitations and effect of engine-cooling improvements on level-flight cruising performance of four-engine heavy bomber

Description: From Introduction: "The difficulties experienced in cooling the exhaust-valve seats of the rear-row cylinders have been overcome to a considerable extent by improving the mixture distribution through application of the injection impeller (reference 1) and by augmenting the flow of cooling air to the critical baffles (reference 2). Flight tests of this airplane (reference 3) indicated that the temperatures of exhaust-valve seats on rear-row cylinders were markedly lowered by these modifications … more
Date: March 14, 1946
Creator: Marble, Frank E.; Miller, Marlon A. & Bell, E. Barton
Partner: UNT Libraries Government Documents Department
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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
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Analysis of spark-ignition engine knock as seen in photographs taken at 200,000 frames per second

Description: Report discussing a motion picture of the development of knock in a spark-ignition engine, which consists of 20 photographs taken at intervals of 5 microseconds, or at a rate of 200,000 photographs per second, with an equivalent wide-open exposure time of 6.4 microseconds for each photograph.
Date: 1946~
Creator: Miller, Cearcy D.; Olsen, H. Lowell; Logan, Walter O., Jr. & Osterstrom, Gordon E.
Partner: UNT Libraries Government Documents Department
open access

Application of the Analogy Between Water Flow With a Free Surface and Two-Dimensional Compressible Gas Flow

Description: "The theory of the hydraulic analogy -- that is, the analogy between water flow with a free surface and two-dimensional compressible gas flow -- and the limitations and conditions of the analogy are discussed. A test was run using the hydraulic analogy as applied to the flow about circular cylinders of various diameters at subsonic velocities extending into the supercritical range. The apparatus and techniques used in this application are described and criticized" (p. 311).
Date: August 21, 1946
Creator: Orlin, W. James; Lindner, Norman J. & Bitterly, Jack G.
Partner: UNT Libraries Government Documents Department
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Application of the Method of Characteristics to Supersonic Rotational Flow

Description: "A system for calculating the physical properties of supersonic rotational flow with axial symmetry and supersonic rotational flow in a two-dimensional field was determined by use of the characteristics method. The system was applied to the study of external and internal flow for supersonic inlets with axial symmetry. For a circular conical inlet the shock that occurred at the lip of the inlet became stronger as it approached the axis of the inlet and became a normal shock at the axis" (p. 111). more
Date: April 29, 1946
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department
open access

Compressibility Effects on the Longitudinal Stability and Control of a Pursuit-Type Airplane as Measured in Flight

Description: Measurements of the longitudinal stability and control of a pursuit-type airplane were made in flight up to a Mach number of 0.78. The data are presented in the form of curves showing the variation, with center-of-gravity position, dynamic pressure, and Mach number, of the stick-fixed and stick-free stability, control, and balance of the airplane.
Date: 1946
Creator: Turner, William N.; Steffen, Paul J. & Clousing, Lawrence A.
Partner: UNT Libraries Government Documents Department
open access

Consideration of Dynamic Loads on the Vertical Tail by the Theory of Flat Yawing Maneuvers

Description: "Dynamic yawing effects on vertical-tail loads are considered by a theory of flat yawing maneuvers. A comparison is shown between computed loads and the loads measured in flight on a fighter airplane. The dynamic effects were investigated on a large flying boat for both an abrupt rudder deflection and sinusoidal rudder deflection" (p. 91).
Date: March 15, 1946
Creator: Boshar, John & Davis, Philip
Partner: UNT Libraries Government Documents Department
open access

Cylinder-Temperature Correlation of a Single-Cylinder Liquid-Cooled Engine

Description: "An analysis based on nonboiling forced-convection heat-transfer theory is made of the cooling processes in liquid-cooled engine cylinders. Semiempirical equations that relate the average head and barrel temperatures with the primary engine and coolant parameters are derived. A correlation method based on these equations is applied to data obtained from previously reported investigations, which were conducted over large ranges of engine and coolant conditions with two liquid-cooled cylinders us… more
Date: October 1, 1946
Creator: Pinkel, Benjamin; Manganiello, Eugene J. & Bernardo, Everett
Partner: UNT Libraries Government Documents Department
open access

Effect of Compressibility at High Subsonic Velocities on the Lifting Force Acting on an Elliptic Cylinder

Description: An extended form of the Ackeret iteration method, applicable to arbitrary profiles, is utilized to calculate the compressible flow at high subsonic velocities past an elliptic cylinder. The angle of attack to the direction of the undisturbed stream is small and the circulation is fixed by the Kutta condition at the trailing end of the major axis. The expression for the lifting force on the elliptic cylinder is derived and shows a first-step improvement of the Prandtl-Glauert rule. It is further… more
Date: May 16, 1946
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
open access

