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Improvements in Heat Transfer for Anti-Icing of Gas-Heated Airfoils with Internal Fins and Partitions

Description: "The effect of modifying the gas passage of hollow metal airfoils by the addition of internal fins and partitions was experimentally investigated and comparisons were made among a basic unfinned airfoil section and two airfoil designs having metal fins attached at the leading edge of the internal gas passage. An analysis considering the effects of heat conduction in the airfoil metal was made to determine the internal modification effectiveness that may be obtained in gas-heated components, suc… more
Date: July 1950
Creator: Gray, Vernon H.
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.
Partner: UNT Libraries Government Documents Department
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A Probability Analysis of the Meteorological Factors Conducive to Aircraft Icing in the United States

Description: Note presenting meteorological icing data obtianed in flight in the United States that is analyzed statistically and used to develop methods for the determination of the various simultaneous combinations of the three basic icing parameters and the probability of exceeding any specified group of values of liquid-water content associated simultaneously with temperature and drop-diameter values. A mathematical basis is also provided for the future statistical analysis of meteorological icing data … more
Date: July 1952
Creator: Lewis, William & Bergrun, Norman R.
Partner: UNT Libraries Government Documents Department
open access

Icing Frequencies Experienced During Climb and Descent by Fighter-Interceptor Aircraft

Description: "Data and analyses are presented on the relative frequencies of occurrence and severity of icing cloud layers encountered by jet aircraft in the climb and descent phases of flights to high altitudes. Fighter-interceptor aircraft operated by the Air Defense Command (USAF) at bases in the Duluth and Seattle areas collected the data with icing meters installed for a 1-year period. The project was part of an extensive program conducted by the NACA to collect Icing cloud data for evaluating the icin… more
Date: July 1958
Creator: Perkins, Porter J.
Partner: UNT Libraries Government Documents Department
open access

Photomicrographic Investigation of Spontaneous Freezing Temperatures of Supercooled Water Droplets

Description: "A photomicrographic technique for investigating seupercooled water droplets has been devised and. used. to determine the spontaneous freezing temperatures of seupercooled water droplets of the size ordinarily found. in the atmosphere. The freezing temperatures of 4527 droplets ranging from 8.75 to 1000 microns in diameter supported on a platinum surface and 571 droplets supported on copper were obtained. The average spontaneous freezing temperature decreased with decrease in the size of the dr… more
Date: July 1950
Creator: Dorsch, Robert G. & Hacker, Paul T.
Partner: UNT Libraries Government Documents Department
open access

Study of Chromium-Frit-Type Coatings for High-Temperature Protection of Molybdenum

Description: "The achievement of more compact and efficient power plants for aircraft is dependent, among other factors, on the perfection of heat-resisting materials that are superior to those in current use. Molybdenum is one of the high-melting metals (melting point, 4750 F). It is fairly abundant and also can be worked into many of the shapes required in modern power plants. To permit its widespread use at elevated temperatures, however, some means must first be found to prevent its rapid oxidation" (p.… more
Date: July 1951
Creator: Moore, D. G.; Bolz, L. H.; Pitts, J. W. & Harrison, W. N.
Partner: UNT Libraries Government Documents Department
open access

Impingement of Water Droplets on NACA 65A004 Airfoil at 8 Degree Angle of Attack

Description: The trajectories of droplets in the air flowing past an NACA 65AO04 airfoil at an angle of attack of 8 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. These impingement characteristics are compared briefly with those previously reported for the … more
Date: July 1954
Creator: Brun, Rinaldo J.; Gallagher, Helen M. & Vogt, Dorothea E.
Partner: UNT Libraries Government Documents Department
open access

Handbook of Structural Stability Part 2: Buckling of Composite Elements

Description: "The local buckling of stiffener sections and the buckling of plates with sturdy stiffeners are reviewed, and the results are summarized in charts and tables. Numerical values of buckling coefficients are presented for longitudinally compressed stiffener sections of various shapes, for stiffened plates located in longitudinal compression and in shear, and for stiffened cylinders loaded in torsion. Although the data presented consist primarily of elastic-buckling coefficients, the effects of pla… more
Date: July 1957
Creator: Becker, Herbert
Partner: UNT Libraries Government Documents Department
open access

