三峡枢纽典型碍航河段复杂流态分析

石牌弯道航段是长江三峡和葛洲坝两坝间典型的急弯航段，受复杂河床地形和急弯影响，流态复杂多变，特别是汛期，随着流速和流量增大，漩水、斜流、剪刀水等不良碍航流态频发，严重影响船舶通航安全。为降低汛期该航段通航风险，提升通航率，本文采用数值模拟与实测数据结合的方式，首先基于MIKE21软件，建立了该弯道二维数值模型；然后结合实测数据完成了模型可靠度验证；最后利用经过验证的数值模型，分析不同流量下石牌弯道航段流态特点，理清不同流量下，漩水、斜流、剪刀水等碍航流态发生概率、位置和规模的变化规律，可为汛期该航段通航管控和航行安全提供重要参考。

Complex flow pattern in typical navigation obstructed region of Three Gorges Project

The Shipai bend section is a typical sharp bend section between the Three Gorges and Gezhouba dams of the Yangtze River.Affected by the complex riverbed topography and sharp bends,the flow pattern is complex and changeable.Especially in the flood season,with the increase of flow velocity and flow rate,the bad flow patterns such as swirling water,oblique flow and scissors water frequently occur,which seriously affects the safety of ship navigation.In order to reduce the navigation risk of this section in flood season and improve the navigation rate,this paper adopts the combination of numerical simulation and measured data.Firstly,based on MIKE21 software,a two-dimensional numerical model of the curve is established.Then combined with the measured data,the reliability of the model is verified.Finally,the verified numerical model is used to analyze the flow characteristics of Shipai curve section under different flow rates.The variation rules of the occurrence probability,location and scale of navigation-obstructing flow patterns such as swirling water,oblique flow and scissors water under different flow rates are clarified,which provides an important reference for the navigation control and navigation safety of this section during flood season.