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Wind-tunnel investigation of transonic aileron flutter

Description: Report presenting a partial-span wing tested to determine the cause of a flutter which had occurred in high-speed flight. Changes were made to the wing stiffness, location of the center of gravity of the wing, and the mass balance of the aileron. Results regarding the effect of wing changes on flutter, effect of aileron changes on flutter, shock-wave study, and static aerodynamic coefficients are provided.
Date: June 9, 1949
Creator: Erickson, Albert L. & Mannes, Robert L.
Partner: UNT Libraries Government Documents Department

The effects of various parameters, including Mach number, on propeller-blade flutter with emphasis on stall flutter

Description: Report presenting an investigation of the effects of many of the parameters significant to wing flutter on several untwisted rotating models to determine their significance with respect to stall flutter of propeller blades. The parameters included torsional stiffness, section thickness ratio, sweepback, length-chord ratio, section center-of-gravity location, blade taper, Mach number, and fluid density. Results regarding the considerations on method of presentation, experimental data and discussion, some possible applications, and a comparison of experiment with classical-flutter theory are provided.
Date: January 1955
Creator: Baker, John E.
Partner: UNT Libraries Government Documents Department

Recent experimental flutter studies

Description: Report presenting some highlights of recent experimental studies of flutter at high speeds. Flutter problems have become more varied with the advent of transonic flight and importance of aeroelasticity, and the flutter field has merged with other aspect of aeroelasticity such as divergence and buffeting. The two main subjects of flutter, classical flutter and stall flutter, are explored in these studies.
Date: June 12, 1951
Creator: Regier, Arthur A. & Martin, Dennis J.
Partner: UNT Libraries Government Documents Department

Initial experiments on flutter of unswept cantilever wings at Mach number 1.3

Description: Report presenting tunnel testing of the flutter of 12 widely different unswept cantilever wings with a variety of mass-density parameters, center-of-gravity positions, and elastic-axis positions. Results regarding the flutter parameters, flutter-speed coefficients, effect of airfoil-section shape on flutter, and aspect-ratio effects are provided.
Date: November 1954
Creator: Tuovila, W. J.; Baker, John E. & Regier, Arthur A.
Partner: UNT Libraries Government Documents Department

Experimental investigation of the oscillating forces and moments on a two-dimensional wing equipped with an oscillating circular-arc spoiler

Description: Report presenting an investigation in the flutter research tunnel to determine the oscillating forces and moments on a two-dimensional wing equipped with an oscillating circular-arc spoiler. The study indicated that force and moment coefficients and their phase angles are affected by Reynolds number, Mach number, and reduced frequency.
Date: January 12, 1954
Creator: Clevenson, Sherman A. & Tomassoni, John E.
Partner: UNT Libraries Government Documents Department

Experimental investigation of the effects of sweepback on the flutter of a uniform cantilever wing with a variably located concentrated mass

Description: Report presenting data from 95 subsonic flutter tests conducted in the flutter research tunnel on untapered cantilever wings with sweepback angles of 0, 45, and 60 degrees and carrying a single concentrated weight. The primary purpose of the investigation was to present experimental information to be used to evaluate analytical procedures for determining the flutter speed of weighted sweptback wings. The dynamic pressure, flutter velocity, Mach number, natural and flutter frequencies, and phase-angle relationships of the stresses for the natural and flutter frequencies are presented.
Date: August 31, 1949
Creator: Nelson, Herbert C. & Tomassoni, John E.
Partner: UNT Libraries Government Documents Department

Investigation of flutter characteristics of three low-aspect-ratio all-movable half-span control surfaces at Mach numbers from 1.49 to 2.87

Description: Report presenting the results of a supersonic flutter investigation of three low-aspect-ratio control surfaces, two which had all-movable controls and one with a fixed cutout. Experimental results are provided and compared to calculations using the piston theory for plan form 2. Modifications for improving the flutter of the various control surfaces are also described.
Date: May 2, 1958
Creator: Morgan, Homer G.; Figge, Irving E. & Presnell, John G., Jr.
Partner: UNT Libraries Government Documents Department

Free-flight flutter tests in the transonic and low supersonic speed range of three low-aspect-ratio swept, tapered wings on rocket-propelled vehicles

Description: Report presenting flutter data obtained with the use of rocket-propelled vehicles in the transonic and low supersonic speed ranges for three low-aspect-ratio, highly tapered, swept wings. Structural influence coefficients were obtained for each of the three plan forms and calculated mode shapes and frequencies are provided. Time histories for each of the configurations also demonstrate the flutter pattern of each wing.
Date: March 19, 1956
Creator: Lauten, William T., Jr. & O'Kelly, Burke R.
Partner: UNT Libraries Government Documents Department

Vibration surveys of the P-47-B rudder and fin-rudder assembly

Description: Report presenting a study of the flutter characteristics of the P-47 tail assembly, which included replacing the original fabric-covered rudder with a metal-covered rudder and reinforcing the fin. Figures are provided for different configurations and the cycles per second under the same conditions are provided.
Date: April 1943
Creator: Theodorsen, Theodore & Regier, Arthur A.
Partner: UNT Libraries Government Documents Department

Effect of the lift coefficient on propeller flutter

Description: Report presenting flutter of propellers at high angles of attack and flutter data obtained in connection with tests of models of large wind-tunnel propellers. The stall flutter speed was found to be much lower than the calculated classical flutter speed. That flutter speed is only obtainable if the propeller operates at the ideal angle of zero twist.
Date: July 1945
Creator: Theodorsen, Theodore & Regier, Arthur A.
Partner: UNT Libraries Government Documents Department