The effect of wall interference upon the aerodynamic characteristics of an airfoil spanning a closed-throat circular wind tunnel

Description: "The results of a theoretical and experimental investigation of wall interference for an airfoil spanning a closed-throat circular wind tunnel are presented. Analytical equations are derived which relate the characteristics of an airfoil in the tunnel at subsonic speeds with the characteristics in free air. The analysis takes into consideration the effect of fluid compressibility and is based upon the assumption that the chord of the airfoil is small as compared with the diameter of the tunnel"… more
Date: 1946
Creator: Vincenti, Walter G. & Graham, Donald J.
Partner: UNT Libraries Government Documents Department
open access

The Effects of Aerodynamic Heating and Heat Transfer on the Surface Temperature of a Body of Revolution in Steady Supersonic Flight

Description: "An approximate method for determining the convective cooling requirement in the laminar boundary-layer region of a body of revolution in high-speed flight was developed and applied to an example body. The cooling requirement for the example body was determined as a function of Mach number, altitude, size, and a surface-temperature parameter. The maximum value of Mach number considered was 3.0 and the altitudes considered were those within the lower constant-temperature region of the atmosphere… more
Date: October 14, 1946
Creator: Scherrer, Richard
Partner: UNT Libraries Government Documents Department
open access

Experimental and theoretical studies of surging in continuous-flow compressors

Description: Experiments have been conducted to determine the conditions that cause surging in compressors and to determine the effect of various installations and operating conditions on the character of the velocity and pressure variations occurring during surging. These investigations were made on three compressor units and the variation of static, total, and velocity pressure with time was recorded. In addition to the experimental studies, a simplified analysis was made to determine how instability of f… more
Date: 1946
Creator: Bullock, Robert O.; Wilcox, Ward W. & Moses, Jason J.
Partner: UNT Libraries Government Documents Department
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Flight Investigation at High Speeds of the Drag of Three Airfoils and a Circular Cylinder Representing Full-Scale Propeller Shanks

Description: "Tests have been made at high speeds to determine the drag of models, simulating propeller shanks, in the form of a circular cylinder and three airfoils, the NACA 16-025, the NACA 16-040, and the NACA 16-040 with the rear 25 percent chord cut off. All the models had a maximum thickness of 4 1/2 inches to conform with average propeller-shank dimensions and a span of 20 1/4 inches. For the tests the models were supported perpendicular to the lower surface of the wing of an XP-51 airplane (p. 277). more
Date: June 7, 1946
Creator: Barlow, William H.
Partner: UNT Libraries Government Documents Department
open access

Flight investigation of the effect of various vertical-tail modifications on the directional stability and control characteristics of a propeller-driven fighter airplane

Description: "A flight investigation was made to determine the effect of various vertical-tail modifications and of some combinations of these modifications on the directional stability and control characteristics of a propeller-driven fighter airplane. Six different vertical-tail configurations were investigated to determine the lateral-directional oscillation characteristics, the sideslip characteristics, the yaw due to ailerons in rudder-fixed rolls from turns and pull-outs, the trim changes due to speed… more
Date: November 21, 1946
Creator: Johnson, Harold I.
Partner: UNT Libraries Government Documents Department
open access

Flight measurements of the lateral control characteristics of narrow-chord ailerons on the trailing edge of a full-span slotted flap

Description: From Summary: "Results are presented of light 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 investigation included determination of the rolling and yawing characteristics of the airplane in abrupt aileron rolls with the slotted flap at various settings ranging from 0 degree to about 40 degrees. The result… more
Date: October 25, 1946
Creator: Sawyer, Richard H.
Partner: UNT Libraries Government Documents Department
open access

Flutter and oscillating air-force calculations for an airfoil in two-dimensional supersonic flow

Description: A connected account is given of the Possio theory of non-stationary flow for small disturbances in a two-dimensional supersonic flow and of its application to the determination of the aerodynamic forces on an oscillating airfoil. Further application is made to the problem of wing flutter in the degrees of freedom - torsion, bending, and aileron rotations. Numerical tables for flutter calculations are provided for various values of the Mach number greater than unity. Results for bending-torsion … more
Date: May 29, 1946
Creator: Garrick, I. E. & Rubinow, S. I.
Partner: UNT Libraries Government Documents Department
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High-altitude flight cooling investigation of a radial air-cooled engine

