Free Vibration Analysis of Variable Stiffness Laminate Composite Shell Panel Using HSDT and FE Approach

In this current research work, the modal analysis of variable stiffness composite laminate (VSCL) shell panels is analyzed. This analysis is facilitated by a numerical model based on higher-order shear deformation theory (HSDT) and finite element (FE) approaches. The VSCL configuration is achieved by incorporating curved fibers as reinforcement. The displacement kinematics of the shell are modelled up to the third order of thickness coordinates, ensuring an accurate representation of the shell's behavior. The physical model of the shell panel is discretized using nine-noded isoperimetric elements, each offering a comprehensive depiction of the panel's geometry and behavior with 81 degrees of freedom per element. The governing differential equation is derived using the energy method, providing a robust foundation for the numerical model. To verify the model's utilization characteristics, element convergence and accuracy tests are conducted initially. Further, the capability of the developed kinematic model is expanded by exploring various parametric examples. These examples include investigating the influences of curvature ratio, shell thickness ratio, orthotropic ratio, and boundary conditions on the modal analysis of laminated composite cylindrical structures. Each parametric study is discussed in detail to provide comprehensive insights into the influence of the VSCL panels under different conditions.