Scaled boundary FEM solution of short-crested wave diffraction by a vertical cylinder

Abstract

The scaled boundary finite-element method (SBFEM) is a novel semi-analytical method developed in the elasto-statics and elasto-dynamics areas that has the advantages of combining the finite-element method with the boundary-element method. The SBFEM method weakens the governing differential equation in the circumferential direction and solves the weakened equation analytically in the radial direction. It has the inherent advantage of solving the unbounded fluid dynamic problem. In this paper, the boundary-value problem composed of short-crested waves diffracted by a vertical circular cylinder is solved by SBFEM. Only the cylinder boundary is discretized with curved surface finite-elements on the circumference of the cylinder, while the radial differential equation is solved completely analytically. The computation of the diffraction force based on the present SBFEM solution demonstrates a high accuracy achieved with a small number of surface finite-elements. The method can be extended to solve more complex wave-structure interaction problems resulting in direct engineering applications.