Technical Report Archive & Image Library (TRAIL) - 1,438 Matching Results

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Application of the Theory of Free Jets

Description: Based upon Kirchoff's theory of free jets the flow through different screen arrangements of flat plates, as chiefly encountered with turbines in the cavitation zone is defined. It is shown by experiments that these theoretical results are very well representative in most cases of the conditions of discharge from water in air and consequently by cavitation. In addition, the experiments reveal a picture of the discrepancies between the actual flow and the theory of discharge of air in air (of wat… more
Date: April 1932
Creator: Betz, A. & Petersohn, E.
Partner: UNT Libraries Government Documents Department
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Applying the results of experiments on small models in the wind tunnel to the calculation of full-sized aircraft

Description: This report presents the attempt to develop a law which will permit the use of results obtained on small models in a tunnel for the calculation of full-sized airplanes, or if it exists, a law of similitude relating air forces on a full-sized plane to those on a reduced scale model.
Date: April 1922
Creator: Robert
Partner: UNT Libraries Government Documents Department
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Approximate Calculation of Multispar Cantilever and Semicantilever Wings With Parallel Ribs Under Direct and Indirect Loading

Description: A method is presented for approximate static calculation, which is based on the customary assumption of rigid ribs, while taking into account the systematic errors in the calculation results due to this arbitrary assumption. The procedure is given in greater detail for semicantilever and cantilever wings with polygonal spar plan form and for wings under direct loading only. The last example illustrates the advantages of the use of influence lines for such wing structures and their practical int… more
Date: August 1932
Creator: Sänger, Eugen
Partner: UNT Libraries Government Documents Department
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Approximate Calculation of the Static Longitudinal Stability of Airplanes

Description: It seems desirable to have some simple method for calculating quickly and with sufficient accuracy: 1) the correct position of the center of gravity; 2) the requisite tail-group dimensions; 3) and the course of the wing and tail-group moments. In out deductions, we will first replace the biplane (disregarding the effect of stagger, decalage and induced drag) by an equivalent monoplane, whose dimensions and position in space can be approximately determined in a simple manner.
Date: November 1926
Creator: Bienen, Theodor
Partner: UNT Libraries Government Documents Department
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An Approximate Method for Calculation of the Laminar Boundary Layer with Suction for Bodies of Arbitrary Shape

Description: From Summary: "Various ways were tried recently to decrease the friction drag of a body in a flow; they all employ influencing the boundary layer. One of them consists in keeping the boundary layer Laminar by suction; promising tests have been carried out. Since for large Reynolds numbers the friction drag of the laminar boundary layer is much lower than that of the turbulent boundary layer, a considerable saving in drag results from keeping the boundary layer laminar, even with the blower powe… more
Date: March 1949
Creator: Schlichting, H.
Partner: UNT Libraries Government Documents Department
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Approximation method for determining the static stability of a monoplane glider

Description: The calculations in this paper afford an approximate solution of the static stability. A derivation of the formulas for moment coefficient of a wing, moment coefficient of elevator, and the total moment of the combined wing and elevator and the moment coefficient with reference to the center of gravity are provided.
Date: November 1927
Creator: Lippisch, A.
Partner: UNT Libraries Government Documents Department
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The Art of Writing Scientific Reports

Description: As the purpose of the report is to transmit as smoothly and as easily as possible, certain facts and ideas, to the average person likely to read it, it should be written in a full and simple enough manner to be comprehended by the least tutored, and still not be boring to the more learned readers.
Date: March 1921
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department
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Atomization of Liquid Fuels Part 1: Relation Between Atomization and Combustion, Methods Employed for Determining the Size of Particles and Small Drops, Choice of Experimental Method

Description: In the present treatise we will consider chiefly the problem of solid injection in comparison with air injection. On leaving the valve or nozzle through one or more small openings, the fuel is split up into innumerable fine drops, which penetrate the combustion chamber in divergent directions in the form of a conical jet. The efficiency of this jet is judged from the following three viewpoints: 1) with respect to the fineness of atomization; 2) with respect to the direction or distribution of s… more
Date: September 1925
Creator: Kuehn
Partner: UNT Libraries Government Documents Department
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Atomization of Liquid Fuels Part 2: Description of Apparatus, Fuels Tested, Atomization Experiments, Discharge Measurements, Atomization

Description: This report describes the design and operation of a nozzle to inject fuel into an engine. The design of the nozzle is open, without any compulsory or automatic stop-valve. The fuel injection is regulated simply by the pressure and the adjustment of the fuel pump.
Date: September 1925
Creator: Kuehn, R.
Partner: UNT Libraries Government Documents Department
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Atomization of Liquid Fuels Part 3: Critical Discussion of Experimental Reesults, Mixing the Atomized Fuel with Air

