一维模型模拟局部溃坝洪水方法的合理性验证

用一维非恒定流数学模型进行局部溃坝水流模拟计算时，由于坝址断面的水流存在间断，溃口处的流量不能通过模型本身算出，须引用水力学中的堰流流量公式。为验证宽顶堰流流量计算公式用于局部溃口流量过程计算的合理性，本文采用平面二维数学模型对其进行了验证计算。一维数学模型与二维模型计算得到的溃坝流量过程符合良好，流量峰值差值在 5%以内，与局部溃坝坝址最大流量计算经验公式结果也很接近。表明一维数学模型模拟局部溃坝时，溃口断面处的流量采用一般宽顶堰流量计算公式是可行的。

Verification of 1-D Model to Simulate Partial Dam Break Flow

Because of discontinuity of flow at the cross section of dam site for partial dam break flow, discharge therein could not be computed directly from the 1-D unsteady flow equations. Weir formula of wide crest flow is usually adopted in 1-Dmodel to simulate such flow. As weir flow formula is originally obtained under steady flow condition, verification is needed before applying to such strong unsteady flow. To do so, in this paper, 2-D model was introduced because, under certain conditions, out flow discharge at the dam site of partial dam break can be computed automatically. Computation shows that discharge process of 1-D and 2-D model agree quite well, and differences of peak discharges are within the range of ±5%, computed peak discharge is also very close to the empirical formula result at dam site for partial dam break flow. Coupling of weir formula with 1-D unsteady flow equation is applicable for the simulation of the partial dam break flow.