论文标题
由于散射在破碎的浮球场中，波团衰减的非线性模拟
Nonlinear simulation of wave group attenuation due to scattering in broken floe fields
论文作者
论文摘要
进行直接相位分辨的模拟，以研究碎片海冰中非线性海浪的繁殖和散射。数值模型求解与非线性电位流与冰盖的非线性薄板表示的非线性电势流的全职方程，并忽略了耗散过程。鉴于应用在边缘冰区的样带沿横断面的衰减的应用，考虑了在深水上的二维设置。将空间变化的重量分配给表面压力，以便可以在物理结构域中直接指定冰浮止的不规则分布。对于各种波动机制和浮动配置，计算冰场上的局部波谱，然后拟合最小二乘以提取空间衰减速率随波频频率的函数。发现频率的一般增加与线性理论的典型预测一致。但是，还观察到一定频率周围的非单调行为，尤其是在高度碎片冰盖的情况下。与现场数据的比较表明，该结果与北极海洋实验报告的滚动现象非常相似。非线性互动在滚动开发中所起的关键作用被突出显示。
Direct phase-resolved simulations are performed to investigate the propagation and scattering of nonlinear ocean waves in fragmented sea ice. The numerical model solves the full time-dependent equations for nonlinear potential flow coupled with a nonlinear thin-plate representation of the ice cover, and neglects dissipative processes. The two-dimensional setting with incident wave groups on deep water is considered, in view of applications to wave attenuation along transects of the marginal ice zone. A spatially-varying weight is assigned to the surface pressure so that irregular distributions of ice floes can be directly specified in the physical domain. For various wave regimes and floe configurations, a local wave spectrum across the ice field is computed and then least-squares fitted to extract a spatial attenuation rate as a function of wave frequency. A general increase with frequency is found, consistent with typical predictions from linear theory. However, a non-monotonic behavior around a certain frequency is also observed, especially in cases with a highly fragmented ice cover. Comparison to field data shows that this result closely resembles the roll-over phenomenon as reported from Arctic Ocean experiments. The key role played by nonlinear interactions in the roll-over development is highlighted.
