基于粘聚单元的层冰-海洋平台碰撞数值模拟

Numerical simulation of layer ice-offshore platform collision based on cohesive element method

为研究海洋平台的抗冰性能,利用粘聚单元模型,构建层冰与半潜式海洋平台碰撞的有限元模型进行数值模拟,研究碰撞过程的冰力、结构吸能变化。随后进行粘聚单元参数敏感性分析,研究粘聚单元断裂能量释放率与牵引力-位移准则(TSL)曲线形式的变化对冰力的影响。结果显示,采用粘聚单元法模拟计算得到的冰力值与经验公式计算得到的冰力值偏差仅为2.2%,较为吻合,验证了粘聚单元法模拟层冰与海洋结构物碰撞过程的准确性;立柱外板是碰撞过程中平台的主要耗能构件,吸能占比82.67%;冰力值随着断裂能量释放率的增大而增大,但不同形式的TSL曲线对冰力值的影响十分有限。

In order to study the anti-icing performance of the offshore platform,the finite element model of the collision between layer ice and semi-submersible offshore platform is constructed by using the cohesive element model for numerical simulation.The ice force and structural energy absorption changes during the collision process are analyzed.Subsequently,the sensitivity analysis of cohesive element parameters(the effect of fracture energy release rate and traction-separation law curve)on ice force is studied.The results show that the deviation between the ice force calculated by the cohesive element method and the one calculated by the empirical formula is only 2.2%,which verifies the accuracy of the cohesive element method in simulating the collision process between layer ice and marine structures.The outer plate of the column is the main energy consuming component of the platform during the collision,and the energy absorption accounts for 82.67%.The ice force value increases with the increase of fracture energy release rate,but the influence of different forms of TSL curve on the ice force value is very limited.