National Advisory Committee for Aeronautics (NACA) - 13,786 Matching Results

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New Method of Determining the Polar Curve of an Airplane in Flight

Description: "A fundamental defect of existing methods for the determination of the polar of an airplane in flight is the impossibility of obtaining the thrust or the resistance of the propeller for any type airplane with any type engine. The new method is based on the premise that for zero propeller thrust the mean angle of attack of the blade is approximately the same for all propellers if this angle is reckoned from the aerodynamic chord of the profile section. This angle was determined from flight tests… more
Date: March 1945
Creator: Yegorov, B. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Deflections of a Simply Supported Rectangular Sandwich Plate Subjected to Transverse Loads

Description: "The differential equations of the bending of sandwich plates were integrated to obtain the deflections when the four edges of the plate are simply supported and the loading consists of either a uniformly distributed transverse load or a concentrated load applied at the center of the panel. The deflection patterns are shown in diagrams and the maximum deflection of the plate is presented in a number of graphs" (p. 1).
Date: December 1951
Creator: Yen, Kuo Tai; Gunturkun, Sadettin & Pohle, Frederick V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Buckling of rectangular sandwich plates subjected to edgewise compression with loaded edges simply supported and unloaded edges clamped

Description: Report presenting the compressive stress for buckling for a rectangular flat sandwich plate with loaded edges simply supported and unloaded edges rigidly clamped. The true values of the buckling stress are estimated as the arithmetic means of these bounds and are presented in a diagram which covers the entire practical range of the geometric and mechanical quantities involved.
Date: January 1952
Creator: Yen, Kuo Tai; Salerno, V. L. & Hoff, N. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermal-Shock Resistance of a Ceramic Comprising 60 Percent Boron Carbide and 40 Percent Titanium Diboride

Description: Thermal-shock resistance of a ceramic comprising 60 percent boron carbide and 40 percent titanium diboride was investigated. The material has thermal shock resistance comparable to that of NBS body 4811C and that of zirconia, but is inferior to beryllia, alumina, and titanium-carbide ceramals. It is not considered suitable for turbine blades.
Date: March 16, 1953
Creator: Yeomans, C. M. & Hoffman, C. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rapid Estimation of Bending Frequencies of Rotating Beams

Description: Memorandum presenting a procedure in the form of charts which permits the rapid estimation of the natural bending frequencies of helicopter rotor blades, both rotating and nonrotating. An evaluation of the method with regard to such things as higher modes, blade offset, and variable mass and stiffness distributions is also given. The valuation shows that, when nonrotating beam bending modes are used, Southwell's equation yields reasonably accurate bending frequencies for rotating helicopter bla… more
Date: August 18, 1954
Creator: Yntema, Robert T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simplified Procedures and Charts for the Rapid Estimation of Bending Frequencies of Rotating Beams

Description: Note presenting a Rayleigh energy approach utilizing the bending mode of the nonrotating beam in the determination of the bending frequency of the rotating beam, which is evaluated and is found to give good practical results for helicopter blades. Charts are presented for the rapid estimation of the first three bending frequencies for rotating and nonrotating cantilever and hinged beams.
Date: June 1955
Creator: Yntema, Robert T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Impulse-Momentum Method for Calculating Landing-Gear Contact Conditions in Eccentric Landings

Description: "An impulse-momentum method for determining impact conditions for landing gears in eccentric landings is presented. The analysis is primarily concerned with the determination of contact velocities for impacts subsequent to initial touchdown in eccentric landings and with the determination of the effective mass acting on each landing gear. These parameters determine the energy-absorption requirements for the landing gear and, in conjunction with the particular characteristics of the landing gear… more
Date: January 1952
Creator: Yntema, Robert T. & Milwitzky, Benjamin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A method for rapid selection of design characteristics of 1-, 1 1/2-, and 2-stage turbines with optimum annulus taper

Description: Report presenting a method for the rapid selection of a turbine design within specified aerodynamic limits. Tables are provided with the overall design parameters and velocity-diagram variables of each design. Detailed design information is also included for ranges of blade-speed parameter and exit radius ratio.
Date: February 18, 1958
Creator: Yohner, Peggy L. & English, Robert E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some numerical solutions of similarity equations for three-dimensional laminar incompressible boundary-layer flows

Description: From Summary: "Numerical solutions are presented for two classes of similarity equations corresponding to a range of three-dimensional boundary-layer flows. Equations for limiting-flow deflection and equations for the calculation of boundary-layer streamlines are also presented."
Date: September 1958
Creator: Yohner, Peggy L. & Hansen, Arthur G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Mechanism of Buckling of a Circular Cylindrical Shell Under Axial Compression

Description: The present paper deals with the buckling of a circular cylindrical shell under axial compression from the viewpoint of energy and the characteristics of deformation. It is shown first, both theoretically and experimentally, that the reason why the buckling of a cylindrical shell is quite different from that of a flat plate is attributable to the existence of a nearly developable surface far apart from the original cylindrical surface. Based upon this result, the experimental fact that the buck… more
Date: July 1955
Creator: Yoshimura, Yoshimaru
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of Aluminum Deformation by Electron Microscopy

Description: Note presenting an investigation of the slip-line structure in a series of aluminum single crystals deformed in tension in an electron microscope. In several of the crystals, the slip-line structure was examined after successive steps in the elongation.
Date: August 1956
Creator: Young, A. P.; Melton, C. W. & Schwartz, C. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of performance of 9-cylinder engine using large valve overlap and eclipse fuel-injection system

