Second Order Diffraction and Radiation of a Floating Body With Small Forward Speed

Abstract

The formulation of the secondorder wavecurrentbody problem in the inertial coordinate system involves higherorder derivatives in the body boundary condition. A new method taking advantage of the bodyfixed coordinate system in the near field is presented to avoid the calculation of higherorder derivatives in the body boundary condition. The new method has an advantage over the traditional method when the body surface has a sharp corner or high curvature. The nonlinear wave diffraction and forced oscillation of floating bodies are studied up to second order in wave slope. A small forward speed is taken into account. The results of the new method are compared with that of the traditional method based on a formulation in the inertial coordinate system. When the traditional method applies, good agreement has been obtained.