基于Orcaflex的水下应急封井装置安全入水仿真

Orcaflex-Based Simulation on Safe Entering Water of Subsea Emergency Capping Stacks

为确保3 000 m水深水下应急封井装置的安全入水,基于Orcaflex对3 000 m水深水下应急封井装置下放入水过程进行了模拟仿真。研究了不同因素对绞车缆绳最大受力和装置运动响应的影响,并将Orcaflex模拟结果与理论公式计算结果进行对比,得到如下结论:绞车缆绳最大受力(1 538. 5 kN)发生在水下应急封井装置在空气中的下放过程,而水下应急封井装置最大运动响应发生在入水前后;当波浪力垂直于船身方向时,绞车缆绳受力最大,水下应急封井装置运动响应最大,而其余波浪方向角对其影响较小,因此在进行水下应急封井装置下放入水操作时,最好让工程船的方位角沿着波浪方向角;绞车下放速度对绞车缆绳最大受力和水下应急封井装置运动响应影响较大,当下放速度为0. 3 m/s时,绞车缆绳最大受力为1 657. 4 kN,同时水下应急封井装置运动响应也增大,绞车缆绳属性对其影响较小;仿真结果比Chuang公式和Chen公式计算结果更接近理论公式计算结果。研究结果可对水下应急封井装置快速安全地安装和回收提供指导。

To ensure the safe water entering of the 3 000 m subsea emergency capping stacks, the water entering process of the 3 000 m subsea emergency capping stacks is simulated based on Orcaflex. The effects of different factors on the maximum force of the winch cable and the motion response of the device are studied. The Orcaflex simulation results are compared with the theoretical calculation results to present the following results: the maximum force of the winch cable (1 538. 5 kN) is observed when the device is in the air. The maximum motion response of the device observed before and after entering water. When the wave force direction is perpendicular to the ship direction ,the winch cable has the maximum stress and the device has the largest motion response. The remaining wave direction angles show less influence. Therefore, during entering water operation, it is better to position the ship along the wave direction angle. The winch lowering speed has a great influence on the maximum force on the winch cable and the motion response of the device. When the lowering speed is 0. 3 m/s, the maximum force of the winch cable is 1 657. 4 kN, and the motion response of the device is also increased. The winch cable property shows a little influence. The simulation results are closer to the theoretical calculation results than that of the Chuang formula and the Chen formula.