中文摘要：

传统的MODFLOW采用结构化网格进行剖分,但是对刻画形状复杂的边界等实际问题存在局限性。最新的非结构化网格MODFLOW（MODFLOW-USG）能够提供更加灵活的网格剖分方法,并能够刻画形状不规则的边界、非均质地质体和不连续层等实际问题,提高模型仿真度与计算结果精度。利用MODFLOW-USG方法对黑河中游盆地地下水流动模型进行了研究,针对形状复杂、尺度不一的河流边界进行了精细化剖分,提高了河流及附近重点关注区模拟结果的准确性。

英文摘要：

The classic MODFLOW uses a structured grid which has problems in the discretization of model boundaries with complex irregular shapes. A new version of MODFLOW,called MODFLOW-USG（ for unstructured grid）,supports a wide flexible unstructured grid type that offers advantage for modeling irregular boundaries,homogeneous geological framework and discontinuous layer,etc,and improves the reliability and accuracy of the simulation results. This paper utilizes the MODFLOW-USG method to study the groundwater flow model of the middle reaches of the Heihe basin. The accuracy of the simulation results in the focused zone nearby the river has been improved by generating a finer unstructured grid for the irregular and various sized river boundary.