Nonlinear flutter of aerothermally buckled composite shells with damping treatments

Finite element analyses of the aerothermoelastic behavior of aerothermally buckled cylindrical composite shells with various damping treatments were implemented using the theory of layerwise displacement field. The arc-length method and iterative nonlinear scheme were taken up to estimate the post-buckling deformation of composite shells due to aerothermal loads. The complex modulus was adopted to take into account the effects of viscoelastic damping. The post-buckling behaviors and aeroelastic characteristics, under thermal loads, of several damped composite shells were investigated with various damping treatments including free layer and constrained layer and sandwiched damping layers. The results show that the flutter boundary of the cylindrical composite panels with viscoelastic layers can be remarkably affected by the aerothermally buckled shapes and damping treatments. Further, the proper damping treatments, coupled with thermal loads, can improve aerothermoelastic characteristics, resulting in the increase of the flutter boundary.