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Two-Phase Flow Through Apertures

Description: No Description Available.
Date: January 1, 0196
Creator: Isbin, H. S.
Partner: UNT Libraries Government Documents Department
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A New Form of Standard Resistance

Description: Report issued by the Bureau of Standards over new developments of electrical resistivity in manganin wire coils. The results of the developments are discussed. This report includes tables, illustrations, and photographs.
Date: October 1, 1908
Creator: Rosa, Edward B.
Partner: UNT Libraries Government Documents Department
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Damping Coefficients Due to Tail Surfaces in Aircraft

Description: "The object of the investigation described in this report was to compare the damping coefficients of an airfoil as calculated from a knowledge of the static characteristics of the section with those obtained experimentally with an oscillation. The damping coefficients as obtained, according to the conventional notation, can be considered either as due to pitching or as due to yawing, the oscillation in these experiments being so arranged that the surfaces oscillate about a vertical axis. This is in reality the case when the influence is yawing about the standard Z-axis, but it can also be considered as a pitching motion when the model is so rigged that its standard Y-axis becomes vertical" (p. 118).
Date: January 1, 1923
Creator: Chu, Lynn
Partner: UNT Libraries Government Documents Department
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Use of Sulphite Cellulose Extract as a Tanning Material

Description: Report issued by the Bureau of Standards over chemicals used for tanning leather hides. As stated in the introduction: "an investigation was conducted to determine the suitability of sulfite cellulose extracts, derived from the waste liquors discharged from paper pulp mills, for use in tanning hides for the manufacture of leather" (p. 309). This report includes tables, and photographs.
Date: November 1, 1926
Creator: Wallace, E. L. & Bowker, Roy Clement
Partner: UNT Libraries Government Documents Department
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Aircraft Woods: Their Properties, Selection, and Characteristics

Description: From Summary: "This report presents, further, information on the properties of various other native species of wood compared with spruce, and discusses the characteristics of a considerable number of them from the standpoint of their possible application in aircraft manufacture to supplement the woods that are now most commonly used."
Date: January 1, 1930
Creator: Markwardt, L. J.
Partner: UNT Libraries Government Documents Department
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A Method of Calculating the Ultimate Strength of Continuous Beams

Description: The purpose of this study was to investigate the strength of continuous beams after the elastic limit has been passed. As a result, a method of calculation, which is applicable to maximum load conditions, has been developed. The method is simpler than the methods now in use and it applies properly to conditions where the present methods fail to apply.
Date: February 1, 1930
Creator: Newlin, J. A. & Trayer, George W.
Partner: UNT Libraries Government Documents Department
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Pressure distribution over the fuselage of a PW-9 pursuit airplane in flight

Description: "This report presents the results obtained from pressure distribution tests on the fuselage of a PW-9 pursuit airplane in a number of conditions of flight. The investigation was made to determine the contribution of the fuselage to the total lift in conditions considered critical for the wing structure, and also to determine whether the fuselage loads acting simultaneously with the maximum tail loads were of such a character as to be of concern with respect to the structural design of other parts of the airplane. The results show that the contribution of the fuselage toward the total lift is small on this airplane" (p. 327).
Date: August 1, 1930
Creator: Rhode, Richard V. & Lundquist, Eugene E.
Partner: UNT Libraries Government Documents Department
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Flame Movement and Pressure Development in an Engine Cylinder

Description: "This investigation describes a visual method for making stroboscopic observations, through a large number of small windows, of the spread of flame throughout the combustion chamber of a gasoline engine. Data, secured by this method on a small engine burning gaseous fuels, are given to show the effects of mixture ratio, spark advance, engine speed, charge density, degree of dilution, compression ratio, and fuel composition on flame movement in the cylinder. Partial indicator diagrams showing pressure development during the combustion period are included" (p. 697).
Date: May 1, 1931
Creator: Marvin, Charles F., Jr. & Best, Robert D.
Partner: UNT Libraries Government Documents Department
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Air flow in a separating laminar boundary layer

