Time-domain structural-acoustic analysis of composite plates subjected to moving dynamic loads

Abstract This paper is concerned with the numerical analysis of structural and acoustic behaviors of composite laminated plates under the action of moving loads. The plate is assumed to be immersed in a compressible inviscid fluid. The moving loads may traverse on the surface of the plate along arbitrarily-shaped curved trajectories. The structural model of the plate is formulated using a modified variational principle combined with a multilevel partitioning procedure (i.e., individual layer and layer segment). The exact 3-D theory of elasticity is employed for the structural modeling in order to accommodate the analysis of arbitrarily thick composite plates, and the displacement field of each layer segment is approximated by Chebyshev orthogonal polynomials. A time-domain boundary element method based on Kirchhoff integral formulation is adopted to couple with the structural model of the plate to evaluate the radiated sound pressure of the fluid. Assessment of the accuracy of the present method is made by comparing the solutions attained from the coupled finite element/boundary element method. The effects of the velocities and trajectories of the moving loads on the dynamic responses of composite sandwich plates as well as the far-field radiated sound are investigated. The modal contributions to the vibro-acoustic responses of the plates are also discussed.