水科学进展2016，Vol.27Issue(6)：849-857,9.DOI:10.14042/j.cnki.32.1309.2016.06.007
基于高速摄像技术的推移质运动特征试验
Experimental study of bed load movement characteristics based on high speed video measurement
摘要
Abstract
Bed load transport is closely connected with the turbulent structures of open-channel flow. Studies on the interaction between the movement of sediment particles and flow turbulence are of essential significance to both fluid mechanics and river dynamics. Flume experiments with low equilibrium transport of uniform sediment at different flow conditions were conducted to study the mechanism of interaction between turbulence and sediment movement. The mo-tion of particles on the whole bed were identified by examining the gray difference between the two successive images. Analysis of the measurements yields the following findings:①Influenced by the transverse distribution of flow intensi-ty, the probability for sediment movement was symmetric transversely, reaching its maximum at the center and decrea-sing gradually toward the side wall;② Under the influence of turbulent coherent structure, particles accumulated at the region of low-speed streaky structure and were scoured at the region of high-speed streaky structure. The probabili-ty for sediment movement exhibited high-and low-speed streaky regions alternatly in the z direction;③The increase of friction Reynolds number led to an increase in the interval of the nearby high sediment transport rate regions, ran-ging from 0. 13 to 0. 24 times as the width of flume;④ Under different flow conditions, the values of D/H remained 2, which corresponded to the conceptual model of streamwise vortex, indicating that the structure of streamwise vortex was an important factor to the formation of the alternating concave and convex sediment structures.关键词
推移质/运动特征/图像处理/条带结构/流向涡Key words
bed load/movement characteristic/image processing/streaky structure/streamwise vortex分类
建筑与水利引用本文复制引用
王浩,袁强,孟震,龚家国..基于高速摄像技术的推移质运动特征试验[J].水科学进展,2016,27(6):849-857,9.基金项目
国家自然科学基金资助项目 （）
