冰载荷作用下半潜式平台动力定位能力分析

为分析半潜式平台在冰和风浪流共同作用下的动力定位能力,使用有限元软件LS-DYNA建立冰载荷数值模型,以半潜式平台为对象,得到不同迎冰角下的冰力时程曲线。基于自主开发的动力定位能力分析程序,将冰载荷纳入环境载荷进行计算并绘制平台在碎冰区的动力定位能力曲线。观察平台在工作海况下的作业窗口,发现碎冰场的冰载荷对平台的动力定位能力有较大影响,尤其当艏向在30°,60°]时影响最明显。结合推进器失效工况对平台动力定位能力进行评估,提出平台遭遇碎冰场时的动力定位方案和对推进系统设计的建议。

Dynamic Positioning Capability Analysis of Semi-Submersible Platform Under Ice Load

In order to analyze the Dynamic Positioning Capability(DPCap) of the semi-submersible platform under the combined action of ice, wind, wave and current, the finite element software LS-DYNA is used to build a numerical model of ice load, and the ice force time course curves are obtained for different ice-welcoming angles with semi-submersible platform as an object.Based on the self-developed DPCap analysis program, the ice load is incorporated into the environmental load, the DPCap of the platform in broken ice area is calculated and the DPCap curves are drawn.The working window of the platform in operating sea conditions is observed, and it is found that the ice loads of the broken ice area are of great influence on the DPCap of the semi-submersible platform, and the impact is most obvious when heading in30°,60°]. The DPCap of the semi-submersible platform is evaluated in combination with the failure condition of the propeller, and the DP scheme when the platform encounters the broken ice area and the suggestions for the design of the propulsion system are proposed.