赣江入鄱阳湖北支封堵对尾闾河网水流特性影响试验研究

赣江下游尾闾河道为冲积性多级分汊型河道,主要分为西河、东河,西河分汊为西支和北支、东河分汊为中支和南支。由于水文情势的改变使得赣江水环境和航行条件恶化,拟封堵赣江入鄱阳湖北支以改善水流条件,而对河道的封堵会改变其它支流的水流条件。所以基于物理模型试验,通过分析北支封堵后赣江下游尾闾河网水位、流速、分流比等水流特性的变化,探讨入鄱阳湖北支封堵对尾闾河网水流特性的影响,为赣江尾闾河道整治提供技术依据。试验结果表明:封堵入鄱阳湖北支后,西河分流比减小,东河分流比增大,西支、中支、南支分流比增大,且水位都有所抬高,此外,由于分流比增大,西支、中支、南支部分断面流速增大。

Impacts of The North Branch Plugging on Flow Characteristic in Tail Channels of Ganjiang River Caused

The tail reaches of Ganjiang River are alluvial channels with multi-bifurcation,which mainly divided into East River and West River.The East River evolved into west branch and north branch and the West River evolved into middle branch and south branch.Due to the changes in hydrological regimes,water environment and navigation condition in Ganjiang River are deteriorating.The north branch regulation scheme was proposed to improve the flow condition,but flow condition in other branches will be changed as well.Based on the physical modelling experiments,this paper analyzed the change of flow characteristic in the tail reaches caused by plugging the north branch,including water level,velocity and water diversion ratio.The results show that when the north branch was plugged,the water diversion ratio of the West River is decreasing while the East River is increasing,and the water diversion ratio of west,middle and south branches is all increasing;water level in west,middle and south branches is rising;besides that,velocity in some of sections is increasing of west,middle and south branches.