Free vibration of composite spherical shell cap with and without a cutout

The free vibration of composite spherical shell cap with and without a cutout is investigated. The analysis is carried out using the finite element method based on a higher-order shear deformation theory. An eight noded degenerated isoparametric shell element with nine degrees of freedom at each node is considered. Results are presented for axisymmetric free vibration of composite spherical shell cap with and without a cutout. The effects of number of plies, radius to thickness ratio, boundary conditions and cutout size on the fundamental frequency of orthotropic and laminated composite spherical shell cap are studied.