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Exact solutions of laminar-boundary-layer equations with constant property values for porous wall with variable temperature

Description: From Summary: "Exact solution of the laminar-boundary-layer equations for wedge-type flow with constant property values are presented for transpiration-cooled surfaces with variable wall temperatures. The difference between wall and stream temperature is assumed proportional to a power of the distance from the leading edge. Solutions are given for a Prandtl number of 0.7 and ranges of pressure-gradient, cooling-air-flow, and wall-temperature-gradient parameters. Boundary-layer profiles, dimensi… more
Date: July 15, 1954
Creator: Donoughe, Patrick L. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department
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Theory of wing-body drag at supersonic speeds

Description: "The relation of Whitcomb's "area rule" to the linear formulas for wave drag at lightly supersonic speeds is discussed. By adopting an approximate relation between the source strength and the geometry of a wing-body combination, the wave-drag theory is expressed in terms involving the areas intercepted by oblique planes or Mach planes. The resulting formulas are checked by comparison with the drag measurements obtained in wind-tunnel experiments and in experiments with falling models in free ai… more
Date: July 8, 1953
Creator: Jones, Robert T.
Partner: UNT Libraries Government Documents Department
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The Effect of Increased Cooling Surface on Performance of Aircraft-Engine Cylinders as Shown by Tests of the NACA Cylinder

Description: A method of constructing fins of nearly optimum proportions has been developed by the NACA to the point where a cylinder has been manufactured and tested. Data were obtained on cylinder temperature for a wide range of inlet-manifold pressures, engine speeds, and cooling-pressure differences. The results indicate that an improvement of 40 percent in the outside-wall heat-transfer coefficient could be realized on the present NACA cylinder by providing a thermal bond equivalent to that of an integ… more
Date: July 1, 1944
Creator: Schey, Oscar W.; Rollin, Vern G. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
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Compressibility and Heating Effects on Pressure Loss and Cooling of a Baffled Cylinder Barrel

Description: "Theoretical investigations have shown that, because air is compressible, the pressure-drop requirements for cooling an air-cooled engine will be much greater at high altitudes and high speeds than at sea level and low speeds. Tests were conducted by the NACA to obtain some experimental confirmation of the effect of air compressibility on cooling and pressure loss of a baffled cylinder barrel and to evaluate various methods of analysis. The results reported in the present paper are regarded as … more
Date: July 1, 1944
Creator: Goldstein, Arthur W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
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The Flow of a Compressible Fluid Past a Circular Arc Profile

Description: "The Ackeret iteration process is utilized to obtain higher approximations than that of Prandtl and Glauert for the flow of a compressible fluid past a circular arc profile. The procedure is to expand the velocity potential in a power series of the camber coefficient. The first two terms of the development correspond to the Prandtl-Glauert approximation and yield the well-known correction to the circulation about the profile" (p. 385).
Date: July 15, 1944
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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Pressure distribution over an NACA 23012 airfoil with a fixed slot and a slotted flap

Description: Report presents the results of a pressure-distribution investigation conducted in the Langley Memorial Aeronautical Laboratory 7 by 10-foot wind tunnel to determine the air loads on an NACA 23012 airfoil in combination with a fixed leading-edge slot and a slotted flap. Pressures were measured over the upper and lower surfaces of the component parts of the combination for several angles of attack and at several flap settings. The data, presented as pressure diagrams and graphs of section coeffic… more
Date: July 30, 1941
Creator: Harris, Thomas A. & Lowry, John G.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Tests of Four- and Six-Blade Single- and Dual-Rotating Tractor Propellers

Description: "Test of 10-foot diameter, four and six blade single-rotating and dual-rotating propellers were conducted in the NACA propeller-research tunnel. The propellers were mounted at the front end of a streamline body incorporating spinners to house the hub portions. The effect of a symmetrical wing mounted in the slipstream ranged from 20 degrees to 65 degrees setting corresponds to airplane speeds greater than 500 miles per hour. The results indicate that dual-rotating propellers were from 0 to 6 pe… more
Date: July 13, 1942
Creator: Biermann, David & Hartman, Edwin P.
Partner: UNT Libraries Government Documents Department
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Prediction of the Effects of Propeller Operation on the Static Longitudinal Stability of Single-Engine Tractor Monoplanes with Flaps Retracted

