A semi-analytical method to simulate hydroelastic slamming of 2D structural sections by coupling Wagner theory with the finite element method

Abstract

A semi-analytical method based on coupling Wagner theory with the finite element method is applied to numerically simulate hydroelastic slamming of arbitrary symmetric 2D structural sections subject to a constant impact velocity or to free fall motion. The averaged elastic velocity method is adopted to consider the influence of the elastic response on the distribution of the slamming load. A coupled dynamic equation is established to govern the fluid-structural interaction. The nonlinear pressure term improves accuracy. To validate the method, numerically predicted structural deformations and the associated strains during impact for several wedge-shaped sections and a cylindrical shell are compared with published results. The results show that the averaged elastic velocity method is efficient in estimating the structure dynamics. The effect of the nonlinear pressure term on hydroelastic structural dynamics is parametrically studied by considering wedge sections with different deadrise angles and with the elastic bottom plating under different end constraints. This nonlinear pressure term ensures reliably predicted hydroelastic structural responses, especially for wedges of larger deadrise angles and smaller hydroelastic properties. The proposed method provides an efficient tool to estimate structural strength under slamming during the initial design stage of the marine or aerospace structure.