水下管汇阻力系数和附加质量系数的CFD计算

深水管汇下放是水下生产系统安全工作的关键技术之一。针对深水管汇下放时受到的水动力,即阻尼力和附加质量力进行分析研究。通过CFD软件Fluent建立管汇水动力计算模型和水下作业环境中绕流场的模型,计算管汇下放3个方向阻尼力及其阻力系数; 利用动网格技术模拟管汇在流场中的加速运动,求得管汇在水中的变速运动带动周围的流体一起做不定常运动所形成的附加质量系数。通过与现有DNV经验数据对比,计算结果误差较小,从而验证了此计算方法的正确性,为船-缆-体的耦合分析计算及下放安装的仿真控制提供参考。

CFD Based Drag Coefficient and Additional Mass Coefficient Calculation of Subsea Manifold

The installation of subsea manifold is one of the key technologies for the safety of underwater production systems.In this paper,the drag force and the additional mass force of hydrodynamics are analyzed.The CFD software Fluent is used to establish the model of manifold water and simulate the calculation of flow around the underwater operating environment.The three directions of drag force and its drag force coefficient are calculated.The use of dynamic grid technology to simulate the manifold's accelerated movement in the flow field,to consider the manifold in the water in the variable speed drive around the fluid together to do with the constant movement of the formation of additional mass coefficient.By comparing with the empirical data of DNV,the error of the calculation result is small,which verifies the correctness of the calculation method and lays the foundation for the coupling analysis of ship-cable-body and the simulation control of the decentralized installation.