Description: "The effects of propeller operation on the static longitudinal stability of single-engine tractor monoplanes are analyzed, and a simple method is presented for computing power-on pitching-moment curves for flap-retracted flight conditions. The methods evolved are based on the results of powered-model wind-tunnel investigations of 28 model configurations. Correlation curves are presented from which the effects of power on the downwash over the tail and the stabilizer effectiveness can be rapidly… more
Date: July 13, 1948
Creator: Weil, Joseph & Sleeman, William C., Jr.
Partner: UNT Libraries Government Documents Department
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Summary of Drag Characteristics of Practical-Construction Wing Sections

Description: "The effect of several parameters on the drag characteristics of practical-construction wing sections have been considered and evaluated. The effects considered were those of surface roughness, surface waviness, compressive load, and de-icers. The data were obtained from a number of tests in the Langley two-dimensional low-turbulence tunnels" (p. 359).
Date: July 11, 1946
Creator: Quinn, John H., Jr.
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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Effects of sweepback on boundary layer and separation

Description: "Following a law of stress adopted in the Navier-Stokes equations, the configuration of the viscous flow in planes at right angles to the axis of an infinite cylinder is found to be independent of the axial motion of the cylinder. In the limiting case of a yawed or swept wing of very high aspect ratio, certain boundary-layer and separation phenomena are thus determined independently by the crosswise component of velocity. It follows that the effect of sweepback is to increase the area of stable… more
Date: July 1947
Creator: Jones, Robert T.
Partner: UNT Libraries Government Documents Department
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The effect of mass distribution on the lateral stability and control characteristics of an airplane as determined by tests of a model in the free-flight tunnel

Description: The effects of mass distribution on lateral stability and control characteristics of an airplane have been determined by flight tests of a model in the NACA free-flight tunnel. In the investigation, the rolling and yawing moments of inertia were increased from normal values to values up to five times normal. For each moment-of-inertia condition, combinations of dihedral and vertical-tail area representing a variety of airplane configurations were tested. The results of the flight tests of the m… more
Date: July 20, 1943
Creator: Campbell, John P. & Seacord, Charles L., Jr.
Partner: UNT Libraries Government Documents Department
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Analysis of Heat and Compressibility Effects in Internal Flow Systems and High-Speed Tests of a Ram-Jet System

Description: Report discussing an analysis has been made by the NACA of the effects of heat and compressibility in the flow through the internal systems of aircraft along with equations and charts are developed whereby the flow characteristics at key stations in a typical internal system may be readily obtained.
Date: July 21, 1942
Creator: Becker, John V. & Baals, Donald D.
Partner: UNT Libraries Government Documents Department
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Charts for the Minimum-Weight Design of 24S-T Aluminum-Alloy Flat Compression Panels With Longitudinal Z-Section Stiffeners

Description: "Design charts are developed for 24S-T aluminum-alloy flat compression panels with longitudinal z-section stiffeners. These charts make possible the design of the lightest panels of this type for a wide range of design requirements. Examples of the use of the charts are given and it is pointed out on the basis of these examples that, over a wide range of design conditions, the maintenance of buckle-free surfaces does not conflict with the achievement of high structural efficiency" (p. 553).
Date: July 9, 1945
Creator: Schuette, Evan H.
Partner: UNT Libraries Government Documents Department
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Standard nomenclature for airspeeds with tables and charts for use in calculation of airspeed

Description: Symbols and definition of various airspeed terms that have been adopted as standard by the NACA subcommittee on aircraft structural design are presented. The equations, charts, and tables required in the evaluation of true airspeed, calibrated airspeed, equivalent airspeed, impact and dynamic pressures, and Mach and Reynolds numbers have been compiled. Tables of the standard atmosphere to an altitude of 65,000 feet and a tentative extension to an altitude of 100,000 feet are given along with th… more
Date: July 17, 1946
Creator: Aiken, William S., Jr.
Partner: UNT Libraries Government Documents Department
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Relative importance of various sources of defect-producing hydrogen introduced into steel during application of vitreous coatings

Description: "When porcelain enamels or vitreous-type ceramic coatings are applied to ferrous metals, there is believed to be an evolution of hydrogen gas both during and after the firing operation. At elevated temperatures rapid evolution may result in blistering while if hydrogen becomes trapped in the steel during the rapid cooling following the firing operation gas pressures may be generated at the coating-metal interface and flakes of the coating literally blown off the metal. To determine experimental… more
Date: July 12, 1951
Creator: Moore, Dwight G.; Mason, Mary A. & Harrison, William N.
Partner: UNT Libraries Government Documents Department
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The Linearized Characteristics Method and Its Application to Practical Nonlinear Supersonic Problems

