向家坝下长江干流长河段河道横剖面分形特征  

Fractal research of long river channel's transverse section downstream Xiangjiaba Dam of Changjiang River

作　　者：倪志辉[1,2,3] 周舟[1] 吴立春[4] 钟亮[2] 赵健[3] 

机构地区：[1]重庆交通大学水利水运工程教育部重点实验室,重庆400074 [2]重庆交通大学国家内河航道整治工程技术研究中心,重庆400074 [3]重庆交通大学西南水运工程科学研究所,重庆400016 [4]重庆第二师范学院,重庆400067

出　　处：《水利水电科技进展》2017年第1期60-67,共8页Advances in Science and Technology of Water Resources

基　　金：国家重点基础研究发展计划(2016YFC0402104);重庆市基础与前沿研究计划(cstc2016jcyjA0380);内河航道整治技术交通行业重点实验室开放基金(NHHD-201514)

摘　　要：以长江干流向家坝—朱沱河段内局部碍航滩段为研究对象,建立二维非恒定-分形数学模型,统计满足最低维护水深的航道宽度,计算河道横剖面分维数,显示其呈1阶分维特性。河流宽度分维数和水深以及与所在河段、所在断面的形状有很大关系,一般浅滩呈现宽度分维数随水深增大而增大的趋势,横剖面分维数随流速增大整体上呈逐渐减小的趋势。对比同一河段内各滩分维数的大小,在上游流量相同时,河道横断面地形越平顺横剖面分维数越小。Using a navigation-obstructing section downstream the Xiangjiaba Dam of Changjiang River as a research object, a two-dimensional unsteady fractal mathematical model that can meet the requirement for maintaining a minimum water depth was established for statistical analysis of the channel width, and the fractal dimension of the river channel＇ s transverse section was calculated, demonstrating one-order fractal dimension characteristics. The results show that the fractal dimension of the channel width has a close relationship with the water depth, the topography of river reach, and the shape of transverse section, demonstrating a general increasing trend of the fractal dimension of the channel width with the increasing water depth for a shoal and a general decreasing trend of the fractal dimension of the transverse section with the increasing flow velocity. Comparison of the fractal dimension of different shoals in the same river reach shows that the fractal dimension is relatively small for a transverse section with smooth topography under the same flow rate from upstream.

关 键 词：分形维数 横剖面分形 数值模拟 非恒定流 通航水力要素 向家坝 长江 

分 类 号：TV147[水利工程—水力学及河流动力学]