Flutter analysis of delaminated composite box-beam using higher-order kinematics

The flutter analysis of delaminated box-beam has been performed using the Lagrange polynomial in Carrera Unified Formulation (CUF) framework. In this formulation, the cross-sectional displacement field of each layer can be defined by the arbitrary displacement variables using the Layerwise (LW) approach. The cross-section of the present structural model is discretized using the quadratic elements. The unsteady aerodynamic contribution has been obtained using Theodorsen's lift function. Subsequently, the structural and aeroelastic model has been defined using the Principle of Virtual Displacement (PVD) in the CUF framework. For verification of the present model, free variation analysis has been performed for delaminated and healthy composite structures. Furthermore, a composite box-beam model with single and multiple delaminations has been developed to perform free vibration and flutter analysis. This study supports the capability of the CUF model to perform flutter analysis of the complex model with multi-delaminated composite box-beam.