Basic study of Design Method for the Main Channel of Meandering Compound Channels

曲流复合河道主河道设计方法基础研究

基本信息

批准号：
10450183
负责人：
FUKUOKA Shoji
金额：
$ 8.32万
依托单位：
Hiroshima University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10450183/
关键词：
Compound meandering channel Clnsteadiness of Flood flow Storage volume in a river Planform Numerical analysis Accuracy of discharge measurement 水理実験複断面河道蛇行洪水ハイドログラフ水位-流量関係相対水深河道設計

项目摘要

(1) Comparing stage hydrographs for meandering compound channel and meandering single channel it was observed that, compound meandering channel had early response giving high values during rising stage and delayed response giving high values during falling stage. Also for both compound meandering channel and meandering single channel, increase of sinuosity and unsteadiness brings faster occurrence of the maximum velocity and the large increase rate of the depth in the rising stage.(2) A quantitative estimation of the flood flow storage and attenuation of the peak discharge in channels was investigated. Laboratory experiments in a compound meandering channel were performed and observed flood data from Otagawa river were analyzed. Results of comparison of the experimental data and Otagawa river data indicated similar characteristics of flood flow storage.(3) A comparison between experimental results and a 2 -dimensional unsteady flow numerical model simulations is made for flood propagation in a compound meandering channel. The model is based on a finite volume discretization on a staggered gird with upwind scheme in flux is presented, it handles drying and wetting process for a flood plain, complex geometry and discontinuities, which are the main requirements for modeling compound channel flows. The existing knowledge on flood flow phenomenon in compound channels is advanced through comparative studies of unsteady flow experiments and numerical simulations. Comparison between measured date and model simulations show generally good agreement.(4) Since most of the rivers in Japan are compound meandering channels, which have complex flow field, we check the accuracy of discharge measurements of those compound channels. The accuracy of discharge measurements is investigated in a compound meandering channel by using a there dimensional numerical analysis. The discharge measurement is clarified from the Eulerian and the Lagrangian methods.

（1）比较曲折的复合通道和曲折的单个通道的阶段水文图，观察到，复合曲折的通道具有早期响应，在上升阶段的较高值和延迟响应中，在下降阶段延迟响应。同样，对于复合蜿蜒的通道和蜿蜒的单个通道，提高和不稳定的提高会使最大速度的发生速度更快，并且在上升阶段的深度速度大增加。进行了化合物蜿蜒通道中的实验室实验，并分析了大川河的洪水数据。实验数据和大川河数据的比较结果表明，洪水流量存储的特征相似。（3）实验结果与2维无稳定的流量流量模型模型之间的比较是在复合曲折通道中进行洪水繁殖的。该模型是基于在通量中带有上风方案的交错束束上的有限体积离散化，它处理了洪水，复杂的几何形状和不连续性的干燥和润湿过程，这是对复合通道流进行建模的主要要求。通过对不稳定的流动实验和数值模拟的比较研究，提出了有关复合通道中洪水流现象的现有知识。测量日期和模型仿真之间的比较通常显示出良好的一致性。（4）由于日本的大多数河流都是复合曲折的通道，它们具有复杂的流场，因此我们检查了这些化合物通道的排放测量值的准确性。通过使用其中的数值分析，在复合曲折通道中研究了放电测量的准确性。从Eulerian和Lagrangian方法阐明了排放测量。