论文标题
提高海冰粘性塑料配方的数值准确性
Improving numerical accuracy for the viscous-plastic formulation of sea ice
论文作者
论文摘要
海冰动力学的准确建模对于预测环境变量至关重要,并且在诸如导航破冰船之类的应用中很重要。建模和模拟海冰动力学的研究正在进行中,基于Hibler在1979年引入的粘性塑料(VP)公式的最广泛接受的模型。由于其高度非线性的特征,该模型对计算求解器来说具有内在挑战性。特别是,海冰模拟通常与卫星观测明显不同。因此,这项研究的重点是提高VP海冰模型的数值准确性。由于在现有的数值模拟中观察到的不良收敛源于VP公式的非线性性质,因此本研究提出了使用著名的加权基本非振荡(WENO)方案(与经常使用的中心差异(CD)方案) - 用于VP Sea Ice模型中的空间衍生物。然后,我们开始数字证明WENO为平滑溶液产生高阶收敛性,并且它可以解决海冰盖的尖锐特征中的不连续性 - 使用CD方法是不可能的。最后,我们提出的框架集成了一种潜在的函数方法,该方法利用相位场方法自然地将冰厚度和冰块浓度的物理限制纳入传输方程,从而导致了修改的传输方程,其中包括附加的强迫项。我们的方法不需要后处理,从而避免了可能引入不连续性并对解决方案行为产生相应的负面影响。提供了数值实验来证明我们新方法的功效。
Accurate modeling of sea ice dynamics is critical for predicting environmental variables and is important in applications such as navigating ice breaker ships. Research for both modeling and simulating sea ice dynamics is ongoing, with the most widely accepted model based on the viscous-plastic (VP) formulation introduced by Hibler in 1979. Due to its highly nonlinear features, this model is intrinsically challenging for computational solvers. In particular, sea ice simulations often significantly differ from satellite observations. This study therefore focuses on improving the numerical accuracy of the VP sea ice model. Since the poor convergence observed in existing numerical simulations stems from the nonlinear nature of the VP formulation, this investigation proposes using the celebrated weighted essentially non-oscillatory (WENO) scheme -- as opposed to the frequently employed centered difference (CD) scheme -- for the spatial derivatives in the VP sea ice model. We then proceed to numerically demonstrate that WENO yields higher-order convergence for smooth solutions, and that furthermore it is able to resolve the discontinuities in the sharp features of sea ice covers -- something that is not possible using CD methods. Finally, our proposed framework integrates a potential function method that utilizes the phase field method to naturally incorporates the physical restrictions of ice thickness and ice concentration in transport equations, resulting in a modified transport equations which includes additional forcing terms. Our method does not require post-processing, thereby avoiding the possible introduction of discontinuities and corresponding negative impact on the solution behavior. Numerical experiments are provided to demonstrate the efficacy of our new methodology.