河道溃堤水波的物理模型实验研究  

An experimental study of propagation of dike-break waves

作　　者：陆灵威 林斌良[1] 孙健[1] 刘璐[1] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [2]广州地铁设计研究院有限公司,广州510010

出　　处：《水力发电学报》2016年第11期25-34,共10页Journal of Hydroelectric Engineering

基　　金：水沙科学与水利水电工程国家重点实验室科研课题项目(2015-KY-2);全球创新计划(GII)项目(20153000379)

摘　　要：河道堤坝溃决是我国易发灾害之一。溃堤将引发河道外洪水灾害和河道内水位流量的波动。现有溃堤研究多集中于应用数学模型模拟,现场观测和物理实验等直接观察获得的成果非常有限。本文通过在大型室内水槽中进行的物理模型实验,模拟了溃堤后洪水在溃口外洪泛区内的演进和落水波在河道内的传播过程。通过压力传感器阵列和声学多普勒流速仪对溃堤引发的水位、流速等变量进行了测量,并对溃堤波演变过程进行了研究。实验结果表明:(1)河道内的流速对于溃口下游洪水波的传播速度影响不大,但对溃口外水位的分布有一定的影响;(2)溃堤引发的河道内落水波在溃口上下游的影响不对称,落水波向上游传播较慢但幅度较大,而向下游传播较快但幅度较小;(3)溃堤发生后溃口流量随时间发生变化,水流稳定后溃口流量主要和上下游流量差有关,即溃口水流处于稳定分流状态。实验成果可为溃堤洪水动力学分析提供可靠的数据,为数学模型提供较为完整的验证资料,进而对河道溃堤洪水的预防和灾害控制提供科学的支撑作用。Dike breaking is a type of frequent disasters in China. It often causes flood flows outside the dike and water level fluctuations in the river channel. So far, numerical models are widely used to simulate dike-break flooding, while direct observations from field surveys and physical models are rather limited. In this study, physical experiments have been conducted in a large laboratory flume to simulate propagations of dike-break induced flood waves in flooded area and flow fluctuations in river channel. Variations in water level and discharge were measured and investigated by using a pressure sensor array and two acoustic doppler velocimetries. The results show that： a） flow in the river channel has little influence on the propagation of the dike-break flood waves, while it has remarkable effect on water level distribution; b） in the channel the dike-break induced water dropping caused asymmetrical waves, which propagated slowly upstream with large amplitudes and fast downstream with small amplitudes; c） at the initial stage of dike-break flooding, the rate of flow through the breach varied over time, it was gradually approaching a steady state, and the steady flow rate was related to the difference in discharges at the upstream and downstream sections. The experimental results would provide useful and reliable information for analysis of dike-break flow dynamics and verification of numerical models and for the benefit of flood and disaster control in river management.

关 键 词：水动力学 溃堤 物理实验 洪水 河道 洪泛区 

分 类 号：TV131.61[水利工程—水力学及河流动力学]