溃堤洪水分析的一、二维水动力耦合模型及应用

建立一、二维水动力耦合数学模型以模拟溃堤洪水的演进过程,其中一维模型采用Preissmann格式离散,二维模型利用基于非结构网格的Roe格式离散。将道路、灌渠等特殊边界概化为宽顶堰并作线性处理,利用非结构网格与特殊边界的耦联,建立具有真实地形的耦合模型,并采用干湿水深理论对模型进行优化。将模型应用于黄河青铜峡河西灌区溃堤洪水的模拟,较为真实地再现了洪水在计算区域内的演进过程与淹没范围,体现了道路、灌渠等特殊边界的阻水效果与桥涵的过水效果。

A coupled one- and two-dimensional hydrodynamic model for analysis of levee-breach flood and its application

A coupled one- and two-dimensional hydrodynamic model was developed to simulate the flood wave propagation through the breaches. The Preissmann scheme was used for the one-dimensional model and the Roe scheme on unstructured meshes was used for the two-dimensional model. The special boundaries, such as roads and irrigation ditches, were generalized as broad crested weirs and were linearized. A coupled model with real terrain was established through coupling the unstructured mesh and special boundaries, and the dry and wet depth theory was used to optimize this model. The model was applied to simulation of a levee-breach flood that occurred in the West Irrigation Area of the Qingtongxia Gorge of the Yellow River. The results show that the model can truly simulate the flood wave propagation and flood inundation area in the calculation area, and can simulate the water-blocking effect of roads and irrigation ditches and water-passing effect of bridges and culverts.