We model fully nonlinear free surface waves caused by a translating disturbance made of a pressure patch and/or a surface-piercing body (ship), within the framework of potential flow theory. The three-dimensional higher-order Boundary Element Model by Grilli et al. (2001) and Fochesato et al. (2004) is utilized with some recent extensions. In addition to the regular Eulerian-Lagrangian updating of the free surface geometry and potential, based on higher-order explicit Taylor series expansions, a pseudo-Lagrangian updating algorithm is developed to express and solve the problem in a coordinate system traveling at the instantaneous speed of the moving disturbance. This paper presents theoretical developments and applications illustrating both the accuracy and efficiency of the present method for a traveling pressure patch and an advancing Wigley hull. Based on numerical results, it is concluded that the present numerical approach, with a pseudo-Lagrangian updating and a higher-order BEM provides accurate and efficient results.
Despite some recent progress, the numerical modeling of wave generation and propagation around ocean going ships, and corresponding wave resistance, still poses significant technical problems, particularly for high-speed Surface Effect Ships (SES) such as the recently proposed Harley FastShip, for which nonlinearities in the generated wave field may be large.
Surface vessels generate so-called Kelvin wave patterns, that can radiate far downstream of the vessel. The history of wave analysis around moving ships can be traced back to Michell, Havelock, Wehausen, and other precursors of naval hydrodynamics. Most of these classical works deal with some aspects of and definition of "wave resistance", or the theoretical prediction of wave resistance of simple bodies, or ship hulls having simplified analytic lines (Wehausen, 1973). A review of analytical representations of ship waves can be found in Noblesse (2000).
