海冰重叠动力条件分析

Analysis on dynamic conditions of ice rafting

由于重叠冰厚度较大,给冰区海洋运输以及海洋生产作业等带来较大影响,为了得到科学客观的重叠冰厚度,需要对重叠冰的形成条件进行深入研究。利用理论分析和数值模拟方法,分析了波浪、风和流对渤海海冰重叠的影响。通过理论计算分析发现,波浪是导致海冰断裂的主要因素;采用离散元方法对海冰重叠过程进行了数值模拟,模拟结果表明海冰在外界动力作用下,海冰初始发生屈曲变形断裂,随后产生重叠。综合分析表明,海冰在同时具备波浪的垂向波动作用以及风或流水平作用力下,冰层比较容易发生重叠,波浪对海冰重叠的作用不可忽略,海冰的重叠长度取决于风和流作用的大小,其作用力越大,重叠长度越大。

The rafted ice can prominently affect navigation and platform production for its rather great thickness.Studying its forming condition is important in analyzing the reliability of ice design parameters of offshore structure.Theoretical analysis and numerical simulation have been applied to discuss the effect of wave,current and wind on the ice rafting.The Theoretical analysis results show that wave is the key factor for ice fracture.The process of ice rafting is simulated by using the discrete element method,and the simulated results show that the distortion and flexure breakage are happened initially and rafting followed then.The synthesis analysis results show that the ice is easily rafted under the joint action of wave,current and wind,and the action of wave can′t be ignored.Moreover,the rafted ice length increases with the increasing force of ocean current and wind.