Prediction of Eigen-frequency of Stiffened Sandwich Composite Plates Using Finite Elements

This paper presents the natural vibration analysis of stiffened sandwich composite plates (SSCP) using finite elements. The geometry of SSCP mid-plane kinematics has been modelled by using ANSYS parametric design language (APDL) code, which is based on first order shear deformation theory (FSDT). The whole SSCP has been formulated using an eight node serendipity shell 281 element. Firstly, the eigen-frequency values of unstiffened sandwich plate and stiffened composite plates are validated with available benchmark results. Then, the natural frequencies of SSCP by using different combination of lamina orientation as well as no of stiffeners are examined by solving suitable numerical examples and findings are debated in detail.