Technical Report Archive & Image Library (TRAIL) - 32,562 Matching Results

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The Effect of a 4-Percent-High Spoiler on Buffeting Forces on a NACA 65(Sub 06)A004 Two-Dimensional Airfoil at Subsonic Mach Numbers

Description: Memorandum presenting testing of an NACA 65(sub 06)A004 airfoil to determine the effects of a solid-strip spoiler on buffeting forces. Fluctuations of both section normal-force coefficient and of section pitching-moment coefficient are presented as functions of angle of attack and of section normal-force coefficient. Generally, the spoiler decreased the fluctuating section normal-force and pitching-moment coefficients if comparison is made at constant angle of attack and increased these coeffic… more
Date: March 23, 1955
Creator: Mellenthin, Jack A.
Partner: UNT Libraries Government Documents Department
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The Flow About a Section of a Finite-Aspect-Ratio NACA 0018 Airfoil on a Transonic Bump

Description: Note presenting pressure distributions on a semispan rectangular wing model with an NACA 0015 airfoil section and a moderate aspect ratio at one spanwise station in tests made on a transonic bump in the 16-foot high-speed wind tunnel. The results indicated that at a fixed angle of attack, a region developed over the airfoil wherein the Mach number at each point remained essentially constant as the free-stream Mach number was increased above the critical.
Date: October 1953
Creator: Mellenthin, Jack A.
Partner: UNT Libraries Government Documents Department
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Some Observations on Stress-Corrosion Cracking of Single Crystals of AZ61X Magnesium Alloy

Description: Note presenting exploratory tests of the stress-corrosion cracking of single crystals of solution-treated AZ61X magnesium alloy in distilled water, in hydrofluoric acid, and in a salt-chromate solution. The results of this paper show that failures often start and run on planes other than the basal plane and are inconsistent with previously generated hypotheses. Results regarding the pilot tests on polycrystalline specimens and single-crystal tests are provided.
Date: July 1957
Creator: Meller, F. & Metzger, M.
Partner: UNT Libraries Government Documents Department
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Contribution to the Theory of Tail-Wheel Shimmy

Description: A basic theoretical and experimental investigation is made of the shimmy behavior of a swiveling landing gear, the experimental tests being conducted with a small wheel mounted over a continuous belt. Effects of wheel loading, rolling velocity, rearward position of the wheel with respect to the swivel axis, tire elasticity, and torsional flexibility of the fuselage are investigated both experimentally and theoretically. A major theoretical conclusion is that the motion of a landing gear moving … more
Date: December 1954
Creator: Melzer, M.
Partner: UNT Libraries Government Documents Department
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Aerodynamic Design of Axial-Flow Compressors: Volume 1

Description: Compendium presenting a comprehensive integration of available aerodynamic design information on axial-flow compressors. The subjects of the first volume of this investigation are objectives and scope, compressor design requirements, compressor design system, potential flow in two-dimensional cascades, and viscous flow in two-dimensional cascades.
Date: August 1, 1956
Creator: Members of the Compressor and Turbine Research Division
Partner: UNT Libraries Government Documents Department
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Aerodynamic Design of Axial-Flow Compressors, Volume 2

Description: "Available experimental two-dimensional-cascade data for conventional compressor blade sections are correlated. The two-dimensional cascade and some of the principal aerodynamic factors involved in its operation are first briefly described. Then the data are analyzed by examining the variation of cascade performance at a reference incidence angle in the region of minimum loss" (p. 1).
Date: August 1, 1956
Creator: Members of the Compressor and Turbine Research Division
Partner: UNT Libraries Government Documents Department
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Reactor Engineering Division Quarterly Report [for] October, November, December 1955. Section I

Description: The gastight steel building (400,000 cu ft) in which all radioactive components are to be housed has been completed by the Graver Tank Company. This structure was tested for strength at 18.75 psig (20% above design pressure) and then tested for leaks. No leaks were found in soap bubble testing of all welded seams. Continuous measurements of temperature and pressure over a ten-day period showed the leakage, if any, to be less than the 500 cu/ ft/day at 15 psig specified. The gastight cylinder wa… more
Date: April 1956
Creator: Members of the Reactor Engineering Division
Partner: UNT Libraries Government Documents Department
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Reactor Engineering Division Quarterly Report Section I January, February, March. 1956

