基于黏聚单元法的冰-柱碰撞流固耦合计算方法研究

Fluid-structure interaction calculation method for ice-column collision based on cohesive element method

在采用黏聚单元法模拟海洋结构物与海冰的相互作用过程中,大多未考虑水的作用,与实际应用场景不符。基于LS-DYNA有限元软件,构建两种不同厚度的黏聚单元冰模型,采用S-ALE流固耦合方法,对圆柱体直立结构与层冰碰撞进行了数值模拟,研究了碰撞过程中层冰的破坏模式及柱体所受冰载荷,数值模拟结果与实际观测现象相吻合。随后分析了流场网格大小对耦合效果及冰载荷的影响。结果表明:柱体所受冰载荷与流场网格呈正相关,当流场网格为冰体单元的2倍时,计算时间及耦合效果最佳。

In the process of using cohesive element method to simulate ocean structure and sea ice interaction,the effect of water is not considered,which is inconsistent with the truth.Based on LS-DYNA finite element software,two different thicknesses of adhesive element ice models were constructed.By means of S-ALE fluid-solid coupling method,a numerical simulation of cylinder upright structure colliding with layer ice was carried out.The destruction mode of ice in the middle of the collision process and the ice load of the column were studied.The numerical simulation results coincided with the actual observations.Then the effect of mesh size on coupling effect and ice load was analyzed.The results show that the ice load of the cylinder is positively correlated with the flow field mesh.When the flow field mesh is twice as big as the ice unit,the calculation time and coupling effect are optimal.