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Special Studies in Electrolysis Mitigation: 4. A Preliminary Report on Electrolysis Mitigation in Elyria, Ohio, with Recommendations for Mitigation
Technical paper issued by the Bureau of Standards over surveys conducted on the electrical conditions of railway tracks in Elyria, Ohio. The results of the surveys are presented and discussed. This paper includes tables, maps, and illustrations.
Date:
January 22, 1916
Creator:
McCollum, Burton & Logan, K. H.
Object Type:
Report
System:
The UNT Digital Library
An Apparatus for Measuring the Relative Wear of Sole Leathers, and the Results Obtained with Leather from Different Parts of a Hide
Technical paper issued by the Bureau of Standards over studies conducted on the quality of sole leather. As stated in the introduction, "the development of a simple method for quickly determining the durability of sole leather seemed desirable, and this paper discusses a laboratory apparatus designed for this purpose and also presents the results of tests made to date to determine the relative wear of leather from different parts of the hide" (p. 3). This paper includes illustrations, and photographs.
Date:
November 22, 1919
Creator:
Hart, R. W. & Bowker, R. C.
Object Type:
Report
System:
The UNT Digital Library
Radio-Frequency Resistance and Inductance of Coils Used in Broadcast Reception
Technical paper issued by the Bureau of Standards over radio-frequency resistance in radio reception. As stated in the introduction, "the purpose of this paper is to present data on the radio-frequency resistance and inductance of coils within the range of frequencies used in radiotelephone broadcasting" (p. 651). This paper includes tables, and illustrations.
Date:
October 22, 1925
Creator:
Hund, August & De Groot, H. B.
Object Type:
Report
System:
The UNT Digital Library
Water-pressure distribution on seaplane float
The investigation presented in this report was conducted for the purpose of determining the distribution and magnitude of water pressures likely to be experienced on seaplane hulls in service. It consisted of the development and construction of apparatus for recording water pressures lasting one one-hundredth second or longer and of flight tests to determine the water pressures on a UO-1 seaplane float under various conditions of taxiing, taking off, and landing. The apparatus developed was found to operate with satisfactory accuracy and is suitable for flight tests on other seaplanes. The tests on the UO-1 showed that maximum pressures of about 6.5 pounds per square inch occur at the step for the full width of the float bottom. Proceeding forward from the step the maximum pressures decrease in magnitude uniformly toward the bow, and the region of highest pressures narrows toward the keel. Immediately abaft the step the maximum pressures are very small, but increase in magnitude toward the stern and there once reached a value of about 5 pounds per square inch. (author).
Date:
December 22, 1927
Creator:
Thompson, F. L.
Object Type:
Report
System:
The UNT Digital Library
The 7 by 10 Foot Wind Tunnel of the National Advisory Committee for Aeronautics
This report presents a description of the 7 by 10 foot wind tunnel and associated apparatus of the National Advisory Committee for Aeronautics. Included also are calibration test results and characteristic test data of both static force tests and autorotation tests made in the tunnel.
Date:
October 22, 1931
Creator:
Harris, Thomas A.
Object Type:
Report
System:
The UNT Digital Library
Flight tests of the drag and torque of the propeller in terminal-velocity dives
From Summary: "The drag and torque of a controllable propeller at various blade-angle settings, and under various diving conditions, were measured by indirect method on F6C-4 airplane in flight. The object of these tests were (1) to provide data on which calculations of the terminal velocity with a throttled engine and the accompanying engine speed could be based and (2) to determine the possibility of utilizing the propeller as an air brake to reduce the terminal velocity. The data obtained were used in the establishment of propeller charts, on the basis of which the terminal velocity and engine speed could be calculated for airplanes whose characteristics fall within the range of these tests."
Date:
August 22, 1933
Creator:
Rhode, Richard V. & Pearson, Henry A.
Object Type:
Report
System:
The UNT Digital Library
On the Theory of Laminar Boundary Layers Involving Separation
"This paper presents a mathematical discussion of the laminar boundary layer, which was developed with a view of facilitating the investigation of those boundary layers in particular for which the phenomenon of separation occurs. The treatment starts with a slight modification of the form of the boundary layer equation first published by Von Mises. Two approximate solutions of this equation are found, one of which is exact at the outer edge of the boundary layer while the other is exact at the wall" (p. 541).
Date:
May 22, 1934
Creator:
von Karman, T. & Millikan, C. B.
Object Type:
Report
System:
The UNT Digital Library
The effect of turbulence on the drag of flat plates
"In determining the effect of turbulence on the forces exerted on bodies in the air stream of a wind tunnel, it is commonly assumed that the indications of the standard Pitot-static tube used to determine the air speed are not dependent on the turbulence. To investigate the truth of this assumption, the drag of a normally exposed flat plate, the difference in pressure between the front and rear of a thin circular disk, the rate of rotation of a vane anemometer, and the pressure developed by a standard Pitot-static tube were measured in an air stream for several conditions of turbulence. The results may be interpreted as indicating that there is no appreciable effect of turbulence on the vane anemometer and the standard pitot-static tube, but that there is small effect on the drag of a flat plate and the pressure difference between front and rear of a disk" (p. 129).
