Development of a viscoelastic phase field model for fracture processes with application to ice dynamics

开发适用于冰动力学的断裂过程粘弹性相场模型

• 批准号: 501994052
• 负责人: Professor Dr.-Ing. Ralf Müller
• 金额: --
• 依托单位: Fachgebiet Kontinuumsmechanik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/501994052?language=en
• 关键词: Development; viscoelastic; phase; field; model

The propagation of cracks in floating ice tongues results in the break-off of large icebergs. This process is referred to as calving. The understanding of calving is of great importance for the judgement of the consequences of climate warming. An increased calving leads to an accelerated flow of meteoric ice into the oceans, which is followed by a sea level rise. To model complex crack propagation phenomena in floating ice tongues a viscoelastic constitutive law of ice based on a non-linear Maxwell model is combined with a fracture mechanical phase field. The modeling is pursued in successive steps, resulting in geometrically and constitutively non-linear Lagrangian description of the material flow in conjunction with a fracture phase field. The model is implemented in the finite element toolbox FEniCS and allows for the simulation of complex crack patterns in floating ice tongues. The creation, propagation, arrest, and branching of cracks can be considered. As an application scenario the Nioghalfjerdsbrae glacier in Greenland is investigated.

浮冰舌裂缝的扩展导致了大型冰山的断裂。这个过程被称为产犊。了解冰裂对判断气候变暖的后果具有重要意义。冰裂的增加导致大气冰加速流入海洋，随之而来的是海平面上升。为了模拟冰舌中复杂的裂纹扩展现象，将基于非线性Maxwell模型的冰的粘弹性本构律与断裂力学相场相结合。建模是在连续的步骤中进行的，导致材料流的几何和本构非线性的拉格朗日描述，并结合断裂相场。该模型在有限元工具箱FEniCS中实现，并允许模拟浮动冰舌中的复杂裂纹模式。可以考虑裂缝的产生、扩展、停止和分支。以格林兰Nioghalfjerdsbrae冰川为例进行了研究。