【摘要】 冰脊对极地船舶及海洋工程结构的冰载荷设计及冰区安全运行具有重要的影响，其几何形态是重要的考虑因素。为研究冰脊的几何形态，本文基于Voronoi切割算法构造扩展多面体海冰单元，并使其相互冻结形成平整冰；采用离散单元法模拟海冰在相向运动时挤压形成冰脊的动力过程，统计分析脊帆高度、龙骨宽度、龙骨深度、龙骨水平倾角等主要几何参数，并确定这些几何参数间的对应关系。将离散元模拟结果同冰脊现场观测资料对比分析以验证扩展多面体离散元方法模拟冰脊形成过程的可行性。在此基础上讨论冰厚、冰速、海冰强度等因素对冰脊形态的影响。本文采用离散元方法对冰脊形成过程及几何特性的数值分析可为深入开展冰脊的形成机理及其对船舶、海洋工程结构物的冰载荷分析提供参考依据。更多还原

【Abstract】 Ice ridges have a vital effect on the design of ice loads and the safe operation for polar ships and ocean engineering structures in ice-covered regions. The geometric shape of ice ridge is an important factor. To study the geometric morphology of ice ridges, this paper constructs the dilated polyhedral sea ice elements based on Voronoi tessellation algorithm and freezes them to form flat ice. The dynamic process of sea ice squeezing to form ice ridges in phase motion is simulated by using discrete element method. The main geometric parameters such as sail height, keel width, keel depth, keel angle are statistically analyzed, and the correspondence between these geometric parameters is determined. The DEM simulation result is compared with the ice ridge field observation data to verify the feasibility of using the dilated polyhedron discrete element method to simulate the ice ridge generation process. On this basis, the effects of ice thickness, ice velocity, sea ice strength and other factors on ice ridge morphology are discussed. The numerical analysis of the present study can provide a reference basis for the further development of the formation mechanism of ice ridges and their analysis of ice loads of ship and ocean engineering structures.更多还原