Causes of distribution characteristic of flushing time of Xiangxi bay in autumn
ZHANG Hongqing1,2, DAI Huichao3, BAO Zhongjin1, WANG Bin1, WANG Ziming1
1. Zhejiang Institute of Hydraulics & Estuary, Hangzhou, Zhejiang 310020, China; 2. College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, Zhejiang 310058, China; 3. College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, Jiangsu 210098, China
Abstract：For the problem of algal bloom of tributaries of the Three Gorges Reservoir in autumn, 3D hydrodynamic model, based on the background of the Xiangxi River was set up to explore the flushing time distribution and its causes during Sep.1 to Nov.30. Results show that in the storage period of the Three Gorges Reservoir, the areas of longer flushing time mainly focus on the middle of tributary embayment of the Xiangxi River, and the maximum of flushing time at every layer of tributary embayment increases as the water level rises at the end of flood season; in the following middle and lower area of tributary embayment, flushing time of the surface layer is the longest owing to trunk stream decanted into the tributary embayment from the middle and bottom layers, and the difference of flushing time between the surface and middle and bottom layers nearby tributary embayment estuary increases with the duration of trunk stream intrusion increasing. In the upstream and middle and upper areas, the flow direction is from the bottom of the tributary embayment to trunk stream within most of the time of this period, so flushing time at the bottom of this area is shorter than that at the surface and middle layers. The results can provide a reference for preventing and controlling the fall blooms problems of tributaries embayment of the Three Gorges Reservoir.
张鸿清,, 戴会超, 包中进, 王斌, 王自明. 秋季香溪河库湾水体冲淡时间分布特征的成因[J]. 排灌机械工程学报, 2016, 34(6): 511-517.
ZHANG Hongqing,, DAI Huichao, BAO Zhongjin, WANG Bin, WANG Ziming. Causes of distribution characteristic of flushing time of Xiangxi bay in autumn. Journal of Drainage and Irrigation Machinery Engin, 2016, 34(6): 511-517.
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