Lateral velocity distribution in open channels with partially flexible submerged vegetation
Lateral velocity distribution in open channels with partially flexible submerged vegetation
复制标题
部分柔性水下植被明渠的横向速度分布
DOI：
10.1007/s10652-016-9485-9
复制
发表时间：
2016
影响因子：
2.2
通讯作者：
Zeng YH
中科院分区：
文献类型：
--
作者：
Han Lijuan;Zeng Yuhong;Chen Li;Huai Wenxin;Zeng YH
本研究实施三个分析模式，以探讨在一个矩形通道的横向，不均匀分布，灵活的沉水植被的深度平均流向速度的横向分布。在动量方程中引入了二次流、植被阻力和湍流剪切，以描述植被与水流的相互作用。模型结果和实验数据的比较表明，预测与混合层模型，它认为在混合区的二次流项，特别是高纵横比的通道得到改善。研究建立了植被阻力系数与雷诺数之间的关系。对无量纲涡动粘性系数和床面摩阻系数的敏感性分析表明，无量纲涡动粘性系数和床面摩阻系数对横向流速剖面的影响与第二个因素一样显著。合理的无量纲涡粘系数是准确预报流速的关键。
This study implemented three analytical models to investigate the lateral distribution of depth-averaged streamwise velocity in a rectangular channel with lateral, unevenly-distributed, flexible submerged vegetation. Secondary flow, vegetation drag, and turbulent shear were introduced into the momentum equations to represent the interaction between vegetation and flow. Comparison of model results and experimental data indicated that predictions were improved with a mixing layer model, which considers the secondary flow term in the mixing region, particularly for channels with a high aspect ratio. The research established a relationship between the vegetation drag coefficient and the Reynolds number. A sensitivity analysis of the dimensionless eddy viscosity coefficient and bed friction factor indicated that the coefficient had as significant an impact as the second factor on the lateral velocity profile. A reasonable dimensionless eddy viscosity coefficient is essential to predict velocity accurately.