Numerical tools of this type are scarce and with some limitations. Most of them use linear theory to describe the wave-floating structure interaction and a very simplified geometry of the port. However, an accurate representation of the port geometry is important to take into account the evanescent modes close to the ship and to better describe the wave field acting on the ship. Several authors have developed methods to solve this problem using increasingly complex and sophisticated models (Sawaragi & Kubo, 1982, Sawaragi et al., 1989; Takagi et al., 1993; Sakakibara & Kubo, 1997, Bingham, 2000, Wenneker et al., 2006 Wenneker & Molen, 2008).