Numerical solution for a ship-wave problem in a two-layer fluid using a double-model linearised interface condition

摘要

Ship performance in shallow water where the rigid bottom is covered by a mud layer is a crucial topic to be investigated. In such muddy areas, a two-layer fluid is stratified according to the properties of the sediments. The water-mud interface behaves similar to a sheet on which the internal waves propagate after the ship's passage. Therefore, for safe navigation, it is necessary to clearly understand the influence of the internal waves on the ship's hydrodynamic force characteristics. In this study, the steady wave-making problem of a ship in a two-layer fluid was solved using the Rankine source panelmethod. The boundary value problem was formulated using a newly proposed double-model linearised interface condition. After the present method was validated via a comparison with results of a Wigley hull solved by the author's existing method, it was applied to solve the ship-wave problem of KVLCC2. The unique changes in wave-making resistance, sinkage and trim according to the ship's speed and two-layer fluid conditions were evaluated.