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Investigation of local heat-transfer and pressure drag characteristics of a yawed circular cylinder at supersonic speeds

Description: Local heat-transfer coefficients, temperature recovery factors, and pressure distributions were measured on the front side of a circular cylinder at a nominal Mach number of 3.9 over a range of free-stream Reynolds numbers from 2.1 x 10 to the 3rd power to 6.7 x 10 to the 3rd power and yaw angles from zero degrees to 44 degrees. Yawing the cylinder reduced the heat-transfer coefficients and the pressure drag coefficients. The amount of reduction may be predicted by a theory presented herein.
Date: January 24, 1956
Creator: Goodwin, Glen; Creager, Marcus O. & Winkler, Ernest L.
Partner: UNT Libraries Government Documents Department

Air flow around finned cylinders

Description: Report presents the results of a study made to determine the air-flow characteristics around finned cylinders. Air-flow distribution is given for a smooth cylinder, for a finned cylinder having several fin spacings and fin widths, and for a cylinder with several types of baffle with various entrance and exit shapes. The results of these tests show: that flow characteristics around a cylinder are not so critical to changes in fin width as they are to fin spacing; that the entrance of the baffle has a marked influence on its efficiency; that properly designed baffles increase the air flow over the rear of the cylinder; and that these tests check those of heat-transfer tests in the choice of the best baffle.
Date: November 7, 1935
Creator: Brevoort, M. J. & Rollin, Vern G.
Partner: UNT Libraries Government Documents Department

On Panel Flutter and Divergence of Infinitely Long Unstiffened and Ring-Stiffened Thin-Walled Circular Cylinders

Description: "A preliminary theoretical investigation of the panel flutter and divergence of infinitely long, unstiffened and ring-stiffened thin-walled circular cylinders is described. Linearized unsteady potential-flow theory is utilized in conjunction with Donnell's cylinder theory to obtain equilibrium equations for panel flutter. Where necessary, a simplified version of Flugge's cylinder theory is used to obtain greater accuracy. By applying Nyquist diagram techniques, analytical criteria for the location of stability boundaries are derived. A limited number of computed results are presented" (p. 475).
Date: January 11, 1956
Creator: Leonard, Robert W. & Hedgepeth, John M.
Partner: UNT Libraries Government Documents Department

On Panel Flutter and Divergence of Infinitely Long Unstiffened and Ring-Stiffened Thin-Walled Circular Cylinders

Description: Note presenting a theoretical investigation of the panel flutter and divergence of infinitely long, unstiffened and ring-stiffened thin-walled circular cylinders. Linearized unsteady potential-flow theory is utilized in conjunction with Donnell's cylinder theory to obtain equilibrium equations for panel flutter.
Date: April 1956
Creator: Leonard, Robert W. & Hedgepeth, John M.
Partner: UNT Libraries Government Documents Department

Principles involved in the cooling of a finned and baffled cylinder

Description: An analysis of the cooling problems for a finned cylinder is made on the basis of the known fundamental principles of heat transfer from pipes. Experimental results that support the analysis are presented. The results of previous investigations on the problem are evaluated on the basis of the analysis and the results. An illustration of the application of these principles to a specific problem is included.
Date: June 1938
Creator: Brevoort, M. J.
Partner: UNT Libraries Government Documents Department

Heat dissipation from a finned cylinder at different fin-plane/air-stream angles

Description: This report gives the results of an experimental determination of the temperature distribution in and the heat dissipation from a cylindrical finned surface for various fin-plane/air-stream angles. A steel cylinder 4.5 inches in diameter having slightly tapered fins of 0.30-inch pitch and 0.6 -inch width was equipped with an electrical heating unit furnishing 13 to 248 B.T.U. per hour per square inch of inside wall area. Air at speeds form 30 to 150 miles per hour was directed at seven different angles from 0 degrees to 90 degrees with respect to the fin planes. The tests show the best angle for cooling at all air speeds to be about 45 degrees. With the same temperature for the two conditions and with an air speed of 76 miles per hour, the heat input to the cylinder can be increased 50 percent at 45 degrees fin-plane/air-stream angle over that at 0 degrees.
Date: August 1932
Creator: Schey, Oscar W. & Biermann, Arnold E.
Partner: UNT Libraries Government Documents Department

Heat transfer from cylinders having closely spaced fins

Description: The heat-transfer coefficients have been determined for five steel cylinders having fins 1.22 inches wide and the spacing between the fins ranging from 0.022 to 0.131 inch. The cylinders were tested with and without baffles in a wind tunnel; they were also tested enclosed in jackets with the cooling air supplied by a blower. A maximum heat transfer was reached at a fin space of about 0.45 inch for the cylinders tested with each of the three methods of cooling investigated. The rise in temperature of the air passing between the fins and the change in flow pattern were found to be important factors limiting the heat transfer that may be obtained by decreasing the fin space. The use of baffles for directing the air around the cylinders with closely spaced fins proved very effective in increasing the over-all heat-transfer coefficient, provided that the spacing was not appreciably less than that for maximum heat transfer.
Date: May 1937
Creator: Biermann, Arnold E.
Partner: UNT Libraries Government Documents Department

