National Advisory Committee for Aeronautics (NACA) - 4,107 Matching Results

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Effect of Type of Porous Surface and Suction Velocity Distribution on the Characteristics of a 10.5 Percent-Thick Airfoil With Area Suction

Description: Note presenting an investigation at low speed of the two-dimensional characteristics of a 10.51-percent-thick symmetric airfoil with area suction for boundary-layer control near the leading edge. The lift and suction-flow characteristics were determined with different porous surfaces consisting of perforated plates and sintered steel for various suction velocity distributions obtained by varying the permeability arrangement.
Date: December 1953
Creator: Dannenberg, Robert E. & Weiberg, James A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Resistance to Air Flow of Porous Materials Suitable for Boundary-Layer-Control Applications Using Area Suction

Description: "Measurements were made of the resistance to air flow of commercially available porous materials. Three general types of porous media were tested - granular (sintered materials), fibrous (felt cloths and filter papers), and perforated. The flow-resistance characteristics of the porous materials tested are presented in a form intended to assist in the selection of materials for applications to boundary-layer control using area suction" (p. 1).
Date: January 1954
Creator: Dannenberg, Robert E.; Weiberg, James A. & Gambucci, Bruno J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A flight investigation of the practical problems associated with porous-leading-edge suction

Description: From Summary: "A flight investigation has been made of the practical problems associated with the use of porous-leading-edge suction. The wing leading edge of the test airplane was porous over approximately 83 percent of the span and the first 8 percent of the chord on the upper surface. Various other extents of suction area within these limits were also tested."
Date: February 1954
Creator: Hunter, Paul A. & Johnson, Harold I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Fibrous-Glass Compact as a Permeable Material for Boundary-Layer-Control Applications Using Area Suction

Description: "Measurements were made of the resistance of fibrous-glass compacts to normal air flow. The flow resistance was related to the thickness and density. As a porous material for boundary-layer-control applications using area suction, the fibrous-glass compact could be made to any desired thickness and permeability and sandwiched between perforated rigid surfaces" (p. 1).
Date: January 1955
Creator: Dannenberg, Robert E.; Weiberg, James A. & Gambucci, Bruno J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A theoretical study of the effect of forward speed on the free-space sound-pressure field around propellers

Description: Report presenting an analysis of the sound-pressure field of a rotating propeller in forward flight in free space by replacing the normal-pressure distribution over the propeller associated with thrust and torque by a distribution of acoustic pressure doublets acting at the propeller disk. The result is presented for a moving and a fixed observer.
Date: 1954
Creator: Garrick, I. E. & Watkins, Charles E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analytical Investigation of Icing Limit for Diamond-Shaped Airfoil in Transonic and Supersonic Flow

Description: Calculations have been made for the icing limit of a diamond airfoil at zero angle of attack in terms of the stream Mach number, stream temperature, and pressure altitude. The icing limit is defined as a wetted-surface temperature of 320 F and is related to the stream conditions by the method of Hardy. The results show that the point most likely to ice on the airfoil lies immediately behind the shoulder and is subject to possible icing at Mach numbers as high as 1.4.
Date: January 1953
Creator: Callaghan, Edmund E. & Serafini, John S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Ice and Frost Formations on Drag of NACA 65(sub 1) -212 Airfoil for Various Modes of Thermal Ice Protection

Description: "The effects of primary and runback icing and frost formations on the drag of an 8-foot-chord NACA 651-212 airfoil section were investigated over a range of angles of attack from 20 to 80 and airspeeds up to 260 miles per hour for icing conditions with liquid-water contents ranging from 0.25 to 1.4 grams per cubic meter and datum air temperatures of -30 to 30 F. The results showed that glaze-ice formations, either primary or runback, on the upper surface near the leading edge of the airfoil cau… more
Date: June 1953
Creator: Gray, Vernon H. & von Glahn, Uwe H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Correlations Among Ice Measurements, Impingement Rates Icing Conditions, and Drag Coefficients for Unswept NACA 65A004 Airfoil

Description: "An empirical relation has been obtained by which the change in drag coefficient caused by ice formations on an unswept NACA 65A004 airfoil section can be determined from the following icing and operating conditions: icing time, airspeed, air total temperature, liquid-water content, cloud droplet impingement efficiencies, airfoil chord length, and angles of attack. The correlation was obtained by use of measured ice heights and ice angles. These measurements were obtained from a variety of ice … more
Date: February 1958
Creator: Gray, Vernon H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental Droplet Impingement on Four Bodies of Revolution

