Abstract: The influence of the side wall effect on the ship motion should be taken into account to predict the motion of the ship in the restricted waters, such as a narrow channel or a canal. The side wall effect has been considered by introducing the green function of channel free surface. The green function of the side wall with free surface is then approached by Chebyshev polynomial to perform the efficient and high accurate calculations. The results calculated in the current study are compared with which is calculated by the commercial software. The artificial numerical damping is adopted for the free surface in order to address the numerical resonance phenomenon of the free surface during the numerical calculation, ensuring that the motion of the floating body and the calculated elevation of the free surface are more accordant with the actual conditions.

Key words: restricted water, green functionof side wall, numerical damping, Chebyshev approximation

摘要： 当预报船体在狭窄航道或运河等限制水域运动时,需要考虑池壁效应对运动的影响。通过引入自由面池壁格林函数来考虑池壁效应,并通过切比雪夫多项式对其进行逼近,完成了自由面池壁格林函数的高效和高精度计算。文章通过算例与商业软件进行对比,并给出结果。为解决计算过程中存在的自由面的数值共振问题,通过在自由面施加人工数值阻尼,以保证浮体运动和自由面升高计算结果更符合实际情况。

关键词: 限制水域, 池壁格林函数, 数值阻尼, 切比雪夫逼近