摘要
Submerged vanes are low-height flow-training structures emerging from the riverbed with a suitable angle of attack to the incoming flow. These structures redirect the stream flow and modify erosion and depositional rates in the bottom and in the banks of a river as a result of the secondary currents generated by their installation. For this reason they have many applica- tions in river hydraulics for controlling river bed morphology. An experimental investigation is carried out to compare the effi- ciency of sheet-piling vanes versus thin plane ones in controlling sediment redistribution in the channel bed. In particular, exper- imental tests were carried out within a straight water channel, in conditions of bed load motion. The morphology of the river bed both in the area close to the structure and in the far field was examined at different angles of attack of the vane to the incoming flow and at different values of the submergence parameter, which is the ratio between the height of the water above the structure and the water level. The experimental results show that both the shape of the vanes as well as the angle of attack affect their per- formance in terms of the effects on the bed morphology, especially for greater submergence parameters. Specifically, plane and sheet-piling vanes produce comparable remodelings of the channel bed in the downstream region, but when the attack angle is increased, the thin plane vane causes deeper scour holes close to the structure. This last effect is probably due to the increased erosive capacity of the horseshoe vortex associated with the plane vane, while the uneven surface of the sheet-piling vane miti- gates the erosive strength of that vortex.
题目：水下板桩叶片对移动河床的影响研究 目的：比较板桩叶片和简单的平板叶片在控制河床沉积物再分配时的效率。 方法：1.在不受当地侵蚀现象影响的接近障碍物和下游区域的直线水道中研究河床的形态；2.使用不同的实验装置测试简单几何形状的平板叶片和复杂形状的603 K 叶片的性能；3.在不同的叶片迎角和浸没参数下，测试与其面积接近的结构和在远场中的河床形态。 结论：1.叶片的形状和迎角影响其对河床形态所产生的作用，尤其是对于较大的淹没参数而言；2.平板叶片和板桩叶片对下游河床的重塑作用相似；3.随着迎角的增加，平板叶片将造成更深的冲刷孔。这可能归因于与平板叶片相关的马蹄形涡流增加的侵蚀能力，而板桩叶片的不均匀表面可减轻该涡旋的侵蚀强度。