Description: "An investigation of the cooling of an 18-cylinder, twin-row, radial, air-cooled engine in a high-performance pursuit airplane has been conducted for variable engine and flight conditions at altitudes ranging from 5000 to 35,000 feet in order to provide a basis for predicting high-altitude cooling performance from sea-level or low altitude experimental results. The engine cooling data obtained were analyzed by the usual NACA cooling-correlation method wherein cylinder-head and cylinder-barrel t… more
Date: May 9, 1946
Creator: Manganiello, Eugene J.; Valerino, Michael F. & Bell, E. Barton
Partner: UNT Libraries Government Documents Department
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An investigation of a thermal ice-prevention system for a twin-engine transport airplane

Description: Several previously published reports on a comprehensive investigation of a thermal ice-prevention system for a typical twin-engine transport airplane are correlated with some unpublished data to present the entire investigation in one publication. Several previously published reports on a comprehensive investigation of a thermal ice-prevention system for a typical twin-engine transport airplane are correlated with some unpublished data to present the entire investigation in one publication. The… more
Date: 1946
Creator: Jones, Alun R.
Partner: UNT Libraries Government Documents Department
open access

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

Description: "The laminar boundary layer and the position of the transition point were investigated on a heated flat plate. It was found that the Reynolds number of transition decreased as the temperature of the plate is increased. It is shown from simple qualitative analytical considerations that the effect of variable viscosity in the boundary layer due to the temperature difference produces a velocity profile with an inflection point if the wall temperature is higher than the free-stream temperature" (p.… more
Date: August 28, 1946
Creator: Liepmann, Hans W. & Fila, Gertrude H.
Partner: UNT Libraries Government Documents Department
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Jet-boundary and plan-form corrections for partial-span models with reflection-plane, end-plate, or no end-plate in a closed circular wind tunnel

Description: A method is presented for determining the jet-boundary and plan-form corrections necessary for application to test data for a partial-span model with a reflection plane, an end plate, or no end plate in a closed circular wind tunnel. Examples are worked out for a partial-span model with each of the three end conditions in the Langley 19-foot pressure tunnel and the corrections are applied to measured values of lift, drag, pitching-moment, rolling-moment, and yawing-moment coefficients.
Date: February 4, 1946
Creator: Sivells, James C. & Deters, Owen J.
Partner: UNT Libraries Government Documents Department
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The Lagrangian Multiplier Method of Finding Upper and Lower Limits to Critical Stresses of Clamped Plates

Description: "The theory of Lagrangian multipliers is applied to the problem of finding both upper and lower limits to the true compressive buckling stress of a clamped rectangular plate. The upper and lower limits thus bracket the truss, which cannot be exactly found by the differential-equation approach. The procedure for obtaining the upper limit, which is believed to be new, presents certain advantages over the classical Raleigh-Rite method of finding upper limits" (p. 1).
Date: 1946
Creator: Budiansky, Bernard & Hu, Pai C.
Partner: UNT Libraries Government Documents Department
open access

The Lagrangian Multiplier Method of Finding Upper and Lower Limits to Critical Stresses of Clamped Plates

Description: "The theory of Lagrangian multipliers is applied to the problem of finding both upper and lower limits to the true compressive buckling stress of a clamped rectangular plate. The upper and lower limits thus bracket the true stress, which cannot be exactly found by the differential-equation approach. The procedure for obtaining the upper limit, which is believed to be new, presents certain advantages over the classical Rayleigh-Ritz method of finding upper limits" (p. 213).
Date: May 3, 1946
Creator: Budiansky, Bernard & Hu, Pai C.
Partner: UNT Libraries Government Documents Department
open access

Measurements in Flight of the Pressure Distribution on the Right Wing of a Pursuit-Type Airplane at Several Values of Mach Number

Description: "Pressure-distribution measurements were made on the right wing of a pursuit-type airplane at values of Mach number up to 0.80. The results showed that a considerable portion of the lift was carried by components of the airplane other than the wings, and that the proportion of lift carried by the wings may vary considerably with Mach number, thus changing the bending moment at the wing root whether or not there is a shift in the lateral position of the center of pressure. It was also shown that… more
Date: 1946
Creator: Clousing, Lawrence A.; Turner, William N. & Rolls, L. Stewart
Partner: UNT Libraries Government Documents Department
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Method for calculating wing characteristics by lifting-line theory using nonlinear section lift data

Description: "A method is presented for calculating wing characteristics by lifting-line theory using nonlinear section lift data. Material from various sources is combined with some original work into the single complete method described. Multhopp's systems of multipliers are employed to obtain the induced angle of attack directly from the spanwise lift distribution. Equations are developed for obtaining these multipliers for any even number of spanwise stations, and values are tabulated for 10 stations al… more
Date: December 20, 1946
Creator: Sivells, James C. & Neely, Robert H.
Partner: UNT Libraries Government Documents Department
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