Study on three-dimensional mechanisms of flow and sediment transport in open channels with permeable and impermeable spur-dikes

本文对丁坝周围水流结构和泥沙输移机理进行了研究，旨在加深对丁坝设施环境应用的认识。通过对试验结果的图像分析，阐明了水流和泥沙运动的三维结构。结果表明，透水丁坝尾流和淹没丁坝溢流对泥沙悬浮起着重要作用。在此基础上，建立了一个能较好地模拟透水堤周围含沙量分布的悬沙输移数学模型。

The mechanisms of flow structures and sediment transport around spur-dikes were studied in order to extend our knowledge of environmental applications of spur-dike installations. By applying image-analysis methods to experimental results, three-dimensional structures of flow and sediment transport were clarified. The results showed that the wake flow behind permeable dikes and the over-flow on submerged spur-dikes play important roles on sediment suspension. A numerical model of suspended sediment transport that can reproduce sediment concentration profile around permeable dikes was then developed based on the experimental results.