Nonlinear Wave-Ice-Interaction

非线性波冰相互作用

• 批准号: 407532845
• 负责人: Dr.-Ing. Marco Klein
• 金额: --
• 依托单位: Institut für Konstruktion und Festigkeit von Schiffen
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407532845?language=en
• 关键词: Nonlinear; Wave; Ice; Interaction

This research project addresses the fundamental question of nonlinear wave-ice interaction under solid ice focusing on nonlinear wave propagation and dispersion of waves. The objective is to verify if nonlinearity takes place under solid ice. Thereby, nonlinear wave-ice interaction as well as the impact of the solid ice characteristics on this interaction will be investigated. The investigations comprise numerical simulations accompanied by experiments. Special nonlinear wave groups and typical swell conditions in the vicinity of ice covers will be investigated. Envelope soliton and Peregrine breather solutions will be applied representing exact solutions of the Nonlinear Schrödinger Equation (NLSE). The application of such nonlinear wave groups are predestined for the objective of this research proposal – verification that nonlinearity takes place under solid ice – as these wave groups’ can only be observed within experiments if nonlinear wave-wave interaction takes place. This denotes that the existence of such wave groups in the ice tank is the direct proof.The goal of the experiments is to verify experimentally for the first time that nonlinearity takes place under solid ice resulting in stable wave groups as well as exaggerated wave amplitudes. With the help of the Peregrine breather it shall be shown that modulation instability will lead to an exaggerated wave height far away from the edge of the solid ice. In addition, and based on numerical simulations, selected swell cases of special interest regarding nonlinear phenomena will be reproduced in the ice tank. Besides focusing on nonlinear wave effects under solid ice, the effect of solid ice on the wave length and wave energy propagation, respectively, will also be investigated, i.e. the change of wave length due to the sudden presence of solid ice will be measured and compared to theoretical findings.The experiments will be conducted in two different ice types. One will be seeded model ice, where properties of waves and ice will be scaled according to the state of the art, i.e. geometrically scaled while maintaining Froude and Cauchy similitude, where damping properties might be exaggerated compared to naturally grown ice. The second ice type will be regular, naturally grown ice in the basin, where the ice strength might be high, but the elastic deformation and related restoring forces as well as the damping of waves is considered to be more similar to sea ice. The objective here is to assess possible differences between the two ice types and to evaluate whether the state of the art model ice does even allow a scaling of the problem following the current state of the art.

本研究项目主要研究固体冰下非线性波-冰相互作用的基本问题，重点研究波的非线性传播和频散。其目的是验证在固体冰下是否发生了非线性。在此基础上，研究了波浪与冰的非线性相互作用以及固体冰的特性对这种相互作用的影响。研究包括数值模拟和实验。将研究冰盖附近特殊的非线性波群和典型的涌浪条件。包络孤子解和游动呼吸子解将被用来表示非线性薛定谔方程(NLSE)的精确解。这种非线性波群的应用注定是为了本研究提案的目的--验证在固体冰下发生非线性--因为只有在发生非线性波-波相互作用的情况下，才能在实验中观察到这些波群。实验的目的是首次从实验上验证固体冰下发生的非线性现象，从而产生稳定的波群和夸大的波幅。在百富勤呼吸器的帮助下，应表明调制不稳定性将导致远离固体冰边缘的夸大波高。此外，在数值模拟的基础上，选定的与非线性现象特别相关的涌浪案例将在冰箱中重现。除了研究固体冰下的非线性波动效应外，还将分别研究固体冰对波长和波能传播的影响，即测量由于固体冰的突然存在而引起的波长变化，并与理论结果进行比较。一种是种子模型冰，其中波浪和冰的属性将根据最新技术进行缩放，即在保持弗劳德和柯西相似的同时进行几何缩放，与自然生长的冰相比，其中的阻尼属性可能会被夸大。第二种类型的冰将是盆地中自然生长的规则冰，那里的冰强度可能很高，但弹性变形和相关的恢复力以及波浪的阻尼被认为更类似于海冰。这里的目的是评估两种冰类型之间的可能差异，并评估最先进的模型冰是否甚至允许根据当前的技术状态对问题进行缩放。