New insight into the generation of ship bow waves

The generation of ship bow waves is studied within the framework of potenti al flow theory. Assuming the ship bow to be slender, or thin, a pattern of the flow is derived using the method of matched asymptotic expansions. This method leads to the determination of three different zones in which three asymptotic expansions are performed and marched. To first order with respec t to the slenderness parameter, the near-field how appears to be two-dimens ional in each transverse plane along the bow. However, it is demonstrated t hat three-dimensional effects are important in front of the ship and must b e taken into account in the composite solution. This leads to a three-dimen sional correction to be added to the two-dimensional solution along the shi p. The asymptotic approach is then applied to explain the structure of the bow flow in connection with experimental observations and numerical simulat ions.