Description: This report provides a critical discussion of the results of the experiments conducted in the previous NACA-TM's 329 and 330. The main object of this investigation was to determine the size of the drops in mechanical atomization.
Date: September 1925
Creator: Kuehn, R.
Partner: UNT Libraries Government Documents Department
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Attaining a Steady Air Stream in Wind Tunnels

Description: "Many experimental arrangements of varying kind involve the problems of assuring a large, steady air stream both as to volume and to time. For this reason a separate discussion of the methods by which this is achieved should prove of particular interest. Motors and blades receive special attention and a review of existent wind tunnels is also provided" (p. 1).
Date: October 1933
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department
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The "Autogiro"

Description: Report presenting a description of the autogiro, which is a flying machine built and designed in Spain. A history of the device and the reasons why it is safer and more stable than a typical aircraft are provided.
Date: July 1923
Creator: Moreno-Caracciolo, M.
Partner: UNT Libraries Government Documents Department
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Automatic Stability of Airplanes

Description: It is endeavored in this report to give a full outline of the problem of airplane stability and to classify the proposed solutions systematically. Longitudinal stability, which can be studied separately, is considered first. The combination of lateral and directional stabilities, which cannot be separated, will be dealt with later.
Date: December 1932
Creator: Haus
Partner: UNT Libraries Government Documents Department
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Automatic Stabilization

Description: This report lays more stress on the principles underlying automatic piloting than on the means of applications. Mechanical details of servomotors and the mechanical release device necessary to assure instantaneous return of the controls to the pilot in case of malfunction are not included. Descriptions are provided of various commercial systems.
Date: December 1936
Creator: Haus
Partner: UNT Libraries Government Documents Department
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Automatic Stabilization

Description: This report concerns the study of automatic stabilizers and extends it to include the control of the three-control system of the airplane instead of just altitude control. Some of the topics discussed include lateral disturbed motion, static stability, the mathematical theory of lateral motion, and large angles of incidence. Various mechanisms and stabilizers are also discussed.
Date: August 1936
Creator: Haus
Partner: UNT Libraries Government Documents Department
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Aviation and Insurance

Description: This article considers some of the causes which hinder the development of aircraft insurance. Different risks are discussed as well as the causes of aircraft accidents. Pilot error, poor airdromes, weather conditions, poorly adapted airplanes, and engine failures are all examined and some conclusions are made.
Date: May 1922
Creator: Mayo, R. H.
Partner: UNT Libraries Government Documents Department
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Aviation Engines in the Endurance Contest

Description: The contest for engines of great endurance had entries of 13 types by the following firms: Breguet, Farman, Fiat, Hispano-Suiza, Lorraine-Dietrich, Panhard-Levassor, Peugeot, Renault, and Salmson.
Date: December 1924
Creator: Lehr, G.
Partner: UNT Libraries Government Documents Department
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Aviation Fuels (With Especial Reference To "White Spirit")

Description: Gasoline, the fuel now used, is an extremely volatile and inflammable liquid capable of forming explosive mixtures, the cause of many catastrophes in aviation. It is therefore of special interest to investigate the possibility of using fuels which, while being less volatile than gasoline, would nevertheless enable this engine to function satisfactorily.
Date: February 1928
Creator: Dumanois, P.
Partner: UNT Libraries Government Documents Department
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Aviation in the Belgian Congo

Description: The establishment of air service in the Belgian Congo is detailed in this report. The airplanes, landing fields, and air routes are all discussed.
Date: July 1922
Creator: van Crombrugge, A.
Partner: UNT Libraries Government Documents Department
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Aviation Spirit - Past, Present, and Future

Description: The volatile fuel of the high-speed internal combustion engine has, in the past, consisted almost exclusively of the lighter distillates from crude petroleum. Alternative and supplementary fuels are discussed such as: tetraline, dekalin, alcohol, cyclo-hexenes.
Date: September 1923
Creator: Dunstan, A. E. & Thole, F. B.
Partner: UNT Libraries Government Documents Department
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Axial Superchargers

Description: Improvements, however, have been attained which permit a shortening of the structure without any impairment of the efficiency. The axial supercharger has a better efficiency and a simpler design than the radial supercharger. The relatively narrow range in which it operates satisfactorily should not be a very disturbing factor for practical flight problems. The length of this type of supercharger may be reduced considerably if some impairment in the efficiency is permitted.
Date: August 1944
Creator: Betz, A.
Partner: UNT Libraries Government Documents Department
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Bagnulo Heavy Fuel Internal Combustion Engine and Its Employment in Aviation

Description: We see with great satisfaction that Bagnulo's studies and experiments on his high-speed, heavy-fuel engines, promise to solve not only the general problem of economical power and hence of thermal efficiency, but also all other special problems, of weight and space, and, what is still more important, range of error.
Date: March 1922
Creator: Fiore, Amedeo
Partner: UNT Libraries Government Documents Department
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