Description: An experiment was conducted to obtain the rate and area of cloud droplet impingement on four bodies of revolution was conducted in the icing tunnel with a dye-tracer technique. The study included several forebody shapes of different fineness ratios over a range of angles of attack and rotational speeds. Results regarding velocity distribution, local impingement characteristics, and correlation of impingement characteristics are provided.
Date: December 1957
Creator: Lewis, James P. & Ruggeri, Robert S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impingement of Cloud Droplets on 36.5-Percent-Thick Joukowski Airfoil at Zero Angle of Attack and Discussion of Use as Cloud Measuring Instrument in Dye-Tracer Technique

Description: "The trajectories of droplets in the air flowing past a 36.5-percent-thick Joukowski airfoil at zero angle of attack were determined. The amount of water in droplet form impinging on the airfoil, the area of droplet impingement, and the rate of droplet impingement per unit area on the airfoil surface were calculated from the trajectories and cover a large range of flight and atmospheric conditions. With the detailed impingement information available, the 36.5-percent-thick Joukowski airfoil can… more
Date: September 1957
Creator: Brun, R. J. & Vogt, Dorothea E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of heat transfer from a stationary and rotating ellipsoidal forebody of fineness ratio 3

Description: From Summary: "The convective heat transfer from the surface of an ellipsoidal forebody of fineness ratio 3 and 20-inch maximum diameter was investigated in clear air for both stationary and rotating operation over a range of conditions including air speeds up to 240 knots, rotational speeds up to 1200 rpm, and angles of attack of 0 deg, 3 deg, and 6 deg. The results are presented in the form of heat-transfer coefficients and the correlation of Nusselt and Reynolds numbers. Both a uniform surfa… more
Date: November 1956
Creator: Lewis, James P. & Ruggeri, Robert S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Heat Transfer from a Stationary and Rotating Conical Forebody

Description: From Summary: "The convective heat transfer from the surface of a conical forebody having a hemispherical nose, an included angle of approximately 30 deg, and. a maximum diameter of 18.9 inches was investigated in a wind tunnel for both stationary and. rotating operation. The range of test conditions included free-stream velocities up to 400 feet per second, rotational speeds up to 1200 rpm, and. angles of attack of 0 deg and 6 deg. Both a uniform surface temperature and a uniform heater input … more
Date: October 1957
Creator: Ruggeri, Robert S. & Lewis, James P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Calculation of the Heat Required for Wing Thermal Ice Prevention in Specified Icing Conditions

Description: Note presenting a verification of previously derived equations for calculating the rate of heat transfer from airfoils in icing conditions, which have come about as a result of an investigation of the meteorological conditions conducive to the formation of ice on aircraft and a study of the process of airfoil thermal ice prevention. The results indicated that knowledge of these components has increased to a point where the design of heated wings on a fundamental, wet-air basis can now be undert… more
Date: December 1947
Creator: Neel, Carr B., Jr.; Bergrun, Norman R.; Jukoff, David & Schlaff, Bernard A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Empirical Method Permitting Rapid Determination of the Area, Rate and Distribution of Water-Drop Impingement on an Airfoil of Arbitrary Section at Subsonic Speeds

Description: "An empirical method for the determination of the area, rate, and distribution of water-drop impingement on airfoils of arbitrary section is presented. The procedure represents an initial step toward the development of a method which is generally applicable in the design of thermal ice-prevention equipment for airplane wing and tail surfaces. Results given by the proposed empirical method are expected to be sufficiently accurate for the purpose of heated-wing design, and can be obtained from a … more
Date: September 1951
Creator: Bergrun, Norman R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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 calculatio… more
Date: August 1947
Creator: Bergrun, Norman R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impingement of droplets in 90 degree elbows with potential flow

Description: Trajectories were determined for droplets in air flowing through 90 deg elbows especially designed for two-dimensional potential motion with low pressure losses. The elbows were established by selecting as walls of each elbow two streamlines of the flow field produced by a complex potential function that establishes a two-dimensional flow around a 90 deg bend. An unlimited number of elbows with slightly different shapes can be established by selecting different pairs of streamlines as walls. Th… more
Date: September 1953
Creator: Hacker, Paul T.; Brun, Rinaldo J. & Boyd, Bemrose
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impingement of Water Droplets on NACA 65A004 Airfoil and Effect of Change in Airfoil Thickness from 12 to 4 Percent at 4 deg Angle of Attack