Description: Physical calculations have been performed for various combinations of the four types of fuel assemblies to be used in the EBWR core. Two thicknesses of plates (0.205 in. and 0.274 in., including two 0.020-in. cladding layers) are to be made of both natural uranium and uranium containing 1.44% U235. Any given fuel assembly contains six identical plates. A total of 148 assemblies, 74 natural and 74 enriched, are to be fabricated. Various configurations of these fuel assemblies can be used to (1) … more
Date: July 1956
Creator: Members of the Reactor Engineering Division
Partner: UNT Libraries Government Documents Department
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Reactor Engineering Division Semiannual Report December 1, 1951 through May 31, 1952

Description: This report describes the construction of a reactor and the research conducted in the reactor such as solid fuel and liquid fuel research, boiling reactor experiments, CP-6 bond testing program, and water quality control experiments for CP-6 program.
Date: June 15, 1952
Creator: Members of the Reactor Engineering Division
Partner: UNT Libraries Government Documents Department
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Habitat Development Field Investigations, Windmill Point Marsh Development Site, James River, Virginia: Appendix D

Description: Appendix containing calculations of the mass transport of chemical components and the error terms used to accompany the second volume of a report on the environmental impacts of marsh development with dredged material as part of a study on the feasibility of marsh development using dredged material at the Windmill Point Marsh Development Site, James River, Virginia.
Date: August 1978
Creator: Menchhoff, Jerry A.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of the Boundary Layer and Wake and Their Relation to Airfoil Characteristics - NACA 65(Sub 1)-012 Airfoil With a True Contour Flap and a Beveled-Trailing-Edge Flap

Description: Note presenting two-dimensional flow tests conduced in the 2.5-by 6-foot test section of the stability tunnel on an NACA 65(sub 1)-012 airfoil with a true contour flap and a beveled-trailing-edge flap to determine lift, drag, hinge moment, boundary layer, and wake characteristics. Measurements indicated that the static-pressure gradient through a boundary layer may be large in regions where the airfoil has a small radius of curvature and that a static-pressure rise exists at the vertical positi… more
Date: June 1947
Creator: Mendelsohn, Robert A.
Partner: UNT Libraries Government Documents Department
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Comparison between the measured and theoretical span loadings on a moderately swept-forward and a moderately swept-back semispan wing

Description: Report presenting an investigation in the stability tunnel on two semispan swept-wing models to determine experimentally the span-load distributions and to compare the experimental and theoretical results. Lift, drag, pitching moment, and stalling characteristics are provided.
Date: July 1947
Creator: Mendelsohn, Robert A. & Brewer, Jack D.
Partner: UNT Libraries Government Documents Department
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Effect of the tunnel-wall boundary layer on test results of a wing protruding from a tunnel wall

Description: Report presenting two-dimensional span-loading tests of a two-foot-chord NACA 65(sub 1)-012 airfoil model in the stability tunnel to determine tunnel-wall boundary-layer effects. Testing indicated that a small loss in average load may be expected. Results regarding tunnel-wall velocity profiles, pressure distributions, spanwise surveys, and force and moment coefficients are provided.
Date: April 1947
Creator: Mendelsohn, Robert A. & Polhamus, Josephine F.
Partner: UNT Libraries Government Documents Department
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Practical solution of plastic deformation problems in elastic-plastic range

Description: A practical method for solving plastic deformation problems in the elastic-plastic range is presented. The method is one of successive approximations and is illustrated by four examples which include a flat plate with temperature distribution across the width, a thin shell with axial temperature distribution, a solid cylinder with radial temperature distribution, and a rotating disk with radial temperature distribution.
Date: September 1957
Creator: Mendelson, A. & Manson, S. S.
Partner: UNT Libraries Government Documents Department
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Calculated Performance of a Compression-Ignition Engine-Compressor-Turbine Combination Based on Experimental Data

