To predict the phreatic surface and conduct flood routing of rockfill dams, the flow hydraulics and rating curve need to be simulated. In this research, one-dimensional flow hydraulics through a trapezoidal rockfill dam was modelled via the standard step method. Regarding the non-Darcy flow, the relationship between the hydraulic gradient and the bulk velocity in power form was adopted. Using the exit height as the boundary condition significantly improves the prediction of the phreatic surface. For this purpose, a modified Pavlovsky equation was introduced. The advantage of the proposed method is that, unlike in previous studies, the downstream water level is used to estimate the exit height instead of the upstream water level, which makes the model more grounded on steady gradually varying flow. The proposed model has the capability of predicting the reservoir head–outflow relationship and routed hydrographs with high accuracy comparable with that of two-dimensional models.

中文翻译：

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考虑出口高度的堆石坝一维洪水演进模型

为了预测潜水面并进行堆石坝的洪水调度，需要模拟水流和额定曲线。在这项研究中，通过标准阶梯法对梯形堆石坝的一维流动水力进行了建模。对于非达西流，采用了水力梯度与动力形式的体速度之间的关系。将出口高度用作边界条件可显着改善潜水面的预测。为此目的，引入了修改的Pavlovsky方程。所提出的方法的优点是，与以前的研究不同，下游水位用于估计出口高度，而不是上游水位，这使得模型更基于稳定的逐渐变化的流量。