In this paper, the interactions between extreme waves and a vertical cylinder are investigated through a 3-D two-phase flow model. The numerical model is verified and validated by experimental data. Then, two factors are considered, the global wave steepness and the frequency bandwidth of the wave groups, in the studies of the in-line wave forces and the wave run-up around a cylinder. It is found that both the in-line wave forces and the wave run-up are remarkably increased with the increase of the global wave steepness, whereas the effect of the frequency bandwidth on the in-line wave forces is relatively weak in comparison with its effect on the wave run-up. The minimum and maximum wave run-ups are located in the directions of 22.5° and 180° with respect to the direction of the incident waves, respectively. Additionally, a new empirical formula is proposed for predicting the in-line wave forces by using only the free surface elevations around the cylinder. The results of the formula agree well with the simulation results.

在本文中，通过3-D两相流模型研究了极端波与垂直圆柱之间的相互作用。通过实验数据对数值模型进行了验证。然后，在研究直列波浪力和圆柱体绕波时，要考虑两个因素，即整体波陡度和波群的频率带宽。研究发现，随着整体波陡度的增加，轴向波力和波径都显着增加，而与之相比，频率带宽对轴向波力的影响相对较弱。对波浪上升的影响。最小和最大波上升分别相对于入射波方向位于22.5°和180°方向。另外，提出了一个新的经验公式，通过仅使用圆柱体周围的自由表面高程来预测轴向波动力。公式的结果与仿真结果吻合良好。