The charging process in a high-speed, single-cylinder, four-stroke engine

Description: From Summary: "Experimental measurements and theoretical calculations were made on an aircraft-type, single cylinder engine, in order to determine the physical nature of the inlet process, especially at high piston speeds. The engine was run at speeds from 1,500 to 2,600 r.p.m. (mean piston speeds of 1,370 to 2,380 feet per minute). Measurements were made of the cylinder pressure during the inlet stroke and of the power output and volumetric efficiency. Measurements were also made, with the engine not running, to determine the resistance and mass of air in the inlet valve port at various crank angles. Results of analysis indicate that mass has an appreciable effect, but friction plays the major part in restricting flow. The observed fact that the volumetric efficiency is considerably less than 100 percent is attributed to thermal effects. An estimate was made of the magnitude of these effects in the present case, and their general nature is discussed."
Date: February 1939
Creator: Reynolds, Blake; Schecter, Harry & Taylor, E. S.
Partner: UNT Libraries Government Documents Department

Experimental investigation of the effect of yaw on rates of heat transfer to transverse circular cylinders in a 6500-foot-per-second hypersonic air stream

Description: Report describing equipment that can be used to shock-compress air by helium to 3660 degrees Rankine to generate a 6500-foot-per-second air stream with a flow duration of 40 milliseconds. The influence of yaw on rates of heat transfer to the same circular cylinders was investigated at angles of yaw up to 70 degrees.
Date: August 26, 1958
Creator: Cunningham, Bernard E. & Kraus, Samuel
Partner: UNT Libraries Government Documents Department

The inward bulge type buckling of monocoque cylinders 3: revised theory which considers the shear strain energy

Description: Report presenting the third part of an investigation dealing with the inward bulge type buckling of monocoque cylinders the theory of buckling in pure bending, which is refined through the consideration of the shear strain energy stored in the sheet covering, the assumption of a revised deflected shape of the rings, and the use of summations in place of some of the integrations of the preceding report.
Date: April 1945
Creator: Hoff, N. J. & Klein, Bertram
Partner: UNT Libraries Government Documents Department

The inward bulge type buckling of monocoque cylinders 2: experimental investigation of the buckling in combined bending and compression

Description: This paper is the second part of a series of reports on the inward bulge type buckling of monocoque cylinders. It presents the results of an experimental investigation of buckling in combined bending and compression. In the investigation it was found that the theory developed in part I of the present series predicts the buckling load in combined bending and compression with the same degree of accuracy as the older theory does in pure bending. In the realm covered by the experiments no systematic variation of the parameter N was observed. The analysis of the test results afforded a check on the theories of buckling of a curved panel. The agreement between experiment and theory was reasonably good. In addition, the effect of the end conditions upon the stress distribution under loads and upon initial stresses was investigated.
Date: October 1944
Creator: Hoff, N. J.; Fuchs, S. J. & Cirillo, Adam J.
Partner: UNT Libraries Government Documents Department

Stresses in and general instability of monocoque cylinders with cutouts 6: calculation of the buckling load of cylinders with side cutout subjected to pure bending

Description: Report presenting a strain-energy theory for the calculation of the buckling load in general instability of circular reinforced monocoque cylinders with a side cutout and subjected to pure bending.
Date: March 1948
Creator: Hoff, N. J.; Klein, Bertram & Boley, Bruno A.
Partner: UNT Libraries Government Documents Department

Stresses in and general instability of monocoque cylinders with cutouts 5: calculation of the stresses in cylinders with side cutout

Description: "Stresses were calculated by a numerical method in three reinforced monocoque cylinders subjected to pure bending. The cylinders were of circular cross section and were reinforced with 8 rings and either 8 or 16 stringers. There was a cutout on one side of each cylinder located symmetrically to the neutral plane and extending over 45, 90, or 135 degrees" (p. 1).
Date: January 1948
Creator: Hoff, N. J. & Klein, Bertram
Partner: UNT Libraries Government Documents Department

A preliminary investigation of exhaust-gas ejectors for ground cooling

Description: Report presenting a preliminary investigation to determine the suitability of ejectors actuated by the exhaust of a radial air-cooled aircraft engine for providing engine cooling air at the ground condition. Various length and diameter ejectors were tested for varying engine power for nine ejectors actuated by the exhaust of individual cylinders and three ejectors actuated by the exhaust of groups of three cylinders.
Date: July 1942
Creator: Manganiello, Eugene J.
Partner: UNT Libraries Government Documents Department