Date:
June 22, 1935
Creator:
Schubauer, G. B. & Dryden, H. L.
Object Type:
Report
System:
The UNT Digital Library
Aircraft Accidents: Methods of Analysis
This report is a revision of NACA-TR-357. It was prepared by the Committee on Aircraft Accidents. The purpose of this report is to provide a basis for the classification and comparison of aircraft accidents, both civil and military.
Date:
June 22, 1936
Creator:
Committee on Aircraft Accidents
Object Type:
Report
System:
The UNT Digital Library
Mechanism of flutter: A theoretical and experimental investigation of the flutter problem
From Summary: "The results of the basic flutter theory originally devised in 1934 and published as NACA Technical Report no. 496 are presented in a simpler and more complete form convenient for further studies. The paper attempts to facilitate the judgement of flutter problems by a systematic survey of the theoretical effects of the various parameters. A large number of experiments were conducted on cantilever wings, with and without ailerons, in the NACA high-speed wind tunnel for the purpose of verifying the theory and to study its adaptability to three-dimensional problems."
Date:
September 22, 1938
Creator:
Theodorsen, Theodore & Garrick, I. E.
Object Type:
Report
System:
The UNT Digital Library
Tensile Elastic Properties of 18:8 Chromium-Nickel Steel as Affected by Plastic Deformation
"The relationship between stress and strain, and between stress and permanent set, for 18:8 alloy as affected by prior plastic deformation is discussed. Hysteresis and creep and their effects on the stress-strain and stress-set curves are also considered, as well as the influence of duration of the rest interval after cold work and the influence of plastic deformation on proof stresses, on the modulus of elasticity at zero stress, and on the curvature of the stress-strain line. A constant (c sub 1) is suggested to represent the variation of the modulus of elasticity with stress" (p. 539).
Date:
November 22, 1938
Creator:
McAdam, D. J., Jr. & Mebs, R. W.
Object Type:
Report
System:
The UNT Digital Library
An investigation of the drag of windshields in the 8-foot high-speed wind tunnel
Report presents the results of tests made to determine the drag of closed-cockpit and transport-type windshields. The tests were made at speeds corresponding to a Mach number range of approximately 0.25 to 0.58 in the NACA 8-foot high-speed wind tunnel. This speed range corresponds to a test Reynolds number range of 2,510,000 to 4,830,000 based on the mean aerodynamic chord of the full-span model (17.29 in.). The shapes of the windshield proper, the hood, and the tail fairing were systematically varied to include common types and refined design.
Date:
May 22, 1939
Creator:
Robinson, Russell G. & Delano, James B.
Object Type:
Report
System:
The UNT Digital Library
The problem of cooling an air-cooled cylinder on an aircraft engine
An analysis of the cooling problem has been to show by what means the cooling of an air-cooled aircraft engine may be improved. Each means of improving cooling is analyzed on the basis of effectiveness in cooling with respect to power for cooling. The altitude problem is analyzed for both supercharged and unsupercharged engines. The case of ground cooling is also discussed. The heat-transfer process from the hot gases to the cylinder wall is discussed on the basis of the fundamentals of heat transfer and thermodynamics. Adiabatic air-temperature rise at a stagnation point in compressible flow is shown to depend only on the velocity of flow.
Date:
April 22, 1940
Creator:
Brevoort, M. J. & Joyner, U. T.
Object Type:
Report
System:
The UNT Digital Library
Methods of analyzing wind-tunnel data for dynamic flight conditions
The effects of power on the stability and the control characteristics of an airplane are discussed and methods of analysis are given for evaluating certain dynamic characteristics of the airplane that are not directly discernible from wind tunnel tests alone. Data are presented to show how the characteristics of a model tested in a wind tunnel are affected by power. The response of an airplane to a rolling and a yawing disturbance is discussed, particularly in regard to changes in wing dihedral and fin area. Solutions of the lateral equations of motion are given in a form suitable for direct computations. An approximate formula is developed that permits the rapid estimation of the accelerations produced during pull-up maneuvers involving abrupt elevator deflections.
Date:
July 22, 1941
Creator:
Donlan, C. J. & Recant, I. G.
Object Type:
Report
System:
The UNT Digital Library
Test of single-stage axial-flow fan
"A single-stage axial fan was built and tested in the shop of the propeller-research tunnel of the NACA. The fan comprised a simple 24-blade rotor having a diameter of 21 inches and a solidity of 0.86 and a set of 37 contravanes having a solidity of 1.33. The rotor was driven by a 25-horsepower motor capable of rotating at a speed of 3600 r.p.m. The fan was tested for volume, pressure, and efficiency over a range of delivery pressures and volumes for a wide range of contravane and blade-angle settings" (p. 49).
Date:
September 22, 1941
Creator:
Bell, E. Barton
Object Type:
Report
System:
The UNT Digital Library
On Certain Phase Equilibria in the Ternary System Uranyl Nitrate--Ether--Water at 25° and at 1°C
This report follows a study that deals with a portion of the ternary diagram previously analyzed, namely the boundary curves which separate the central area of two coexistent liquid phases from the two border stripe representing one-phase liquid systems.
