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Aerodynamic Characteristics of Airfoils 4: Continuation of Reports Nos. 93, 124, and 182

Description: This collection of data on airfoils has been made from the published reports of a number of the leading Aerodynamic Laboratories of this country and Europe. The information which was originally expressed according to the different customs of the several laboratories is here presented in a uniform series of charts and tables suitable for the use of designing engineers and for purposes of general reference. The authority for the results here presented is given as the name of the laboratory at whi… more
Date: September 1926
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Air Flow in Open-Throat Wind Tunnels

Description: "Tests were conducted on the 6-inch wind tunnel of the National Advisory Committee for Aeronautics to form a part of a research on open-throat wind tunnels. The primary object of this part of the research was to study a type of air pulsation which has been encountered in open-throat tunnels, and to find the most satisfactory means of eliminating such pulsations. In order to do this it was necessary to study the effects of different variable on all of the important characteristics of the tunnel"… more
Date: September 26, 1928
Creator: Jacobs, Eastman N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coefficients of discharge of fuel-injection nozzles for compression-ignition engines

Description: "This report presents the results of an investigation to determine the coefficients of discharge of nozzles with small, round orifices of the size used with high-speed compression-ignition engines. The injection pressures and chamber back pressures employed were comparable to those existing in compression-ignition engines during injection. The construction of the nozzles was varied to determine the effect of the nozzle design on the coefficient. Tests were also made with nozzles assembled in an… more
Date: September 11, 1930
Creator: Gelalles, A. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some approximate equations for the standard atmosphere

Description: This report contains the derivation of a series of simple approximate equations for density ratios and for the pressure ratio in the standard atmosphere. The accuracy of the various equations is discussed and the limits of applications are given. Several of these equations are in excellent agreement with the standard values.
Date: September 19, 1930
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Static thrust of airplane propellers

Description: Static thrust data from more than 100 airplane propeller tests are collected from various sources and combined in working charts, from which the static thrust coefficient may be readily determined. The available data cover practically all types of propellers and are in good agreement.
Date: September 1932
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The drag of two streamline bodies as affected by protuberances and appendages

Description: This report presents the results of wind tunnel tests of two airship models conducted to determine the drag coefficients at zero pitch, and the effect of fins and cars and of flat and streamlined protuberances located at various positions along the hull. During the investigation the stern of one model was rounded off to produce a blunter shape. The extreme range of the Reynolds number based on the over-all length of the models was from 1,300,000 to 33,000,000. At large values of the Reynolds nu… more
Date: September 26, 1932
Creator: Abbott, Ira H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some Factors Affecting Combustion in an Internal-Combustion Engine

Description: "An investigation of the combustion of gasoline, safety, and diesel fuels was made in the NACA combustion apparatus under conditions of temperature that permitted ignition by spark with direct fuel injection, in spite of the compression ratio of 12.7 employed. The influence of such variables as injection advance angle, jacket temperature, engine speed, and spark position was studied. The most pronounced effect was that an increase in the injection advance angle (beyond a certain minimum value) … more
Date: September 11, 1934
Creator: Rothrock, A. M. & Cohn, Mildred
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The effect of baffles on the temperature distribution and heat-transfer coefficients of finned cylinders

Description: This report presents the results of an investigation to determine the effect of baffles on the temperature distribution and the heat-transfer coefficient of finned cylinders. The tests were conducted in a 30-inch wind tunnel on electrically heated cylinders with fins of 0.25 and 0.31 inch pitch. The results of these tests showed that the use of integral baffles gave a reduction of 31.9 percent in the rear wall temperatures and an increase of 54.2 percent in the heat transfer coefficient as comp… more
Date: September 26, 1934
Creator: Schey, Oscar W. & Rollin, Vern G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Further Studies of Flame Movement and Pressure Development in an Engine Cylinder

Description: This report describes an investigation using a stroboscopic apparatus for observing flame movement through a large number of small windows distributed over the head of a spark-ignition engine in following flame spread with combustion chambers of different shapes at two engine speed and for a variety of spark-plug locations including single and twin ignition. The principal factors influencing flame movement in the engine are discussed, and the lack of reliable information regarding their separat… more
Date: September 1935
Creator: Marvin, Charles F., Jr.; Wharton, Armistead & Roeder, Carl H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some Effects of Argon and Helium Upon Explosions of Carbon Monoxide and Oxygen

Description: Report presents the results of an investigation conducted to study the effects of the inert gases, argon and helium, upon flame speed and expansion ratio in exploding mixtures of carbon monoxide, oxygen and water. For the particular gas mixtures investigated the results show that: (1) With the possible exception of helium in small amounts the addition of inert gas always produces decreased flame speed and expansion ratio; (2) like volumes of argon and helium have very different effects upon fla… more
Date: September 25, 1935
Creator: Fiock, Ernst F. & Roeder, Carl H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Rolling Friction of Several Airplane Wheels and Tires and the Effect of Rolling Friction on Take-Off

Description: This report presents the results of tests made to determine the rolling friction of airplane wheels and tires under various conditions of wheel loading, tire inflation pressure, and ground surface. The effect of wheel-bearing type was also investigated. Six pairs of wheels and tires were tested including two sizes of each of the types designated as standard (high pressure), low pressure, and extra low pressure. The results of calculations intended to show the effect of variations in rolling fri… more
Date: September 19, 1936
Creator: Wetmore, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Interrelation of Exhaust-Gas Constituents

