内孤立波作用下FPSO理论载荷预报

Theoretical Load Prediction of FPSO under the Action of Internal Solitary Waves

为解决FPSO在内孤立波作用下理论载荷预报的问题,基于两层流体系统中内孤立波KdV、eKdV、mKdV和MCC理论,结合已有的内孤立波与FPSO相互作用的大型密度分层水槽系列实验结果与Froude-Krylov公式,建立内孤立波作用下FPSO理论载荷预报模型。结果表明:内孤立波水平载荷可分为压差力与摩擦阻力,摩擦阻力约为压差力的1/3,摩擦力和压差力在时历上存在相位差;垂向载荷主要为压差力;摩擦阻力系数与上下层流体分层比和雷诺数有关,且呈指数关系,据此构建理论预报模型,预报结果与实验结果对比一致性较好。

To solve the problem of theoretical load prediction of FPSO under the action of internal solitary waves,a theoretical load prediction model for FPSO under the action of internal solitary waves is established based on the KdV,eKdV,mKdV and MCC theories of internal solitary waves in a two-layer fluid system,combined with the existing experimental results of large-scale density layered water tank series on the interaction between internal solitary waves and FPSO and the Froude-Krylov formula.The results show that the horizontal load of internal solitary waves can be divided into pressure difference force and frictional resistance,with frictional resistance being about one-third of the pressure difference force.There is a phase difference between frictional force and pressure difference force in the time domain;The vertical load mainly consists of differential pressure force;The friction resistance coefficient is related to the stratification ratio and Reynolds number of the upper and lower fluid layers,and exhibits an exponential relationship.Based on this,a theoretical prediction model is constructed,and the predicted results agree with the experimental results.