UNT Libraries Government Documents Department - 37 Matching Results

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Analysis of effect of basic design variables on subsonic axial-flow-compressor performance

Description: From Summary: "A blade-element theory for axial-flow compressors has been developed and applied to the analysis of the effects of basic design variables such as Mach number, blade loading, and velocity distribution on compressor performance. The relations among several efficiencies useful in compressor design are derived and discussed. The possible gains in useful operating range obtainable by the use of adjustable stator blades are discussed and a rapid approximate method of calculating blade-… more
Date: November 26, 1947
Creator: Sinnette, John T., Jr.
Item Type: Refine your search to only Report
open access

Analysis of Performance of Jet Engine From Characteristics of Components 1: Aerodynamic and Matching Characteristics of Turbine Component Determined With Cold Air

Description: "The performance of the turbine component of an NACA research jet engine was investigated with cold air. The interaction and the matching of the turbine with the NACA eight-stage compressor were computed with the combination considered as a jet engine. The over-all performance of the engine was then determined. The internal aerodynamics were studied to the extent of investigating the performance of the first stator ring and its influence on the turbine performance" (p. 397).
Date: June 6, 1947
Creator: Goldstein, Arthur W.
Item Type: Refine your search to only Report
open access

An Analysis of the Full-Floating Journal Bearing

Description: Report discussing an analysis of the operating characteristics of a full-floating journal bearing, a bearing in which a floating sleeve is located between the journal and bearing surfaces, is presented together with charts from which the performance of such bearings may be predicted.
Date: January 1, 1947
Creator: Shaw, M. C. & Nussdorfer, T. J., Jr.
Item Type: Refine your search to only Report
open access

Critical Stress of Thin-Walled Cylinders in Axial Compression

Description: Empirical design curves are presented for the critical stress of thin-wall cylinders loaded in axial compression. These curves are plotted in terms of the nondimensional parameters of small-deflection theory and are compared with theoretical curves derived for the buckling of cylinders with simply supported and clamped edges. An empirical equation is given for the buckling of cylinders having a length-radius ratio greater than about 0.75.
Date: March 20, 1947
Creator: Batdorf, S. B.; Schildcrout, Murry & Stein, Manuel
Item Type: Refine your search to only Report
open access

Damping in pitch and roll of triangular wings at supersonic speeds

Description: A method is derived for calculating the damping coefficients in pitch and roll for a series of triangular wings and a restricted series of sweptback wings at supersonic speeds. The elementary "supersonic source" solution of the linearized equation of motion is used to find the potential function of a line of doublets, and the flows are obtained by surface distributions of these doublet lines. The damping derivatives for triangular wings are found to be a function of the ratio of the tangent of … more
Date: December 12, 1947
Creator: Brown, Clinton E. & Adams, Mac C.
Item Type: Refine your search to only Report
open access

Design and performance of family of diffusing scrolls with mixed-flow impeller and vaneless diffuser

Description: A family of diffusing scrolls was designed for use with a mixed-flow impeller and a small-diameter vaneless diffuser. The design theory, intended to maintain a uniform pressure around the scroll inlet, permits determination of the position of scroll cross sections of preassigned area by considering the radial variation in fluid density and the effects of friction along the scroll. Inasmuch as the design method leaves the cross-sectional shape undetermined, the effect of certain variations in sc… more
Date: October 1947
Creator: Brown, W. Byron & Bradshaw, Guy R.
Item Type: Refine your search to only Report
open access

Determination of elastic stresses in gas-turbine disks

Description: A method is presented for the calculation of elastic stresses in symmetrical disks typical of those of a high-temperature gas turbine. The method is essentially a finite-difference solution of the equilibrium and compatibility equations for elastic stresses in a symmetrical disk. Account can be taken of point-to-point variations in disk thickness, in temperature, in elastic modulus, in coefficient of thermal expansion, in material density, and in Poisson's ratio. No numerical integration or tri… more
Date: 1947
Creator: Manson, S. S.
Item Type: Refine your search to only Report
open access

Dislocation Theory of the Fatigue of Metals

Description: "A dislocation theory of fatigue failure for annealed solid solutions is presented. On the basis of this theory, an equation giving the dependence of the number of cycles for failure on the stress, the temperature, the material parameters, and the frequency is derived for uniformly stressed specimens. The equation is in quantitative agreement with the data" (p. 183).
Date: September 12, 1947
Creator: Machlin, E. S.
Item Type: Refine your search to only Report
open access

Effect of afterbody length and keel angle on minimum depth of step for landing stability and on take-off stability of a flying boat

