Abstract
This paper present a new approximate calculation method for three-dimensional nonlinear interactions between Stokes waves and submerged coastal structures. In the mathematical formulation, Green's Identity formula is used to express the distributions of the velocity potential on a horizontal plane, and a collocation method of matched eigenfunction expansions is also utilized to derive the linear relationships for the velocity potential and its normal derivative on the adjacent fluid region. The particular solution of the second-order boundary value problem, which satisfies the nonhomogeneous free surface boundary condition, is approximately expressed on the assumption that it has the same form of an eigenfunction in the vertical direction as that of the second-order Stokes solution.