Date:
October 22, 1942
Creator:
Van Name, Ralph Gibbs
Object Type:
Report
System:
The UNT Digital Library
Effect of Temperature on the Resonance Absorption of Neutrons by Uranium
The resonance absorption of uranium for neutrons has been investigated between 20 degree C and 1000 degree C. Experiments were caried out on both UO2, density 4.63, and metal. The resonance activity was measured with respect to that of an iodine monitor at several different temperatures and the ratio of activity at temperature T to that at 20 degree C was determined. The increase in activity is 0.9 per cent per 100 degree C for the oxide and 1.1 percent per 100 degree C for the metal. The period of U239 was found to be 23.54 +- 0.05 min.
Date:
April 22, 1943
Creator:
Mitchell, Allan C. G. (Allan Charles Gray), 1902-; Slotin, Louis; Marshall, John; Nedzel, V. A.; Brown, L. J. & Pruett, John R.
Object Type:
Report
System:
The UNT Digital Library
Metallurgical Laboratory, Chemical Research - Analytical, Graphite Purity Research Program
Abstract. Chemical analytical studies of graphite raw materials have revealed new sources of petroleum cokes and pitches of greater purity than those previously used in the manufacture of project graphite. The use of these raw materials of exceptional purity has resulted in an improvement in k of the order of one per cent as compared with the AGOT-AGNT graphite typical of the previous production. A study of the graphitizing process has shown that no dangerous impurities are introduced in the graphite in manufacture; rather, the process actually purifies. furthermore, impurities are distributed homogeneously within the furnace charge; thus the AGOT-AGNT distinction is no longer necessary. A comparison of the methods of graphite testing has demonstrated excellent correlations between chemical analytical data, the results of the function test at Argonne, and the sigma pile experiments. It may therefore be inferred that chemical testing should be an adequate control of the graphite purity. Methods are described for the analysis of ash, B, V, TI, FE, and Ca in petroleum coke, pitch, and graphite.
Date:
December 22, 1943
Creator:
Boyd, G. E.; Curtis, R. E. & Johnston, W. H.
Object Type:
Report
System:
The UNT Digital Library
Investigation of the NACA 4-(3)(8)-045 Two-Blade Propellers at Forward Mach Numbers to 0.725 to Determine the Effects of Compressibility and Solidity on Performance
From Summary: "As part of a general investigation of propellers at high forward speeds, tests of two 2-blade propellers having the NACA 4-(3)(8)-03 and NACA 4-(3)(8)-45 blade designs have been made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 60 degrees for forward Mach numbers from 0.165 to 0.725 to establish in detail the changes in propeller characteristics due to compressibility effects. These propellers differed primarily only in blade solidity, one propeller having 50 percent and more solidity than the other. Serious losses in propeller efficiency were found as the propeller tip Mach number exceeded 0.91, irrespective of forward speed or blade angle."
Date:
January 22, 1944
Creator:
Stack, John; Draley, Eugene C.; Delano, James B. & Feldman, Lewis
Object Type:
Report
System:
The UNT Digital Library
Metallurgical Laboratory, Chemical Research - Radiation Chemistry, the Effect of Radiation on Water and Aqueous Solutions of Inorganic Substances
Technical report summarizing our knowledge of the chemical effects of ionizing radiation upon water and upon aqueous solutions of inorganic compounds. The types of radiation considered are beta rays, gamma and X rays, and heavy particles, notably neutrons, deuterons, alpha rays and fission recoils.
Date:
February 22, 1944
Creator:
Allen, A. O.
Object Type:
Report
System:
The UNT Digital Library
Biological Action of Gamma and X-Rays
Report of experimentation on mice of exposure to daily doses of gamma radiation at two rates and the resultant damage.
Date:
December 22, 1944
Creator:
Lorenz, E.; Eschenbrenner, A.; Derringer, M. & Heston, W. E.
Object Type:
Report
System:
The UNT Digital Library
The Digging-in of a Warped Rod Into a Rib
Abstract. Some rather idealized considerations are given regarding the depth a warped rod presses into the ribs at the places of contact. It appears that this distance may, under some conditions, be of the order of 70 times greater than for a straight rod resting uniformly on the ribs.
Date:
January 22, 1945
Creator:
Martin, A. V.
Object Type:
Report
System:
The UNT Digital Library
Quantitative Recovery of Tuballoy From Tuballoy Tetrafluoride
Report discussing various procedures for recovering tuballoy from tuballoy tetrafluoride, also called "green salt." Results from trial runs of each procedure are presented.
Date:
February 22, 1945
Creator:
Gates, J. W., Jr.; Andrews, L. J. & Schaap, Ward B.
Object Type:
Report
System:
The UNT Digital Library
The Spectrographic Analysis of Beryllium and its Compounds
Abstract. Spectrographic procedures for determining small amounts of the common contaminants in beryllium and its compounds are described. Suggestions relative to the preparation of synthetic standards are also given.
Date:
June 22, 1945
Creator:
Smith, A. Lee (Albert Lee), 1924-
Object Type:
Report
System:
The UNT Digital Library