Description: From Summary: "Tests were made to fill partly the need for information on the effect of afterbody dimensions on the hydrodynamic stability of a flying boat in smooth water. The dimensions investigated were depth of step, angle of afterbody keel, and length of afterbody. An analysis of the data showed that as either the afterbody length or keel angle was increased an accompanying increase in depth of step was required in order to maintain adequate landing stability."
Date: November 13, 1947
Creator: Olson, Roland E. & Land, Norman S.
Item Type: Refine your search to only Report
open access

Effect of combustor-inlet conditions on performance of an annular turbojet combustor

Description: From Summary: "The combustion performance, and particularly the phenomenon of altitude operational limits, was studied by operating the annular combustor of a turbojet engine over a range of conditions of air flow, inlet pressure, inlet temperature, and fuel flow. Information was obtained on the combustion efficiencies, the effect on combustion of inlet variables, the altitude operational limits with two different fuels, the pressure losses in the combustor, the temperature and velocity profile… more
Date: March 21, 1947
Creator: Childs, J. Howard; McCafferty, Richard J. & Surine, Oakley W.
Item Type: Refine your search to only Report
open access

Effect of Screens in Wide-Angle Diffusers

Description: "An experimental investigation at low airspeeds was made of the filling effect observed when a screen or similar resistance is placed across a diffuser. The filling effect is found to be real in that screens can prevent separation or restore separated flow in diffusers even of extreme divergence and to depend principally on screen location and pressure-drop coefficient of the screen. Results are given for three different diffusers of circular cross section with a variety of screen arrangements.… more
Date: June 26, 1947
Creator: Schubauer, G. B. & Spangenberg, W. G.
Item Type: Refine your search to only Report
open access

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.
Item Type: Refine your search to only Report
open access

Effects of temperature distribution and elastic properties of materials on gas-turbine-disk stresses

Description: From Summary: "Calculations were made to determine the influence of changes in temperature distribution and in elastic material properties on calculated elastic stresses for a typical gas-turbine disk. Severe temperature gradients caused thermal stresses of sufficient magnitude to reduce the operating safety of the disk. Small temperature gradients were found to be desirable because they produced thermal stresses that subtracted from the centrifugal stresses in the region of the rim."
Date: March 29, 1947
Creator: Holms, Arthur G. & Faldetta, Richard D.
Item Type: Refine your search to only Report
open access

Experimental investigation of the effects of viscosity on the drag and base pressure of bodies of revolution at a Mach number 1.5

Description: Models were tested to evaluate effects of Reynolds number for both laminar and turbulent boundary layers. Principal geometric variables investigated were afterbody shape and length-diameter ratio. Force tests and base-pressure measurements were made. Schlieren photographs were used to analyze the effects of viscosity on flow separation and shock-wave configuration and to verify the condition of the boundary layer as deduced from the force tests. The results are discussed and compared with theor… more
Date: January 31, 1947
Creator: Chapman, Dean R. & Perkins, Edward W.
Item Type: Refine your search to only Report
open access

Flight Investigation on a Fighter-Type Airplane of Factors Which Affect the Loads and Load Distributions on the Vertical Tail Surfaces During Rudder Kicks and Fishtails

Description: "Results are presented of a flight investigation conducted on a fighter-type airplane to determine the factors which affect the loads and load distributions on the vertical tail surfaces in maneuvers. An analysis is made of the data obtained in steady flight, rudder kicks, and fishtail maneuvers. For the rudder kicks, the significant loads were the "deflection load" resulting from an abrupt control deflection and the "dynamic load" consisting of a load corresponding to the new static equilibriu… more
Date: 1947
Creator: Boshar, John
Item Type: Refine your search to only Report
open access

Frequency-Response Method for Determination of Dynamic Stability Characteristics of Airplanes With Automatic Controls

Description: "A frequency-response method for determining the critical control-gearing and hunting oscillations of airplanes with automatic pilots is presented. The method is graphical and has several advantages over the standard numerical procedure based on Routh's discriminant. The chief advantage of the method is that direct use can be made of the measured response characteristics of the automatic pilot. This feature is especially useful in determining the existence, amplitude, and frequency of the hunti… more
Date: 1947
Creator: Greenberg, Harry
Item Type: Refine your search to only Report
open access

Further experiments on the flow and heat transfer in a heated turbulent air jet

Description: "Measurements have been made of the mean-total-head and mean-temperature fields in a round turbulent jet with various initial temperatures. The results show that the jet spreads more rapidly as its density becomes lower than that of the receiving medium, even when the difference is not sufficiently great to cause dynamic-pressure function. Rough analytical considerations have given the same relative spread. The effective "turbulent Prandtl number" for a section of the fully developed jet was fo… more
Date: August 18, 1947
Creator: Corrsin, Stanley & Uberoi, Mahinder S.
Item Type: Refine your search to only Report
open access

