Open-Channel Flow Control by Vegetation and Artificial Roughness and Hydraulic Design of Multi-Function Channels

植被和人工粗糙度明渠流量控制及多功能渠道水力设计

基本信息

批准号：
06650558
负责人：
TSUJIMOTO Tetsuro
金额：
$ 1.28万
依托单位：
Kanazawa University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06650558/
关键词：
Flow with vegetation Artificial roughness Open-channel flow Hydraulic design Strip roughness Secondary flow Cellular motion Lateral diffusion 開水路乱流多機能水路数値解析

项目摘要

Recently, river improvement should be planned to refine various functional aspects of rivers such as flood control, more efficient water resources utilization, recreational or leisure usage of rivers, well-conserved ecological situation, aquatic habitat and so on. And to achieve such multi-functions, the flow and river morphology should be more skillfully managed or controlled based on hydraulics and mechanics of sediment transport.In this study, control of cellular motion by oblique arrangements of strip roughness and promotion of lateral diffusion by arrangement of vegetation zone have been focused. Cellular motion helps straight navigation of boat and canoe, or removed snow lumps by secondary flow motion, or it gathers floating garbage to remove them by side overflow. Furthermore, it even changes the primary velocity profile. Stream-type fish way is an example of the latter. While, the promoted lateral diffusion works to decrease the turbidity of the main channel by trapping it to the vegetation zone.In this study, various types of approaches have been employed : laboratory experiments, field measurements and numerical analysis as well as simplified hydraulic understanding of the phenomena. The mechanism of formation of cellular motion by obliquely arranged strip roughness on bed and/or side walls and promotion of lateral diffusion by vegetation zone have been understood at several levels. The experiment has provided empirical relations and they have been supported by numerical analysis. And, they must be useful for hydraulic design of multi-functional streams.

近期，应规划河流整治，细化河流的各个功能，如防洪、更有效地利用水资源、河流的娱乐或休闲利用、良好的生态状况、水生栖息地等。为了实现这种多功能，需要基于泥沙输运的水力学和力学，对水流和河流形态进行更巧妙的管理或控制。在本研究中，通过带状粗糙度的倾斜布置控制细胞运动，并通过布置促进横向扩散植被带受到重点关注。细胞运动有助于船只和独木舟的直线航行，或通过二次流动运动清除积雪，或收集漂浮垃圾并通过侧面溢流清除它们。此外，它甚至改变了主要速度分布。溪流式鱼道就是后者的一个例子。同时，促进的横向扩散通过将主河道的浊度捕获到植被区来降低主河道的浊度。在这项研究中，采用了各种类型的方法：实验室实验、现场测量和数值分析以及简化的水力理解的现象。通过在床和/或侧壁上倾斜布置的条状粗糙度形成细胞运动以及通过植被带促进横向扩散的机制已经在几个层面上得到了理解。实验提供了经验关系，并得到了数值分析的支持。而且，它们对于多功能流的水力设计必须有用。