Passive control of wing/store flutter [PDF]
Results are presented for a passive flutter suppression approach known as the decoupler pylon. The decoupler pylon dynamically isolates the wing from store pitch inertia effects by means of soft spring/damper elements assisted by a low frequency feedback
Cazier, F. W., Jr. +2 more
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Multifunction tests of a frequency domain based flutter suppression system [PDF]
The process is described of analysis, design, digital implementation, and subsonic testing of an active control flutter suppression system for a full span, free-to-roll wind tunnel model of an advanced fighter concept.
Adams, William M., Jr. +1 more
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Final design and fabrication of an active control system for flutter suppression on a supercritical aeroelastic research wing [PDF]
The final design and hardware fabrication was completed for an active control system capable of the required flutter suppression, compatible with and ready for installation in the NASA aeroelastic research wing number 1 (ARW-1) on Firebee II drone flight
Hodges, G. E., Mcgehee, C. R.
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Development of aeroelastic analysis methods for turborotors and propfans, including mistuning [PDF]
The NASA Lewis aeroelastic research program is focused on unstalled and stalled flutter, forced response, and whirl flutter of turborotors and propfans.
Kaza, Krishna Rao V.
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Flutter suppression digital control law design and testing for the AFW wind-tunnel model [PDF]
Design of a control law for simultaneously suppressing the symmetric and antisymmetric flutter modes of a string mounted fixed-in-roll aeroelastic wind tunnel model is described.
Mukhopadhyay, Vivek
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Improvements of Zeyded method for calculating flutter of flat panels [PDF]
, 1972 Method for calculating flutter boundaries and estimating stresses in infinite spanwise array of panels is presented. Numerical analyses are included for pinned edge panels, isotropic panel material, zero viscous damping, and no elastic foundation. Design
Yates, J. E.
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Optical measurement of unducted fan flutter [PDF]
A nonintrusive optical method is described for flutter vibrations in unducted fan or propeller rotors and provides detailed spectral results for two flutter modes of a scaled unducted fan. The measurements were obtained in a high-speed wind tunnel.
Kurkov, Anatole P., Mehmed, Oral
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Status and future plans of the Drones for Aerodynamic and Structural Testing (DAST) program [PDF]
Results from flight tests of the ARW-1 research wing are presented. Preliminary loads data and experiences with the active control system for flutter suppression are included along with comparative results of test and prediction for the flutter boundary ...
Murrow, H. N.
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Evaluation of four subcritical response methods for on-line prediction flutter onset in wind-tunnel tests [PDF]
The methods were evaluated for use in tests where the flutter model is excited solely by airstream turbulence. The methods were: randomdec, power-spectral-density, peak-hold, and cross-spectrum.
Doggett, R. V., Jr. +3 more
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A preliminary study of the effects of vortex diffusers (winglets) on wing flutter [PDF]
Some experimental flutter results are presented for a simple, flat-plate wing model and for the same wing model equipped with two different upper surface vortex diffusers over the Mach number range from about 0.70 to 0.95.
Doggett, R. V., Jr., Farmer, M. G.
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