NUMERICAL SIMULATION OF EROSION AND DEPOSITION IN THE BACKWATER REGION OF THE THREE GORGES PROJECT BEFORE/AFTER CONSTRUCTING THE JINGKOU AND XIAONANHAI HYDROPOWER PLANTS

摘要

In order to analyze the characteristics of erosion and deposition and the variations in flow conditions of the Chongqing port and waterway after the Jingkou hydropower plant on the Jialing River and the Xiaonanhai hydropower plant on the Yangtze River are built in the backwater region of the Three Gorges Project, a quasi-two dimensional numerical model for unsteady flow and sediment, ROEQ2D, developed by the authors, was applied to the comparative computation of erosion and deposition at the back water region of the Three Gorges Project before/after constructing the Jingkou and Xiaonanhai hydropower plants. The calculated results showed that deposition will greatly decrease, the water depth of the Chongqing port and waterway will increase, the flow conditions of the Chongqing port and waterway will be improved in the backwater region of the Three Gorges Project after the Jingkou and Xiaonanhai hydropower plants are built. The calculated quantities of erosion and deposition in the study domain are basically identical for the nine kinds of the joint operation plans decided by the different water discharges of the Jingkou and Xiaonanhai hydropower plants.