A Body Modification to Reduce Drag Due to Wedge Angle of Wing with Unswept Trailing Edge

Description: From Summary: "Ward's slender-body-theory formula for zero-lift drag contains three integrals plus a base-drag term. Two of these integral terms depend only upon the cross-sectional area distribution of the body. The third integral term depends only upon the body shape and axial slopes at the base of the body. This term is neglected in the transonic area rule because in many cases it is zero; however, there are also many cases in which it is not zero. This paper examines the term for the possib… more
Date: July 1958
Creator: Pitts, William C. & Nielsen, Jack Norman
Partner: UNT Libraries Government Documents Department
open access

The calculation of downwash behind wings of arbitrary plan form at supersonic speeds

Description: Report presenting exact and approximate methods based on linearized supersonic flow theory for the calculation of the velocity potential and the downwash from thin wings of arbitrary plan form. The applicability of the method inherently depends on a knowledge of the load distribution over the plan form of the wing.
Date: July 1950
Creator: Martin, John C.
Partner: UNT Libraries Government Documents Department
open access

Analytical and Experimental Investigation of Adiabatic Turbulent Flow in Smooth Tubes

Description: Note presenting equations derived for the prediction of velocity distributions for fully developed adiabtic turbulent flow in smooth tubes; both the incompressible and compressible flow cases were treated. The analysis produced a single equation that represents flow in both the conventional buffer layer and the laminar layer. The results for fully developed flow were correlated by using conventional dimensionless velocity and distance parameters, and agreed closely with those of Nikuradse and o… more
Date: July 1950
Creator: Deissler, Robert G.
Partner: UNT Libraries Government Documents Department
open access

Effect of Variation in Rivet Diameter and Pitch on the Average Stress at Maximum Load for 24S-T3 and 75S-T6 Aluminum-Alloy, Flat, Z-Stiffened Panels That Fail by Local Instability

Description: "A study is made of the effect of variation in diameter and pitch of A17S-T4 aluminum-alloy flat-head rivets on the average stress at maximum load for 24S-T3 and 75S-T6 aluminum-alloy, flat, Z-stiffened panels that fail by local instability. A curve is presented for determining the diameter and pitch required to insure the development of a given average stress for local instability" (p. 1).
Date: July 1950
Creator: Dow, Norris F. & Hickman, William A.
Partner: UNT Libraries Government Documents Department
open access

The theoretical characteristics of triangular-tip control surfaces at supersonic speeds: Mach lines behind trailing edges

Description: Report presenting generalized expressions in closed form obtained for the characteristics due to control-surface deflection and wing angle of attack for wing plan forms with triangular-tip control surfaces at supersonic speeds. Charts are presented for the deflection characteristics for configurations having the sweep of the wing and control-surface trailing edges equal and for the location of the hinge line for balanced controls.
Date: July 1952
Creator: Kainer, Julian H. & King, Mary Dowd
Partner: UNT Libraries Government Documents Department
open access

A rapid approximate method for determining velocity distribution on impeller blades of centrifugal compressors

Description: Report presenting the development of a rapid approximate method of analysis for both compressible and incompressible, nonviscous flow through radial- or mixed-flow centrifugal compressors with arbitrary hub and shroud contours and arbitrary blade shape. The method is used with eight numerical examples for two-dimensional flow, covering a wide range of flow rate, impeller-tip speed, number of blades, and blade curvature.
Date: July 1951
Creator: Stanitz, John D. & Prian, Vasily D.
Partner: UNT Libraries Government Documents Department
open access

Theoretical aerodynamic characteristics of bodies in a free-molecule-flow field

Description: Report presenting an investigation of the aerodynamic coefficients of various bodies located in a free-molecule-flow field. The bodies include a flat plate, a cylinder, a sphere, and a cone.
Date: July 1951
Creator: Stalder, Jackson R. & Zurick, Vernon J.
Partner: UNT Libraries Government Documents Department
open access

Flight investigation of the effect of transient wing response on wing strains of a twin-engine transport airplane in rough air

