Supersonic panel flutter analysis of viscoelastic sandwich plates accounting for thickness deformation

The supersonic panel flutter of sandwich plates with thick viscoelastic cores is investigated. The displacement component are assumed to vary quadratically through the thickness, allowing for inclusion of the thickness deformation effects in theanalysis. The viscoelastic material is modeled by the frequency and temperature dependent complex modulus. The Piston theory is also used for describing the supersonic aerodynamic pressure. The equations ofmotion are derived by the Hamilton’s principle and discretized using the Galerkin method. Considering that the viscoelastic material is described in the frequencydomain, an iterative procedure similar to the conventional p-k method is adopted to determine flutter boundaries. It is found that the thickness deformation may give higher estimation of the flutter speed,especially for cases with thinner top layers and thicker cores.