Description: Report presenting single-cylinder tests were made with several different engines over a period of time, which have shown that a large overlap between the time of inlet valve opening and exhaust valve closing results in a considerable increase in the maximum power obtainable from a supercharged engine and reduces cylinder temperatures.
Date: November 1941
Creator: Young, Alfred W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Power Unit for High-Intensity Light Source

Description: "A light-source power unit has been developed that provides reliable trigger, and easy synchronization with rotating elements or electric impulses. When used with conventional spark gaps and flash tubes, this power unit provides a light pulse of high intensity and short duration" (p. 1).
Date: July 9, 1951
Creator: Young, Allen E.; McCullough, Stuart & Smith, Richard L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental Study of Isothermal Wake-Flow Characteristics of Various Flame-Holder Shapes

Description: "An investigation of the isothermal wake-flow characteristics of several flame-holder shapes was carried out in a 4- by 4-inch flow chamber. The effects of flame-holder-shape changes on the characteristics of the Karman vortices and thus on the recirculation zones to which experimenters have related the combustion process were obtained for several flame holders. The results may furnish a basis of correlation, of combustion efficiency and stability for similarly shaped flame holders in combustio… more
Date: January 23, 1952
Creator: Younger, George G.; Gabriel, David S. & Mickelsen, William R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Short Method of Calculating Torsional Stresses in an Airplane Fuselage

Description: "This report deals with an investigation carried out in the Civil Engineering Laboratory of the University of California, to determine the accuracy of existing methods of computing the stresses in an airplane fuselage when subjected to torsion, and to derive a simple approximate formula for the rapid calculation of these stresses. The formula is derived by using the customary least work equation and considering each bay separately" (p. 1).
Date: September 1924
Creator: Younger, John E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Vortex Sound from Rotating Rods

Description: "The motion of different bodies immersed in liquid or gaseous media is accompanied by characteristic sound which is excited by the formation of unstable surfaces of separation behind the body, usually disintegrating into a system of discrete vortices (such as the Karman vortex street due to the flow about an infintely long rod, etc.). In the noise from fans, pumps, and similar machinery, vortex noise frequently predominates. The purpose of this work is to elucidate certain questions of the depe… more
Date: March 1947
Creator: Yudin, E. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An automatic speed control for wind tunnels

Description: Described here is an automatic control that has been used in several forms in wind tunnels at the Washington Navy Yard. The form now in use with the 8-foot tunnel at the Navy Yard is considered here. Details of the design and operation of the automatic control system are given. Leads from a Pitot tube are joined to an inverted cup manometer located above a rheostat. When the sliding weight of this instrument is set to a given notch, say for 40 m.p.h, the beam tip vibrates between two electric c… more
Date: February 1928
Creator: Zahm, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of Air Speed Nozzles

Description: Report describes the development of a suitable speed nozzle for the first few thousand airplanes made by the United States during the recent war in Europe, and to furnish a basis for more mature instruments in the future. Requirements for the project were to provide a suitable pressure collector for aircraft speed meters and to develop a speed nozzle which would be waterproof, powerful, unaffected by slight pitch and yaw, rugged and easy to manufacture, and uniform in structure and reading, so … more
Date: 1920
Creator: Zahm, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flow and Drag Formulas for Simple Quadrics

Description: The pressure distribution and resistance found by theory and experiment for simple quadrics fixed in an infinite uniform stream of practically incompressible fluid are calculated. The experimental values pertain to air and some liquids, especially water; the theoretical refer sometimes to perfect, again to viscid fluids. Formulas for the velocity at all points of the flow field are given. Pressure and pressure drag are discussed for a sphere, a round cylinder, the elliptic cylinder, the prolate… more
Date: December 1979
Creator: Zahm, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flow and Drag Formulas for Simple Quadrics

Description: This report gives the pressure distribution and resistance found by theory and experiment for simple quadrics fixed in an infinite uniform stream of practically incompressible fluid. The experimental values pertain to air and some liquids, especially water; the theoretical refer sometimes to perfect, again to viscid fluids. For the cases treated the concordance of theory and measurement is so close as to make a resume of results desirable. Incidentally formulas for the velocity at all points of… more
Date: 1927
Creator: Zahm, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flow and Force Equations for a Body Revolving in a Fluid

Description: A general method for finding the steady flow velocity relative to a body in plane curvilinear motion, whence the pressure is found by Bernoulli's energy principle is described. Integration of the pressure supplies basic formulas for the zonal forces and moments on the revolving body. The application of the steady flow method for calculating the velocity and pressure at all points of the flow inside and outside an ellipsoid and some of its limiting forms is presented and graphs those quantities … more
Date: December 1979
Creator: Zahm, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flow and Force Equations for a Body Revolving in a Fluid

Description: Part I gives a general method for finding the steady-flow velocity relative to a body in plane curvilinear motion, whence the pressure is found by Bernoulli's energy principle. Integration of the pressure supplies basic formulas for the zonal forces and moments on the revolving body. Part II, applying this steady-flow method, finds the velocity and pressure at all points of the flow inside and outside an ellipsoid and some of its limiting forms, and graphs those quantities for the latter forms.… more
Date: December 17, 1928
Creator: Zahm, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Horizontal Buoyancy in Wind Tunnels

Description: Note presenting an examination of horizontal buoyancy in wind tunnels, including an examination of the relative flow, static pressure gradient, horizontal buoyancy computation, and methods of computation in practical use are provided.
Date: November 1920
Creator: Zahm, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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