This paper presents a model for local scour at submerged weirs with downstream slopes that uses a coupled moving-mesh and masked-element approach. In the developed model, the fluid-sediment interface is tracked using a moving-mesh technique, and the effects of the structure on the hydrodynamics and bed morphology are resolved using a masked-element technique. Compared to traditional sediment scour models, based on the moving-mesh technique, the present model has the advantage of allowing for a simpler setup of the computational grids and a larger-amplitude deformation. Laboratory experiments on local scour at a submerged weir with a downstream slope were conducted, which provided bed profiles at different time instants. The results obtained by the present model are compared to the experimental data. The comparisons demonstrate the performance of the model in satisfactorily predicting local scour at a submerged weir with a downstream slope. The model was further modified and employed to carry out additional computations to investigate the influence of various parameters and sub-models.

本文提出了一种采用耦合移动网格和掩盖单元法的下游边坡淹水堰局部冲刷模型。在开发的模型中，使用移动网格技术跟踪流体-沉积物界面，并使用蒙面元素技术解决了结构对流体动力学和床层形态的影响。与传统的泥沙冲刷模型相比，基于移动网格技术，本模型的优点是可以简化计算网格的设置和较大幅度的变形。进行了对具有下游坡度的淹没堰的局部冲刷的实验室实验，该实验提供了不同时刻的河床剖面。通过本模型获得的结果与实验数据进行比较。比较结果表明，该模型可以令人满意地预测具有下游坡度的淹没堰处的局部冲刷。该模型被进一步修改并用于执行其他计算，以研究各种参数和子模型的影响。