密度层化流体波动场中小尺度水平圆柱体受力模拟

Simulation of Wave Force on Small-Scale Horizontal Cylinder in Density Stratification Sea Water Movement

随着海上采油事业发展,海底输油管线受力分析得到了广泛重视.抛弃刚盖假设,模拟了密度分层流中内波与表面波耦合场,采用Morison公式计算了不同深度处水平小尺度圆柱受到的内波和表面波联合作用力.数值结果表明:表面波对内波的影响是不可忽略的;迁移加速度相对当地加速度是一小量;内波场产生的水平波浪力幅值较小,只在水平方向引入高波数振型;内波对垂向波浪力的影响较大;惯性力远大于拖曳力.这些为海底管线受力分析提供了理论基础.

With the rapid development of offshore oil extraction, the wave force acting on the seabed pipe laying arouses wide attention. By abandoning the assumption of rigid free surface, the coupling field of surface wave and internal wave was simulated by the density stratification model. The joint wave force acting on the small-scale horizontal cylinder at different depth was obtained by Morison equation. Numerical results show that the surface wave has strong influence on the internal wave;the convective acceleration is much smaller comparing to the local acceleration; the horizontal wave force caused by the internal wave introduces the high frequency oscillation only, and its amplitude is rather small; the effect of internal wave has strong influence on the vertical surface wave force; the inertial force is far larger than drag force. All these lay a basis for analyzing the wave force acting on the seabed oioe.