Description: "The methods of characteristics has been linearized by assuming that the flow field can be represented as a basic flow field determined by nonlinearized methods and a linearized superposed flow field that accounts for small changes of boundary conditions. The method has been applied to two-dimensional rotational flow where the basic flow is potential flow and to axially symmetric problems where conical flows have been used as the basic flows. In both cases the method allows the determination of… more
Date: July 24, 1951
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department
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Design of two-dimensional channels with prescribed velocity distributions along the channel walls

Description: "A general method of design is developed for two-dimensional unbranched channels with prescribed velocities as a function of arc length along the channel walls. The method is developed for both compressible and incompressible, irrotational, nonviscous flow and applies to the design of elbows, diffusers, nozzles, and so forth. In part I solutions are obtained by relaxation methods; in part II solutions are obtained by a Green's function. Five numerical examples are given in part I including thre… more
Date: July 25, 1951
Creator: Stanitz, John D.
Partner: UNT Libraries Government Documents Department
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Dynamics of a turbojet engine considered as a quasi-static system

Description: From Summary: "A determination of the dynamic characteristics of a typical turbojet engine with a centrifugal compressor, a sonic-flow turbine-nozzle diaphragm, and fixed area exhaust nozzle is presented. A generalized equation for transient behavior of the engine was developed; this equation was then verified by calculations using compressor and turbine performance charts extrapolated from equilibrium operating data and by experimental data obtained from an engine operated under transients in … more
Date: July 27, 1949
Creator: Otto, Edward W. & Taylor, Burt L., III
Partner: UNT Libraries Government Documents Department
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Analysis of Turbulent Free-Convection Boundary Layer on Flat Plate

Description: "With the use of Karman's integrated momentum equation for the boundary layer and data on the wall-shearing stress and heat transfer in forced-convection flow, a calculation was carried out for the flow and heat transfer in the turbulent free-convection boundary layer on a vertical flat plate. The calculation is for a fluid with a Prandtl number that is close to 1. A formula was derived for the heat-transfer coefficient that was in good agreement with experimental data in the range of Grashof n… more
Date: July 12, 1950
Creator: Eckert, E. R. G. & Jackson, Thomas W.
Partner: UNT Libraries Government Documents Department
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Characteristics of the Langley 8-Foot Transonic Tunnel With Slotted Test Section

Description: "A large wind tunnel, approximately 8 feet in diameter, has been converted to transonic operation by means of slots in the boundary extending in the direction of flow. The usefulness of such a slotted wind tunnel, already known with respect to the reduction of the subsonic blockage interference and the production of continuously variable supersonic flows, has been augmented by devising a slot shape with which a supersonic test region with excellent flow quality could be produced. Experimental l… more
Date: July 3, 1958
Creator: Wright, Ray H.; Ritchie, Virgil S. & Pearson, Albin O.
Partner: UNT Libraries Government Documents Department
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Elliptic Cones Alone and with Wings at Supersonic Speed

Description: "To help fill the gap in the knowledge of aerodynamics of shapes intermediate between bodies of revolution and flat triangular wings, force and moment characteristics for elliptic cones have been experimentally determined for Mach numbers of 1.97 and 2.94. Elliptic cones having cross-sectional axis ratios from 1 through 6 and with lengths and base areas equal to circular cones of fineness ratios 3.67 and 5 have been studied for angles of bank of 0 degree and 90 degrees. Elliptic and circular co… more
Date: July 17, 1957
Creator: Jorgensen, Leland H.
Partner: UNT Libraries Government Documents Department
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Measurements of free-space oscillating pressures near propellers at flight Mach numbers to 0.72

Description: "In the course of a short flight program initiated to check the theory of Garrick and Watkins (NACA rep. 1198), a series of measurements at three stations were made of the oscillating pressures near a tapered-blade plan-form propeller and rectangular-blade plan form propeller at flight Mach numbers up to 0.72. In contradiction to the results for the propeller studied in NACA rep. 1198, the oscillating pressures in the plane ahead of the propeller were found to be higher than those immediately b… more
Date: July 1, 1958
Creator: Kurbjun, Max C. & Vogeley, Arthur W.
Partner: UNT Libraries Government Documents Department
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Comparison of effectiveness of convection-, transpiration-, and film-cooling methods with air as coolant

Description: From Summary: "Various parts of aircraft propulsion engines that are in contact with hot gases often require cooling. Transpiration and film cooling, new methods that supposedly utilize cooling air more effectively than conventional convection cooling, have already been proposed. This report presents material necessary for a comparison of the cooling requirements of these three methods. Correlations that are regarded by the authors as the most reliable today are employed in evaluating each of t… more
Date: July 9, 1953
Creator: Eckert, E. R. G. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department
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