Description: Report presenting a flight investigation on a twin-engine transport airplane to determine the strains associated with the dynamic behavior of the wing during flights through rough air. Flights were made in clear-air turbulence for different wing fuel loads and for two speed conditions at a range of altitudes. Results indicated that the bending strains per unit normal acceleration in gusts were approximately 20 percent higher than those in slow pull-ups for all measuring positions and flight con… more
Date: July 1951
Creator: Mickleboro, Harry C. & Shufflebarger, Charles C.
Partner: UNT Libraries Government Documents Department
open access

Bench-Test Investigation of the Transient-Response Characteristics of Several Simulated Airplanes Incorporating an Autopilot Sensitive to Yawing Accelerations

Description: Note presenting testing of an autopilot sensitive to yawing acceleration, which was used to control four simulated airplane (mass-spring) configurations, and a series of bench tests to determine the response characteristics of the combinations.
Date: July 1951
Creator: Howard, Donald A.
Partner: UNT Libraries Government Documents Department
open access

Temperature distribution in internally heated walls of heat exchangers with noncircular flow passages using coolants with very low Prandtl number

Description: Report presenting a prediction of the magnitude of temperature variation in order to detect the places of highest temperature and to determine the operating temperatures admissible for the material of which the heat exchanger is composed. Results regarding the temperature distribution in triangular passages, temperature distribution in rectangular passages, influence of velocity field on temperature field, and a comparison of Prandtl number 1 solution are provided.
Date: July 1951
Creator: Eckert, E. R. G. & Low, George M.
Partner: UNT Libraries Government Documents Department
open access

Investigation of NACA 64,2-432 and 64,3-440 airfoil sections with boundary-layer control and an analytical study of their possible applications

Description: Report presenting testing of NACA 64-series airfoil sections to determine the effect of boundary-layer control by means of suction through an airfoil chord on the pressure distribution, lift, and drag characteristics of two different types of airfoil sections. Substantial reductions in wake drag were obtained through a wide range of lift coefficients with relatively moderate flow coefficients and pressure-loss coefficients. Results regarding airfoil-section data and effect of boundary-layer con… more
Date: July 1951
Creator: Horton, Elmer A.; Racisz, Stanley Frank & Paradiso, Nicholas J.
Partner: UNT Libraries Government Documents Department
open access

Method of Analysis for Compressible Flow Arbitrary Turbomachine Blades on General Surface of Revolution

Description: Note presenting a method of obtaining the flow of a nonviscous compressible fluid past arbitrary compressor or turbine blades between two neighboring surfaces of revolution. Satisfactory results were obtained by the method described in the investigation of the detailed flow variation of a compressible fluid past typical high-solidity, highly cambered thick turbine blades on a cylindrical surface.
Date: July 1951
Creator: Wu, Chung-Hua & Brown, Curtis A.
Partner: UNT Libraries Government Documents Department
open access

Approximate design method for high-solidity blade elements in compressors and turbines

Description: Note presenting an approximate blade-element design method for compressible or incompressible nonviscous flow in high-solidity stators or rotors of axial-, radial-, or mixed-flow compressors, turbines, or two-dimensional cascades. The method is based upon channel-type flow between blade elements on a specified surface of revolution that lies between the hub and shroud and is concentric with the axis of the compressor turbine.
Date: July 1951
Creator: Stanitz, John D.
Partner: UNT Libraries Government Documents Department
open access

Construction and Use of Charts in Design Studies of Gas Turbines

Description: "A method is presented for the computation and graphic representation of a series of possible turbine designs for any specific application. The use of a preliminary design chart is suggested for determining the number of stages and the effects of exit whirl and annular-area divergence on possible configurations. A specific design chart can then be made to aid in the study of the relations between turbine radius ratio, diameter, and significant design parameters such as Mach numbers, turning ang… more
Date: July 1951
Creator: Alpert, Sumner & Litrenta, Rose M.
Partner: UNT Libraries Government Documents Department
open access

The Indicial Lift and Pitching Moment for a Sinking or Pitching Two-Dimensional Wing Flying at Subsonic or Supersonic Speeds

Description: Report presenting solutions for the lift and pitching moment on a two-dimensional flat plate undergoing a step variation in pitch or vertical displacement. The results are subject to the restrictions of linearized, compressible-flow theory.
Date: July 1951
Creator: Lomax, Harvard; Heaslet, Max A. & Sluder, Loma
Partner: UNT Libraries Government Documents Department
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