Meshless numerical models have attracted much attention due to the circumvention of troublesome mesh generation. Current meshless numerical groundwater (GW) models either focus on only pumping in fully saturated zone or merely simulate variably saturated GW flow without pumping. However, these two components are both essential for a GW model to represent practical real-world conditions. This gap is bridged in this study by developing a three-dimensional model, CCHE3D-GW-Meshless, using the meshless weak-strong form method. The new model code was verified with three representative cases, and good agreement was found with the analytical/numerical solutions in all cases. CCHE3D-GW-Meshless was then applied to a field case of a pumping well near a meandering river located at Shellmound, Mississippi, USA. The hydrological properties of the site were obtained through calibration which yielded a generally good match with observed data considering the incompletely known heterogeneity in aquifer properties, indicating the applicability of the model.

中文翻译：

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采用无网格弱强形式法的变饱和地下水流三维数值模型

无网格数值模型由于避免了麻烦的网格生成而引起了广泛关注。当前的无网格数值地下水 (GW) 模型要么仅关注完全饱和区域的抽水，要么仅模拟不抽水的可变饱和地下水流。然而，这两个组件对于 GW 模型代表实际的现实条件都是必不可少的。本研究通过使用无网格弱强形式方法开发三维模型 CCHE3D-GW-Meshless 来弥补这一差距。新的模型代码通过三个代表性案例进行了验证，并且在所有案例中都与解析/数值解有很好的一致性。随后，CCHE3D-GW-Meshless 被应用于美国密西西比州谢尔蒙德蜿蜒河流附近抽水井的现场案例。该地点的水文特性是通过校准获得的，考虑到含水层特性的不完全已知的异质性，与观测数据总体吻合良好，表明该模型的适用性。