Description: From Summary: "The trajectories of droplets in the air flowing past an NACA 65A004 airfoil at an angle of attack of 4 deg were determined. The amount of water in droplet form impinging on the airfoil, the area of droplet impingement, and the rate of droplet impingement per unit area on the airfoil surface were calculated from the trajectories and presented to cover a large range of flight and atmospheric conditions. The effect of a change in airfoil thickness from 12 to 4 percent at 4 deg angle… more
Date: November 1953
Creator: Brun, Rinaldo J.; Gallagher, Helen M. & Vogt, Dorothea E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impingement of Water Droplets on NACA 65(1)-208 and 65(1)-212 Airfoils at 4 Degrees Angle of Attack

Description: "The trajectories of droplets in the air flowing past NACA 65(1)-208 airfoil and an NACA 65(1)-212 airfoil, both at an angle of attack of 4 degrees, were determined. The amount of water in droplet form impinging on the airfoils, the area of droplet impingement, and the rate of droplet impingement per unit area on the airfoil surface affected were calculated from the trajectories and are presented. The amount, extent, and rate of impingement of the NACA 65(1)-208 airfoil are compared with the re… more
Date: May 1953
Creator: Brun, Rinaldo J.; Gallagher, Helen M. & Vogt, Dorothea E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impingement of Water Droplets on a Cylinder in an Incompressible Flow Field and Evaluation of Rotating Multicylinder Method for Measurement of Droplet-Size Distribution, Volume-Median Droplet-Size, and Liquid-Water Content in Clouds

Description: Note presenting an evaluation of the rotating method for the measurement of droplet-size distribution, volume-median droplet size, and liquid-water content in clouds, which showed that small uncertainties in basic data eliminate the distinction between cloud droplet-size distributions and are a source of large errors in the determination of the droplet size. Matching curves for obtaining droplet-size distribution, volume-median droplet size, and liquid-water content from flight data were comput… more
Date: March 1953
Creator: Brun, Rinaldo J. & Mergler, Harry W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impingement of Cloud Droplets on Aerodynamic Bodies as Affected by Compressibility of Air Flow Around the Body

Description: Note presenting the computation of the trajectories of water droplets in a compressible-air flow field around a cylinder using a mechanical analog. The results of the calculations at approximately the flight critical Mach number were compared with calculations of trajectories in an incompressible flow field. Results regarding the extension of cylinder results to airfoils are provided.
Date: March 1953
Creator: Brun, Rinaldo J.; Serafini, John S. & Gallagher, Helen M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Method for Determining Cloud-Droplet Impingement on Swept Wings

Description: From Summary: "The general effect of wing sweep on cloud-droplet trajectories about swept wings of high aspect ratio moving at subsonic speeds is discussed. A method of computing droplet trajectories about yawed cylinders and swept wings is presented, and illustrative droplet trajectories are computed. A method of extending two-dimensional calculations of droplet impingement on nonswept wings to swept wings is presented."
Date: April 1953
Creator: Dorsch, Robert G. & Brun, Rinaldo J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impingement of Water Droplets on an Ellipsoid with Fineness Ratio 5 in Axisymmetric Flow

Description: "The presence of radomes and instruments that are sensitive to water films or ice formations in the nose section of all-weather aircraft and missiles necessitates a knowledge of the droplet impingement characteristics of bodies of revolution. Because it is possible to approximate many of these bodies with an ellipsoid of revolution, droplet trajectories about an ellipsoid of revolution with a fineness ratio of 5 were computed for incompressible axisymmetric air flow. From the computed droplet t… more
Date: March 1954
Creator: Dorsch, Robert G.; Brun, Rinaldo J. & Gregg, John L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Variation of Local Liquid-Water Concentration About and Ellipsoid of Fineness Ratio 5 Moving in a Droplet Field

Description: From Summary: "Trajectories of water droplets about an ellipsoid of revolution with a fineness ratio of 5 (which often approximates the shape of an aircraft fuselage or missile) were computed with the aid of a differential analyzer. Analyses of these trajectories indicate that the local concentration of liquid water at various points about an ellipsoid in flight through a droplet field varies considerably and under some conditions may be several times the free-stream concentration."
Date: July 1954
Creator: Dorsch, Robert G. & Brun, Rinaldo J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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