Abstract: When navigating in coastal areas, a ship may collide with a coastal bank, resulting in grounding. This issue involves interactions among the wave, the ship, and the coastal bank, with the key aspect being the contact between the ship and the bank. To solve this problem, a smoothed particle hydrodynamics (SPH) method is employed to simulate wave motion, wave-ship interaction, and wave-bank interaction. A discrete element method (DEM) is used to handle the interaction between the ship and the bank. Accordingly, a coupled SPH-DEM approach is established to study ship grounding. Numerical analysis is conducted for a bank with a 1:10 gentle slope under three wave periods, focusing on ship motion responses of pitch, surge, heave, and contact forces between the ship and the bank. The results show that under short-wave-period conditions, the ship remains grounded on the bank with small motion responses. Under the long-wave-period condition, the ship lifts off the bank and floats freely, with significantly increased motion responses. Regarding the contact forces between the ship and the bank, the vertical components are significantly larger than the horizontal components. In the early stage of grounding, the vertical components of the contact forces reach their peak values, accounting for up to 65.52% of the ship's gravity for all test cases. In the stable stage, the vertical components account for 32.84% and 41.89% of the ship's gravity for the two short-wave-period cases, and decrease to 0% for the long-wave-period case as the vessel is no longer grounded.

Key words: grounding, gentle-slope bank, coupled dynamics, SPH-DEM

摘要： 船舶沿岸航行时,易与岸滩碰撞导致搁浅事故。研究船舶搁浅过程,涉及波浪-船舶、波浪-岸滩、船舶-岸滩的相互作用,其中船舶与岸滩的接触作用是表征船舶搁浅动力学特性的关键。该文基于光滑粒子水动力学（smoothed particle hydrodynamics,SPH）方法求解波浪运动、波浪-船舶与波浪-岸滩相互作用,基于离散单元法（discrete element method,DEM）求解船舶-岸滩相互作用,建立了可用于研究船舶搁浅问题的SPH-DEM耦合方法。针对斜度为1:10的典型缓坡岸滩与3种波浪周期,计算分析了船舶纵摇、纵荡、垂荡运动响应,以及船舶-岸滩接触力。研究结果表明：在较短波浪周期条件下,船舶保持搁浅状态,其运动响应受岸滩边界限制,幅值均较小;在较长波浪周期条件下,船舶会脱离岸滩自由漂浮,运动响应幅值显著增大。搁浅时,船舶所受岸滩接触力的垂直分量远大于水平分量;搁浅初期阶段,在3种波浪周期工况下,船舶所受岸滩接触力垂直分量均达到极值,最大值可达船舶自重的65.52%;稳定阶段,在2种短波浪周期工况下,岸滩接触力垂直分量分别可达自重的32.84%与41.89%,而长波浪周期工况因船舶脱离搁浅,该值降为0。

关键词: 搁浅, 缓坡岸滩, 耦合动力学, SPH-DEM