A General Small-Deflection Theory for Flat Sandwich Plates

Description: "A small-deflection theory is developed for the elastic behavior of orthotropic flat plates in which deflections due to shear are taken into account. In this theory, which covers all types of flat sandwich construction, a plate is characterized by seven physical constants (five stiffnesses and two Poisson ratios) of which six are independent. Both the energy expression and the differential equations are developed. Boundary conditions corresponding to simply supported, clamped, and elastically r… more
Date: September 30, 1947
Creator: Libove, Charles & Batdorf, S. B.
Item Type: Refine your search to only Report
open access

Hydrodynamic impact of a system with a single elastic mode I : theory and generalized solution with an application to an elastic airframe

Description: Solutions of impact of a rigid prismatic float connected by a massless spring to a rigid upper mass are presented. The solutions are based on hydrodynamic theory which has been experimentally confirmed for a rigid structure. Equations are given for defining the spring constant and the ratio of the sprung mass to the lower mass so that the two-mass system provides representation of the fundamental mode of an airplane wing. The forces calculated are more accurate than the forces which would be pr… more
Date: March 17, 1947
Creator: Mayo, Wilbur L.
Item Type: Refine your search to only Report
open access

The interdependence of various types of autoignition and knock

Description: A study of the relations existing among pin-point autoignition, homogeneous autoignition, and knock has been made by means of the NACA high-speed camera and the full-view combustion apparatus. High-speed photographic records of combustion, together with corresponding pressure-time traces, of benzene, 2,2,3-trimethylbutane, S-4, and M-4 fuels at various engine conditions have shown the engine conditions under which each of these phenomena occur and the relation of these phenomena to one another.
Date: February 10, 1947
Creator: Olsen, H. Lowell & Miller, Cearcy D.
Item Type: Refine your search to only Report
open access

Interference Method for Obtaining the Potential Flow Past an Arbitrary Cascade of Airfoils

Description: "A procedure is presented for obtaining the pressure distribution on an arbitrary airfoil section in cascade in a two-dimensional, incompressible, and nonviscous flow. The method considers directly the influence on a given airfoil of the rest of the cascade and evaluates this interference by an iterative process, which appeared to converge rapidly in the cases tried (about unit solidity, stagger angles of 0 degree and 45 degrees). Two variations of the basic interference calculations are descri… more
Date: January 10, 1947
Creator: Katzoff, S.; Finn, Robert S. & Laurence, James C.
Item Type: Refine your search to only Report
open access

Investigation in the Langley 19-foot pressure tunnel of two wings of NACA 65-210 and 64-210 airfoil sections with various type flaps

Description: Report presents the results of an investigation conducted in the Langley 19-foot pressure tunnel to determine the maximum lift and stalling characteristics of two thin wings equipped with several types of flaps. Split, single slotted, and double slotted flaps were tested on one wing which had NACA 65-210 airfoil sections and split and double slotted flaps were tested on the other, which had NACA 64-210 airfoil sections. Both wings were zero sweep, an aspect ratio of 9, and a taper ratio of 0.4.
Date: August 19, 1947
Creator: Sivells, James C. & Spooner, Stanley H.
Item Type: Refine your search to only Report
open access

Isolated and Cascade Airfoils With Prescribed Velocity Distribution

Description: "An exact solution of the problem of designing an airfoil with a prescribed velocity distribution on the suction surface in a given uniform flow of an incompressible perfect fluid is obtained by replacing the boundary of the airfoil by vortices. By this device, a method of solution is developed that is applicable both to isolated airfoils and to airfoils in cascade. The conformal transformation of the designed airfoil into a circle can then be obtained and the velocity distribution at any angle… more
Date: 1947
Creator: Goldstein, Arthur W. & Jerison, Meyer
Item Type: Refine your search to only Report
open access

On Similarity Rules for Transonic Flows

Description: "A method used by Tsien to derive similarity rules for hypersonic flows is utilized to derive Von Karman's similarity rules for transonic flows. At the lower limit of the transonic region of flow the theory yields a formula for the critical stream Mach numbers of a given family of symmetrical profiles. It is further shown that this formula can also be obtained by means of the Prandtl-Glauert small-perturbation method" (p. 83).
Date: December 9, 1947
Creator: Kaplan, Carl
Item Type: Refine your search to only Report
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