Performance of Adaptive Unstructured Mesh Modelling in Idealized Advection Cases over Steep Terrains
Performance of Adaptive Unstructured Mesh Modelling in Idealized Advection Cases over Steep Terrains
复制标题
陡峭地形理想化平流情况下自适应非结构化网格建模的性能
DOI：
10.3390/atmos9110444
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发表时间：
2018-11
期刊：
影响因子：
2.9
通讯作者：
Xiao Hang
中科院分区：
文献类型：
--
作者：
Li Jinxi;Zheng Jie;Zhu Jiang;Fang Fangxin;Pain Christopher C;Steppeler Juergen;Navon Ionel M;Xiao Hang
平流误差在基本地形跟随 (TF) 坐标中很常见。人们提出了多种方法来减少平流误差，包括混合TF坐标和平滑垂直层。平流误差受速度场方向和地形复杂程度的影响。在这项研究中，采用非结构化自适应网格和不连续伽辽金有限元方法来减少陡峭地形上的平流误差。为了测试自适应网格的能力，进行了五个二维 (2D) 理想化测试。然后，将自适应网格的结果与切单元网格和 TF 网格的结果进行比较。结果表明，与切割单元和 TF 网格相比，使用自适应网格可将平流误差减少一到两个数量级，无论速度方向或地形复杂性如何变化。此外，自适应网格可以减少示踪剂沿地形表面切向移动时的平流误差，并允许在不产生严重分散的情况下表示地形。最后对计算成本进行了分析。为了达到给定的标记标准水平，与切割单元和TF网格相比，自适应网格需要更少的节点、更小的最小网格尺寸、更少的运行时间以及用于解析示踪剂和每个波长的节点数之间的比例更低，从而降低了计算成本。
Advection errors are common in basic terrain-following (TF) coordinates. Numerous methods, including the hybrid TF coordinate and smoothing vertical layers, have been proposed to reduce the advection errors. Advection errors are affected by the directions of velocity fields and the complexity of the terrain. In this study, an unstructured adaptive mesh together with the discontinuous Galerkin finite element method is employed to reduce advection errors over steep terrains. To test the capability of adaptive meshes, five two-dimensional (2D) idealized tests are conducted. Then, the results of adaptive meshes are compared with those of cut-cell and TF meshes. The results show that using adaptive meshes reduces the advection errors by one to two orders of magnitude compared to the cut-cell and TF meshes regardless of variations in velocity directions or terrain complexity. Furthermore, adaptive meshes can reduce the advection errors when the tracer moves tangentially along the terrain surface and allows the terrain to be represented without incurring in severe dispersion. Finally, the computational cost is analyzed. To achieve a given tagging criterion level, the adaptive mesh requires fewer nodes, smaller minimum mesh sizes, less runtime and lower proportion between the node numbers used for resolving the tracer and each wavelength than cut-cell and TF meshes, thus reducing the computational costs.
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影响因子：
3.2
作者：
J. Steppeler;J. Klemp
通讯作者：
J. Steppeler;J. Klemp
影响因子：
3.2
作者：
H. Yamazaki;T. Satomura
通讯作者：
H. Yamazaki;T. Satomura
影响因子：
3
作者：
Beth Good;A. Gadian;Sarah‐Jane Lock;A. Ross
通讯作者：
Beth Good;A. Gadian;Sarah‐Jane Lock;A. Ross
影响因子：
3.2
作者：
R. A. Madden;Jill Williams
通讯作者：
R. A. Madden;Jill Williams
DOI：
10.1016/j.jcp.2017.04.061
发表时间：
2017-02
期刊：
J. Comput. Phys.
影响因子：
--
作者：
James Shaw;H. Weller;J. Methven;T. Davies
通讯作者：
James Shaw;H. Weller;J. Methven;T. Davies