Numerical and experimental investigation of aeroviscoelastic systems

Abstract Viscoelastic materials have been widely used for the purpose of passive vibration mitigation in various types of mechanical systems, including, industrial machinery, civil structures and vehicles. In this paper, the use of those materials in aeroelastic systems is investigated, with emphasis placed on the influence of the viscoelastic behavior on the flutter speeds of two-degree-of-freedom typical section models, in which viscoelastic elements are introduced in addition to elastic elements associated to heave and pitch motions. The equations of motion of the aeroelastic system are modified to account for the dependence of the viscoelastic behavior on frequency and temperature, by using the concepts of complex modulus and shift factor. The aerodynamic forces and moments in subsonic regime are modeled according to Theodorsen's method. Numerical simulations are conducted to evaluate the influence of the addition of viscoelastic elements on the flutter speed and elucidate the separated influences of stiffness and damping additions. An experimental wind tunnel setup consisting of a rigid wing supported by flexible elements in pitch and plunge motions has been modified to enable the introduction of viscoelastic elements in parallel to those flexible elements. For various configurations of viscoelastic additions, the flutter instability is characterized from vibration measurements performed for increasing flow speeds in the vicinity of the stability boundary. The experimental results are used to validate the numerical model derived for the aeroviscoelastic system and confirm both qualitatively and quantitatively the predictions of the simulations, especially the possibility of increasing the flutter speed by the inclusion of viscoelastic materials.

[1]  Sondipon Adhikari,et al.  Iterative Methods for Eigenvalues of Viscoelastic Systems , 2011 .

[2]  L. S. Leão,et al.  Flutter suppression of plates subjected to supersonic flow using passive constrained viscoelastic layers and Golla–Hughes–McTavish method , 2016 .

[3]  Muhammad R. Hajj,et al.  Airfoil control surface discontinuous nonlinearity experimental assessment and numerical model validation , 2016 .

[4]  J. T. Foughner,et al.  Passive control of wing/store flutter , 1980 .

[5]  Victor Giurgiutiu,et al.  Review of Smart-Materials Actuation Solutions for Aeroelastic and Vibration Control , 2000 .

[6]  E. Nissim,et al.  Flutter suppression using active controls based on the concept of aerodynamic energy , 1971 .

[7]  Bijan Samali,et al.  Use of viscoelastic dampers in reducing wind- and earthquake-induced motion of building structures , 1995 .

[8]  Liviu Librescu,et al.  Advances in the linear/nonlinear control of aeroelastic structural systems , 2005 .

[9]  M. L. Drake,et al.  Aerospace Structures Technology Damping Design Guide. Volume 2. Design Guide , 1985 .

[10]  P. Chen.  Damping Perturbation Method for Flutter Solution: The g-Method , 2000 .

[11]  Maurício Vicente Donadon,et al.  Flutter suppression of plates using passive constrained viscoelastic layers , 2016 .

[12]  Mario Lázaro,et al.  Dynamic analysis of frame structures with free viscoelastic layers: New closed-form solutions of eigenvalues and a viscous approach , 2013 .

[13]  R. Christensen.  Theory of viscoelasticity : an introduction , 1971 .

[14]  T. A. Weisshaar,et al.  Panel flutter suppression using adaptive material actuators , 1994 .

[15]  David I. G. Jones.  Handbook of Viscoelastic Vibration Damping , 2001 .

[16]  David L. Gray,et al.  Development and demonstration of a flutter-suppression system using active controls. [wind tunnel tests] , 1975 .

[17]  Noureddine Bouhaddi,et al.  Component mode synthesis combining robust enriched Ritz approach for viscoelastically damped structures , 2010 .

[18]  Mohan D. Rao,et al.  Recent applications of viscoelastic damping for noise control in automobiles and commercial airplanes , 2003 .

[19]  Dewey H. Hodges,et al.  Introduction to Structural Dynamics and Aeroelasticity , 2002 .

[20]  Mario A. Rotea,et al.  Aeroservoelastic Tailoring with Piezoelectric Materials: Actuator Optimization Studies , 1994 .

[21]  T. Theodorsen.  General Theory of Aerodynamic Instability and the Mechanism of Flutter , 1934 .

[22]  Craig G. Merrett,et al.  Elastic and viscoelastic panel utter in incompressible, subsonic and supersonic ows , 2010 .

[23]  Walter Lacarbonara,et al.  Flutter Control of a Lifting Surface via Visco-Hysteretic Vibration Absorbers , 2011 .

[24]  Muhammad R. Hajj,et al.  Effects of combined hardening and free-play nonlinearities on the response of a typical aeroelastic section , 2016 .