三峡水库调节作用对长江近河口段水文水动力特性影响

为了评估三峡水库蓄水对长江感潮河段水文水动力特性的影响,建立了具有预测功能的水动力模型。考虑径流与潮流之间的相互作用,模型在只有上边界流量过程的条件下可以给出下边界的潮位过程。在此基础上应用一维河网非恒定流数学模型,对三峡水库蓄水前后长江近河口段大通—徐六泾的水流运动进行了10年的数值模拟。统计分析结果表明,水库调蓄作用对感潮河段各站的潮位累积频率及水文水动力因素的年内过程变化影响甚大。

Effects of the Three Gorges Reservoir on hydrodynamics in tidal reach of the Yangtze River

A predictable hydrodynamic model was established to evaluate the impact of the Three Gorges Reservoir on hydrodynamics along the tidal reach of the Yangtze River. With merely upstream discharge boundary condition, the model was able to provide the downstream boundary condition considering interaction between the river runoff and the ocean tide. Quantitative analysis was achieved with 10-year continuous simulations of a one-dimensional (1D) unsteady numerical model of channel network in tidal reach of the Yangtze River from Datong to Xuliujing before and after the impoundment of the Three Gorges Reservoir. Statistical result indicates that runoff regulation of the reservoir plays an important role in both cumulative frequencies of tidal level and seasonal hydrodynamic processes.