Abstract: A 2D process of a plane-movement object (boat) moving around a static one (bridge pier) is investigated by combining incompressible Navier-Stokes equations with immersed boundary methods. The fluid’s effects on the boat and the boat’s track are mainly studied. The results show that the drag and lift curve lines oscillate with finite amplitudes at the beginning and approach to periodic micro vibrations soon. The boat rotates clockwisely at first, and then the speed becomes smaller and smaller, and later it changes to an anticlockwise rotation. Finally the boat’s stern moves away from the pier, and it won’t impact with the pier. The boat’s trajectory agrees with that from the real boat experiments.

Key words: incompressible Navier-Stokes equations, immersed boundary method, fluid-structure interaction, secondary impact, ship-bridge pier collision

摘要： 将不可压缩Navier-Stokes方程与浸入边界法相结合, 研究在流体中平面运动的物体(船)绕另一个静止物体(桥墩)的二维运动过程, 分析船所受到的流体阻力、升力以及受流体作用后船的运动轨迹。结果表明在船绕着桥墩运动的初期, 升力和阻力曲线出现有限振幅的起伏现象, 不久, 船的升力和阻力系数逐渐趋向稳定, 做周期性小幅振荡。船的顺时针方向角速度受水流作用逐渐变小, 然后变为逆时针方向。最后船的尾部远离桥墩, 表明不会与桥墩二次碰撞。船的运行轨迹与实船实验的结果非常接近。

关键词: 不可压缩Navier-Stokes方程, 浸入边界法, 流体?结构相互作用, 二次碰撞, 船撞桥