Description: Report discussing the speed distribution in a laminar boundary layer on the surface of an elliptic cylinder, of major and minor axes 11.78 and 3.98 inches, respectively, has been determined by means of a hot-wire anemometer. The direction of the impinging air stream was parallel to the major axis. Special attention was given to the region of separation and to the exact location of the point of separation. An approximate method, developed by K. Pohlhausen for computing the speed distribution, the thickness of the layer, and the point of separation, is described in detail; and speed-distribution curves calculated by this method are presented for comparison with experiment.
Date: December 1, 1934
Creator: Schubauer, G. B.
Partner: UNT Libraries Government Documents Department
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Characteristics of the NACA 23012 airfoil from tests in the full-scale and variable-density tunnels

Description: "This report gives the results of tests in the NACA full-scale and variable-density tunnels of a new wing section, the NACA 23012, which is one of the more promising of an extended series of related airfoils recently developed. The tests were made at several values of the Reynolds number between 1,000,000 and 8,000,000. The new airfoil develops a reasonably high maximum lift and a low profile drag, which results in an unusually high value of the speed-range index. In addition, the pitching-moment coefficient is very small" (p. 435).
Date: March 1, 1935
Creator: Jacobs, Eastman N. & Clay, William C.
Partner: UNT Libraries Government Documents Department
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General Airplane Performance

Description: "Equations have been developed for the analysis of the performance of the ideal airplane, leading to an approximate physical interpretation of the performance problem. The basic sea-level airplane parameters have been generalized to altitude parameters and a new parameter has been introduced and physically interpreted. The performance analysis for actual airplanes has been obtained in terms of the equivalent ideal airplane in order that the charts developed for use in practical calculations will for the most part apply to any type of engine-propeller combination and system of control, the only additional material required consisting of the actual engine and propeller curves for propulsion unit" (p. 241).
Date: June 1, 1937
Creator: Rockfeller, W. C.
Partner: UNT Libraries Government Documents Department
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Model Study of Channel Improvement and Stabilization in the Pryors Island Reach of the Ohio River

Description: This technical memorandum constitutes a complete report on a model study of the Pryors Island reach of the Ohio River, made for the purpose of determining the most effective plan of regulating works for the further improvement and stabilization of the navigable channel.
Date: September 1, 1938
Creator: Waterways Experiment Station (U.S.)
Partner: UNT Libraries Government Documents Department
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The Precipitation of Uranium Peroxide in the Presence of Fluorides

Description: The large-scale recovery of uranium from materials which also contained great quantities of fluorides did not give a product which had a low enough fluoride content to be treated satisfactorily by the other extraction process. The objective of the investigations carried out in this laboratory was a method of reducing the amount of fluoride which accompanied the uranium. The material from which the uranium was recovered in the industrial process was a slag containing (in addition to uranium) magnesium fluoride, calcium and dolomitic lines, crucible dross, and other waste products from the reaction of magnesium metal and uranium hexafluoride. Most of the fluoride was removed from this mixture by heating the roasted and ground slag with sulfuric acid. The residue was mixed with water and much of the caclium sulfate and fluoride, magnesium fluoride, and hydrated ferric oxide and alumina was precipitated by reducing the acidity. After filtering off the precipitate, ammonium sulfate was added to the solution and uranium peroxide (UO{sub 4} {center_dot} 2H{sub 2}O) was precipitated by addition of hydrogen peroxide. The pH of the solution was maintained between 3.0 and 3.5 during the precipitation by addition of sodium hydroxide. The uranium peroxide, even after washing, contained between 2 and 3% fluoride. The percentage of fluoride could be reduced to 0.5% by precipitating the peroxide from a more acidic solution but this required the use of much larger amounts of hydrogen peroxide.
Date: January 1, 1941
Creator: King, Edward J.
Partner: UNT Libraries Government Documents Department
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