碎冰水域定常流中海洋平台的载荷特性研究

Load Mechanics on Offshore Platform Operating in Broken Ice Field with Uniform Current

由于作业环境的特殊性,极地海洋平台在整个服役期内易同时遭受冰碰撞载荷和流体动力载荷。在运动过程中,层冰易发生断裂,形成小尺度碎冰,它们对平台水动力性能与结构安全构成威胁。论文建立开敞水域海洋平台计算流体动力学(CFD)数值模型,引入离散元(DEM)模拟碎冰及其与海洋平台之间的碰撞,探索海洋平台所受的碎冰载荷随流速及碎冰密集度的变化规律。结果表明,海洋平台所受的碎冰载荷随着流速和碎冰密集度的增加而增大,但当流速超过某一特征值时,碎冰载荷随着流速的增加呈减小趋势。

Due to the special environment of arctic, there will be both ice and hydrodynamic loads acting on an offshore platform during its operation. This makes a great threaten to the safety of the structure and overall performance of the platform. In the melting process of sea ice, large ice sheet will be broken into small scale ice floes. In order to understand the characteristics of load mechanics on an offshore platform operating in broken ice field with uniform current, the discrete element method is introduced for ice floes and their collisions with the platform. The traditional computational model for fully open water combined with it is then used to predict the coupled motions of the platform, fluid, and ice floes. Numerical results are provided to show the variations of the ice and fluid load against the speed of the current and density of the ice floes. It is found that the ice load increases with the increase of current speed and ice concentrations generally.However, when the current speed exceeds a certain value, the ice load will be decreased.