論文
沿岸における浅水航走波の伝播と変形
2001 年 13 巻 1 号 p. 131-140
詳細
2001 年 13 巻 1 号 p. 131-140
Ship waves in shallow water are greatly different from those in deep water. In the present paper, the numerical method of ship waves by Tanimoto et al. was applied to shallow open water in order to investigate the following points: 1) change of the patteｒｎ and the maximum wave height of ship waves in open water by water depth, 2) effect of the reflection from a vertical wall on ship waves, 3) propagation and transformation of ship waves on a coast with straight, parallel depth contours.
The change of wave patteｒｎ by water depth is similar to the one shown by Havelock . When the ship speed is critical or super-critical, however, bow waves ahead of the ship are split to several isolated waves as they propagate. The reflection at the vertical wall makes Mach-stem. Transformations due to shoaling and refraction occur when ship waves propagate on the sloping coast. The time profile of ship waves at very shallow water shows a leading long wave group and following short wave group as Kirkegaard et al. observed at Danish coast, when the ship speed is near-critical at the sailing depth.
