Vibration and sound radiation of fluid-loaded stiffened plates with consideration of in-plane deformation

Abstract

A Ritz method is presented for computing the vibration and sound radiation of baffled rectangular plates reinforced by eccentric stiffeners. The model incorporates both bending, transverse shear and in-plane deformation of the plate, and bending, torsional, and extensional deformation of the stiffeners. The in-plane deformation of the plate, resulting from the eccentric stiffener deformations, has not been considered in previous studies. Relevant expressions of the kinetic and strain energies of the mechanical system are detailed. Numerical results of the in-vacuo natural frequencies for various configurations of plate thickness, stiffeners, and boundary conditions show the importance of in-plane displacements of the plate, especially when thick plates are involved. The comparisons in terms of in-vacuo natural frequencies between the present approach and available published results as well as FEM calculations show a good agreement. An example of structural response and sound radiation in water is also presented.