堤防弯道决口逐渐溃决三维数值模拟  

Analysis of gradual dike bend breach through 3D numerical simulation

作　　者：王姣 吴泽亮 熊威 王萱子 胡强 WANG Jiao;WU Zeliang;XIONG Wei;WANG Xuanzi;HU Qiang(Jiangxi Academy of Water Science and Engineering,Nanchang 330029,China;School of Infrastructure Engineering,Nanchang University,Nanchang 330031,China)

机构地区：[1]江西省水利科学院,江西南昌330029 [2]南昌大学工程建设学院,江西南昌330031

出　　处：《水利水运工程学报》2024年第1期27-34,共8页Hydro-Science and Engineering

基　　金：江西省水利厅科技项目(202124ZDKT01,202123YBKT02,202224ZDKT07,202223YBKT15)。

摘　　要：针对堤防弯道溃决溃口全过程扩展规律及溃口水流水力学特性难以获取的问题,基于FLOW-3D软件,采用RNG k-ε湍流模型和泥沙模型,建立堤防弯道逐渐决口三维数值模型,模拟水槽内弯道的溃决过程,室内试验验证了所建立的逐渐溃决模型具有较好的精度与可靠性,并对某实际堤防弯道决口进行数值模拟计算。结果显示:位于诱导溃口的背水坡侧最先溃决,溃口呈V形向临水坡堤脚线发展,且每当溃口发展到地基后,溃口呈倒梯形横向展宽;在垂直溃决水流方向,溃口处的水深在溃口处呈两侧高、中部略低的波浪形,溃口处的流速中部快两侧慢,在平行溃决水流方向,水深沿溃决水流方向逐渐降低,水面线随时间逐渐平缓;流速变化规律为溃口下游50~100 m范围流速最大,最大流速的出现位置随着溃决时间沿水流方向推移。To address challenges in understanding the comprehensive dynamics of dike bend breaches and the hydraulic features during breach evolution,a 3D numerical model is constructed utilizing FLOW-3D software,RNG k-εturbulence model,and sediment model.The model simulates the gradual breach process in a flume,validated through laboratory tests for accuracy and reliability.Employing this model,the gradual breach of a dike bend is simulated,revealing that the initial breach occurs on the back slope,developing into a V-shape towards the water-facing slope’s toe line.As the breach reaches the foundation,it widens in an inverted trapezoid transverse direction.The analysis extends to the variations in water depth and flow velocity near the breach.Vertically,the highest water depth occurs on both sides of the breach,with a slightly lower and wavy middle;the flow velocity is faster in the middle and slower on the sides.Horizontally,the water depth gradually decreases along the breach flow direction,the water surface line flattens over time,and the maximum flow velocity is observed 50-100 m downstream of the dike.The location of the maximum flow velocity shifts with the breach’s progression over time.The established model enhances our understanding of dike bend breaches and contributes valuable insights into their hydraulic characteristics.

关 键 词：FLOW-3D 弯道堤防 溃决 溃口 水力学特性 

分 类 号：TV143[水利工程—水力学及河流动力学]