黄河吴堡-潼关河段洪水传播时间的沿程分布

Distribution of Flood Travel Time Along the Wubao-Tongguan Reach of Yellow River

黄河中游洪水传播时间的研究多侧重于统计洪水资料来获得龙门站洪水传播至潼关的时间,而忽略了洪水传播时间的沿程分布。以吴堡-潼关河段2010年地形资料为基础,采用一维水动力学模型分析了河段内洪水至潼关的时间及其与洪水量级的关系。分析发现,由于龙门-潼关河段的游荡型河道特点,吴堡-潼关区间的洪水传播时间沿程分布存在一个下包络线。若以潼关站洪水30h预见期作为实践需求,无定河以下的各主要支流都需要一定的洪水预见期。分析得到吴堡-龙门段及龙门-潼关段洪水传播时间与距潼关距离及洪水流量的关系式,可为潼关站洪水预报提供参考。

Previous research has been focused on the flood travel time in the LongmenTongguan reach of the Middle Yellow River based on statistical analysis of the flood data, and less attention has been paid on the distribution of flood travel time along the river course. This paper presents a onedimensional hydrodynamic model to analyze the relationship between the flood travel time and the flood discharge levels based on the topographic data between Wubao and Tongguan in 2010. Due to that the river reach between Longmen and Tongguan is a braided river, the results show that a lower envelope exists in the distribution of the flood travel time along the WubaoTongguan Reach. In order to achieve a forecast lead time of 30 hours at the Tongguan Sta tion, the flood in the tributaries downstream the Wuding River should be forecasted ahead. Additionally, the relationships among the flood travel time, the distance to the Tongguan station, and the flood discharge are investigated for two reaches： Wubao Longmen and LongmenTongguan. The proposed regression equations are useful in the practice of flood forecast.