黄河内蒙古段弯道河冰过程与卡冰机理研究

Processes and mechanics of ice jam formation in river bends of the Yellow River in Inner Mongolia

黄河内蒙古段弯道因其特殊的热力、动力和河道形态等因素的综合影响,在流凌期极易形成卡冰结坝的现象,造成冰凌灾害。在黄河内蒙古段2013年度冬季流凌至封河期间冰情观测的基础上,对三湖河口弯道处冰凌动力特性进行了数值模拟,揭示了弯道处在河道形态影响下的冰凌动力条件和封河特征,模拟了三湖河口弯道岸冰形成区域、形成过程和可能形成冰塞冰坝的位置。结果显示,受弯曲河道地形的影响,流凌在弯道内摆动轨迹复杂,流凌期首先在凸岸处会有大片岸冰生成,随之,在凸岸顶端下游束窄的断面处封河,此断面也成为可能最易形成冰坝的河道位置。

Ice jams could cause ice floods along the Yellow River in Inner Mongolia, which usually occurred in the river bends because of the specific thermodynamics, hydrodynamics, and river bathymetry during the freeze - up period in this area. The processes of ice jam formation were observed in the Yellow River in Inner Mongolia in the winter of 2013. Numerical simulation was used to get better understanding on the processes and mechanics of ice jam formation in a river bend near Sanhuhekou. The results showed that the ice formed firstly at the convex bank. The ice jam most likely formed at the downstream of the convex hank, where the width of the river bend is relatively narrow.