A numerical approach to the instability problem of monocoque cylinders

Description: Report presenting two closely related methods which employ operations tables that have been developed and used in the calculation of buckling load of a monocoque cylinder subjected to pure bending. The buckling loads of three cylinders with very different characteristics were calculated using the methods.
Date: April 1951
Creator: Boley, Bruno A.; Kempner, Joseph & Mayers, J.
Partner: UNT Libraries Government Documents Department

Strength tests of thin-walled elliptic duralumin cylinders in pure bending and in combined pure bending and torsion

Description: An analysis is presented of the results of tests made by the Massachusetts Institute of Technology and by the National Advisory Committee for Aeronautics on an investigation of the strength of thin-walled circular and elliptic cylinders in pure bending and in combined torsion and bending. In each of the loading conditions, the bending moments were applied in the plane of the major axis of the ellipse.
Date: June 1942
Creator: Lundquist, Eugene E. & Stowell, Elbridge Z.
Partner: UNT Libraries Government Documents Department

Stresses in and general instability of monocoque cylinders with cutouts 3: calculation of the buckling load of cylinders with symmetric cutout subjected to pure bending

Description: Report presenting a strain-energy theory for the calculation of the buckling load in pure bending of reinforced monocoque cylinders with a symmetric cutout on the compression side and buckle according to the general instability pattern.
Date: May 1947
Creator: Hoff, N. J.; Boley, Bruno A. & Klein, Bertram
Partner: UNT Libraries Government Documents Department

Stresses in and general instability of monocoque cylinders with cutouts 2: calculation of the stresses in a cylinder with a symmetric cutout

Description: A numerical procedure is presented for the calculation of the stresses in a monocoque cylinder with a cutout. In the procedure the structure is broken up into a great many units; the forces in these units corresponding to specified distortions of the units are calculated; a set of linear equations is established expressing the equilibrium conditions of the units in the distorted state; and the simultaneous linear equations are solved. A fully worked out numerical example, corresponding to the application of a pure bending moment, gave results in good agreement with experiments carried out earlier at the Polytechnic Institute of Brooklyn.
Date: June 1946
Creator: Hoff, N. J.; Boley, Bruno A. & Klein, Bertram
Partner: UNT Libraries Government Documents Department

Preliminary investigation of the effect of a rotating cylinder in a wing

Description: Into the leading edge of a wing with arbitrary cross-section, there is introduced a cylinder, which can be rotated by an electric motor by means of a cord. Observations were made in the wind tunnel on how the lift at different wind velocities was affected by rotating this cylinder.
Date: March 1925
Creator: Wolff, E. B.
Partner: UNT Libraries Government Documents Department

Comparison of several methods of predicting the pressure loss at altitude across a baffled aircraft-engine cylinder

Description: Several methods of predicting the compressible-flow pressure loss across a baffled aircraft-engine cylinder were analytically related and were experimentally investigated on a typical air-cooled aircraft-engine cylinder. Tests with and without heat transfer covered a wide range of cooling-air flows and simulated altitudes from sea level to 40,000 feet. Both the analysis and the test results showed that the method based on the density determined by the static pressure and the stagnation temperature at the baffle exit gave results comparable with those obtained from methods derived by one-dimensional-flow theory. The method based on a characteristic Mach number, although related analytically to one-dimensional-flow theory, was found impractical in the present tests because of the difficulty encountered in defining the proper characteristic state of the cooling air. Accurate predictions of altitude pressure loss can apparently be made by these methods, provided that they are based on the results of sea-level tests with heat transfer.
Date: October 9, 1945
Creator: Neustein, Joseph & Schafer, Louis J., Jr.
Partner: UNT Libraries Government Documents Department

Experimental stress analysis of stiffened cylinders with cutouts: Pure bending

Description: Bending tests were made on a cylindrical semimonocoque shell of circular cross section. The cylinder was tested without a cutout and then with a rectangular cutout which was successively enlarged through six sizes varying from 30 degrees to 130 degrees in circumference and from 1 to 2 bays in length. Strain measurements were made with resistance-type wire strain gages near the cutout on the stringers, the skin, and the rings for each size of cutout, and the stresses obtained are presented in tables. (author).
Date: March 1954
Creator: Schlechte, Floyd R. & Rosecrans, Richard
Partner: UNT Libraries Government Documents Department

Experimental stress analysis of stiffened cylinders with cutouts: Shear load

Description: A cylindrical semimonocoque shell of circular cross section was mounted as a cantilever and loaded by a direct shear at the tip. The cylinder was tested with no cutout, with a rectangular cutout on the tension side, and with the cutout centered on the neutral axis on one side of the cylinder. The cutout was successively enlarged through six sizes varying from 30 degrees to 130 degrees in circumference and from 1 and 2 bays in length. Strain measurements were made with resistance-type wire strain gages near the cutout on the stringers, the skin, and the rings for each case, and the stresses obtained are presented in tables. (author).
Date: July 1954
Creator: Schlechte, Floyd R. & Rosecrans, Richard
Partner: UNT Libraries Government Documents Department