基于Fluent的内孤立波数值模拟及其作用下顶张力立管动力响应分析

Numerical Simulation of Internal Solitary Waves Based on Fluent and Dynamic Response Analysis of Top Tension Risers

摘要: 本文基于Fluent软件，建立具有多种设计振幅的内孤立波数值水槽，通过质量源造波方法实现对内孤立波的模拟，与物理实验结果及理论结果进行对比分析，利用软件自带的监测功能在对大振幅内波进行模拟时获取波致流场数据，结合改进的Morison方程计算内孤立波对顶张力立管的作用，基于欧拉–伯努利梁模型利用有限元法分析其动力响应。结果表明，本文采用的质量源造波方法下的模拟结果，与实验及理论吻合较好，在大振幅内孤立波作用下，立管位于上层流体中的部分所受到的来自内孤立波的水平作用力相比于位于下层流体中的部分大了许多，而在内孤立波作用下的顶张力立管发生的变形和产生的应力都很大，在波谷到达立管时应力与变形达到最大。

Abstract: In this paper, a numerical flume of internal solitary wave with various design amplitudes is estab-lished based on the Fluent software. The internal solitary wave is simulated by mass source wave-generating method and the simulation results are compared with the physical experiment and theoretical results. The data of wave-induced flow field are obtained by monitoring function of the software. Combined with the modified Morison equation, the effect of internal solitary wave on the top tension riser is calculated, and its dynamic response is analyzed by finite element method. The results indicate that the mass source wave-generating method adopted in this paper is in good agreement with the experimental and theoretical results. Under the large amplitude internal solitary wave, the horizontal force of internal solitary wave on the riser in the upper fluid is obviously greater than that on the riser in the lower fluid. The riser under the action of internal solitary wave will undergo large deformation and produce large stress. When the valley reaches the riser, the stress and deformation reach the maximum.