Description: Note presenting calculations based on test data taken on a single-cylinder compression-ignition engine with a compression ratio of 13.1 and an engine speed of 2200 rpm to determine the performance at sea-level conditions of a compression-ignition engine geared together with a compressor and a turbine. The net specific power output increased with decreasing compression ratio and with increasing fuel-air ratio and engine speed.
Date: December 1948
Creator: Mendelson, Alexander
Partner: UNT Libraries Government Documents Department
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Effect of Aerodynamic Hysteresis on Critical Flutter Speed at Stall

Description: Memorandum presenting a theoretical analysis of the effect of aerodynamic hysteresis on stalling flutter. The results were applied to a given airfoil and correlation of the experimental and theoretical results was found possible by assuming that the angle of aerodynamic lag varies as the slope of the static-lift curve. It was shown that the phenomenon of stalling flutter can at least in some cases be explained on the basis of an aerodynamic lag or hysteresis effect.
Date: June 18, 1948
Creator: Mendelson, Alexander
Partner: UNT Libraries Government Documents Department
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Effect of Centrifugal Force on Critical Flutter Speed on a Uniform Cantilever Beam

Description: Report presenting theoretical calculations made by means of semirigid-flutter theory to determine the effect of centrifugal force on the critical flutter speed of a uniform cantilever beam. Calculations are made on airfoils with fundamental bending frequencies up to 2000 radian per second. Centrifugal force can under certain conditions reduce the critical flutter speed.
Date: June 18, 1948
Creator: Mendelson, Alexander
Partner: UNT Libraries Government Documents Department
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Lift and Moment Equations for Oscillating Airfoils in an Infinite Unstaggered Cascade

Description: Aerodynamic coefficients similar to those of the isolated airfoil are obtained as functions of the cascade geometry and the phasing between successive blades; the phasings considered are zero, 90 degrees, and 180 degrees. These aerodynamic coefficients are plotted for the special case when all the airfoils are vibrating in bending in phase (360 degree phasing). It is shown that the effect of cascading for this case is to reduce greatly the aerodynamic damping.
Date: October 1954
Creator: Mendelson, Alexander & Carroll, Robert W.
Partner: UNT Libraries Government Documents Department
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Analytical determination of coupled bending-torsion vibrations of cantilever beams by means of station functions

Description: From Summary: "A method based on the concept of Station Functions is presented for calculating the modes and the frequencies of nonuniform cantilever beams vibrating in torsion, bending, and coupled bending-torsion motion. The method combines some of the advantages of the Rayleigh-Ritz and Stodola methods, in that a continuous loading function for the beam is used, with the advantages of the influence-coefficient method, in that the continuous loading function is obtained in terms of the displa… more
Date: 1951
Creator: Mendelson, Alexander & Gendler, Selwyn
Partner: UNT Libraries Government Documents Department
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Analysis of elastic thermal stresses in thin plate with spanwise and chordwise variations of temperature and thickness

Description: From Introduction: "The object of the present paper is to present an approximate method for calculating accurately the thermal stresses in a thin plate with both chordwise and spanwise variations in temperature and chordwise but restricted spanwise variations in thickness."
Date: November 1956
Creator: Mendelson, Alexander & Hirschberg, Marvin
Partner: UNT Libraries Government Documents Department
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Shorter Contributions to General Geology, 1928

Description: From introduction: The district discussed in this report embraces the entire northern peninsula of Michigan and the parts of northern Wisconsin and northeastern Minnesota that were covered by a re-advance of the Superior lobe of the Labrador ice sheet late in the Wisconsin stage of glaciation.
Date: 1929
Creator: Mendenhall, W. C.
Partner: UNT Libraries Government Documents Department
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Shorter Contributions to General Geology, 1929

Description: From introduction: This report describes the deposits of analcite in the Green River formation, to compare them with other similar deposits, and to present them with other similar deposits, and to present the observations and inferences that led him to explain them as alteration products of volcanic ash that fell into an ancient saline lake. The report also records the occurrence of several thin beds of sepiolite, or meerschaum, in the Green River formation and presents new data on the molds of… more
Date: 1930
Creator: Mendenhall, W. C.
Partner: UNT Libraries Government Documents Department
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