Numerical investigation on the water entry of curved wedge-shaped sections into waves

Abstract

The water entry of structures with curved boundaries into waves can be frequently observed in actual operations as they are often exposed to harsh wave conditions. To investigate the problem, a numerical model which can simulate the water entry of complex objects into waves is developed in this paper. Under the framework of Cartesian grid, Volume of Fluid method combined with Piecewise Linear Interface Calculation (VOF-PLIC) are used to capture free surface. In addition, Volume of Solid Based Immersed Boundary Method (VOS-IB) is adopted to treat the body condition. Relaxation zones are applied to generate and absorb waves. After a careful validation, five curvatures and three entry locations are selected to investigate the influences of curvature and entry locations on slamming characteristics. Discoveries can be generally summarized as follows: 1) The arriving moment of force peak is not sensitive to the entry location, but is sensitive to the shape of curvatures because of its significant influence on flow separation. 2) The magnitude of force peak is always the smallest at wave peak, followed by calm water and wave trough, regardless of the shape of curvature. 3) The relative magnitude of the pressure on the left and right sides of body surface is influenced not only by the curvature but also by the entry location, and it changes during the water entry process. 4) Sequence of flow separation on the left and right sides of the body is determined by entry location, not by the curvature.