Because a moored ship can be drifted and stranded when a mooring chain is broken due to a high wave, it is important to predict the movement of a moored floating object under action of such a high wave. Some of numerical prediction has been conducted, however, there is no model to simulate a floating object appropriately under a high wave. Therefore, in this study, a simulation model based on a particle method is developed.
When a mooring chain is broken due to a large-scale tsunami or a high wave, a moored ship can be drifted and stranded. The mooring system, which has been researched before (ex. Takayama et al., 1979), is one of the important research themes because, especially, a large-scale floating structure like a floating airport has attracted attention in late years. The numerical simulation is required for the rational design of a floating body, however, in a popular method to predict the motion of floating body, only a linear wave can be treated. A numerical model for tracking a floating body in a nonlinear wave had been developed by Ikeno (2000) and Mizutani et al. (2004), however, there is no numerical model applied in a high wave which causes strong wave force to break a mooring chain. The reason is difficulty in calculating the interaction between a floating body and fluid around water surface accurately in a previous numerical method. Especially in a high wave such as a ship is dashed blue wave. Therefore, in this study, a model for tracking of a moored floating body by using a particle method which is applicable for a violent water surface change is developed. In a particle method, because it is easy to treat a movable object, numerical analyses on a free floating body had already been carried out by Koshizuka et al.(1998), Sueyoshi et al.(2003) and Gotoh and Ikari(2007), however, there is no example of simulation for tracking of a floating body bound by a mooring chain based on a particle method.
