An inverse trigonometric shear deformation theory for supersonic flutter characteristics of multilayered composite plates

In this study, an inverse trigonometric shear deformation theory developed by the authors is extended to assess the flutter behavior of multilayered composite plates subjected to yawed supersonic flow. The shear deformation is considered in terms of an inverse cotangent function which yields non-linear distribution of shear stresses. A generalized finite element formulation is presented to consider the shear strain function based theories. The displacement field is modified by a precise involvement of additional field variables to ensure the implementation of C0 continuous finite element. First order piston theory is employed to consider the aerodynamic load. The applicability, validity and accuracy of the present mathematical treatment are ascertained by performing various numerical tests and comparing the present results with the existing results. The influences of various parameters such as lamination sequences, boundary conditions, material anisotropy, flow angles, etc. on the free vibration and flutter behavior are examined and significant conclusions are made. It is concluded that flow angles, lamination sequence and material anisotropy should be considered as essential design parameters for enhanced flutter boundary of supersonic vehicles.