Description: This report presents the results of an investigation conducted to determine the interrelation of the constituents of the exhaust gases of internal-combustion engines and the effect of engine performance on these relations. Six single-cylinder, liquid-cooled tests engines and one 9-cylinder radial air-cooled engine were tested. Various types of combustion chambers were used and the engines were operated at compression ratios from 5.1 to 7.0 using spark ignition and from 13.5 to 15.6 using compre… more
Date: September 7, 1937
Creator: Gerrish, Harold C. & Voss, Fred
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Column Strength of Tubes Elastically Restrained Against Rotation at the Ends

Description: Report presents the results of a study made of the effects of known end restraint on commercially available round and streamline tubing of chromium-molybdenum steel, duralumin, stainless steel, and heat-treated chromium-molybdenum steel; and a more accurate method than any previously available, but still a practical method, was developed for designing compression members in riveted or welded structures, particularly aircraft. Two hundred specimens were tested as short, medium-length, and long c… more
Date: September 9, 1937
Creator: Osgood, William R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The knocking characteristics of fuels in relation to maximum permissible performance of aircraft engines

Description: An analysis is presented of the relationship of various engine factors to knock in preignition in an aircraft engine. From this analysis and from the available experimental data, a method of evaluating the knocking characteristics of the fuel in an aircraft-engine cylinder is suggested.
Date: September 14, 1938
Creator: Rothrock, A. M. & Biermann, Arnold E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A study of air flow in an engine cylinder

Description: A 4-stroke-cycle test engine was equipped with a glass cylinder and the air movements within it were studied while the engine was being motored. Different types of air flow were produced by using shrouded intake valves in various arrangements and by altering the shape of the intake-air passage in the cylinder head. The air movements were made visible by mixing feathers with the entering air, and high-speed motion pictures were taken of them so that the air currents might be studied in detail an… more
Date: September 15, 1938
Creator: Lee, Dana W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanism of flutter: A theoretical and experimental investigation of the flutter problem

Description: 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 … more
Date: September 22, 1938
Creator: Theodorsen, Theodore & Garrick, I. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Column Strength of Two Extruded Aluminum-Alloy H-Sections

Description: "Extruded aluminum-alloy members of various cross sections are used in aircraft as compression members either singly or as stiffeners for aluminum-alloy sheet. In order to design such members, it is necessary to know their column strength or, in the case of stiffeners, the value of the double modulus, which is best obtained for practical purposes from column tests. Column tests made on two extruded h-sections are described, and column formulas and formulas for the ratio of the double modulus to… more
Date: September 30, 1938
Creator: Osgood, William R. & Holt, Marshall
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flame Speeds and Energy Considerations for Explosions in a Spherical Bomb

Description: "Simultaneous measurements were made of the speed of flame and the rise in pressure during explosions of mixtures of carbon monoxide, normal heptane, iso-octane, and benzene in a 10-inch spherical bomb with central ignition. From these records, fundamental properties of the explosive mixtures, which are independent of the apparatus, were computed. The transformation velocity, or speed at which flame advances into and transforms the explosive mixture, increases with both the temperature and the … more
Date: September 28, 1939
Creator: Fiock, Ernest F.; Marvin, Charles F., Jr.; Caldwell, Frank R. & Roeder, Carl H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation of air inlet and outlet openings on a streamline body

Description: In connection with the general problem of providing air flow to an aircraft power plant located within a fuselage, an investigation was conducted in the Langley 8-foot high-speed tunnel to determine the effect on external drag and pressure distribution of air inlet openings located at the nose of a streamline body. Air outlet openings located at the tail and at the 21-percent and 63-percent stations of the body were also investigated. Boundary layer transition measurements were made and correla… more
Date: September 11, 1940
Creator: Becker, John V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preignition characteristics of several fuels under simulated engine conditions

Description: "The preignition characteristics of a number of fuels have been studied under conditions similar to those encountered in an engine. These conditions were simulated by suddenly compressing a fuel-air mixture in contact with an electrically heated hot spot in the cylinder head of the NACA combustion apparatus. Schlieren photographs and indicator cards were taken of the burning, and the hot-spot temperatures necessary to cause ignition under various conditions were determined" (p. 121).
Date: September 16, 1940
Creator: Spencer, R. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Use of Residue Theory for Treating the Subsonic Flow of a Compressible Fluid

Description: "A new mathematical technique, due to Milne-Thomson, is used to obtain an improved form of the method of Poggi for calculating the effect of compressibility on the subsonic flow past an obstacle. By means of this new method, the difficult surface integrals of the original Poggi method can be replaced by line integrals. These line integrals are then solved by the use of residue theory. In this way an equation is obtained giving the second-order effect of compressibility on the velocity of the fl… more
Date: September 8, 1941
Creator: Kaplan, Carl
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of an NACA 23012 Airfoil With 30 Percent-Chord Venetian-Blind Flaps

Description: Report presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of a NACA 23012 airfoil with 30-percent-chord venetian-blind flaps having one, two, three, and four slats of Clark y section. The three-slat arrangements was aerodynamically the best of those tested but showed practically no improvement over the comparable arrangement used in the preliminary tests published in NACA Technical Report No. 689. The multiple-slat flaps gave slightly higher lift coefficients tha… more
Date: September 17, 1941
Creator: Rogallo, F. M. & Spano, Bartholomew S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Test of single-stage axial-flow fan

Description: "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 s… more
Date: September 22, 1941
Creator: Bell, E. Barton
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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