Flutter Control of a Lifting Surface via Visco-Hysteretic Vibration Absorbers

Abstract

In this paper, a visco-hysteretic vibration absorber (VA) is proposed to increase the flutter speed of an airfoil and enhance damping in the pre-and post-flutter regimes. The passive system consists of a parallel arrangement of a dashpot and a rateindependent hysteretic element, represented by the Bouc-Wen differential model. The equations of motion are obtained and various tools of linear and nonlinear dynamics are employed to study the effects of the visco-hysteretic VA in the pre-and postflutter ranges.

Numerical and experimental investigation of aeroviscoelastic systems

“…In this optimization, factors not considered in the present study, such as the thicknesses of the viscoelastic layers, arbitrary shapes of the viscoelastic elements, and the thermomechanical features of the viscoelastic materials could be used as design variables. Another aspect that deserves discussion is related to how the control strategy based on viscoelastic materials compares to other passive strategies suggested in literature, such as the one proposed by Lacarbonara and Cetraro [12], which consists of a parallel arrangement of a dashpot and a rate independent hysteretic element. In the authors' opinion, each strategy has its advantages and drawbacks.…”

“…A model for the dynamic behavior of viscoelastic materials in the frequency domain is obtained by performing the Fourier transformation of Eq. (12), and assuming null initial conditions. This leads to the following constitutive equation in the frequency domain:…”

Nonlinear dynamics enabled systems design and control

“…Practical implementations of HYS VAs deal with control of the base-excited primary resonance and random vibrations of beams and footbridges [15], flutter control of aircraft wings [16] and suspension bridges [18]. For suspension bridges, the indicial function approach and a linearized (condensed) model of suspension bridges were employed to study the onset of the flutter condition [17].…”

“…The rheological hysteretic component can be a device or an assembly of material components with nonlinear (memorydependent) constitutive behaviors [12] for which unloading occurs on distinct curves different from the so-called virgin loading curve (e.g., a series arrangement of a spring and a friction element, short steel wire ropes, shape memory wires [13,14]). These nonlinear VAs are proved to be effective for reducing by orders of magnitude the effects of sustained primary resonances in structures such as beams/bridges [15] or for control of self-excited mechanisms such as flutter in aircraft wings [16] and suspension bridges [17,18].…”

Passive Flutter Suppression Using a Nonlinear Tuned Vibration Absorber

“…In [22] , a nonlinear damping element was added in parallel with the LTVA to decrease the maximum LCO amplitude. Other nonlinear vibration absorbers, including the autoparametric vibration absorber [23,24] , the nonlinear energy sink [25−27] and the hysteretic tuned vibration absorber [28] , have also been considered to increase the effectiveness of vibration attenuation.…”