College of Water Resources & Civil Engineering, China Agricultural University, Beijing, 100083, China.
State Key Laboratory of Hydroscience & Engineering, Tsinghua University, Beijing, 100084, China; State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining, 810016, China.
J Environ Manage. 2022 Oct 15;320:115686. doi: 10.1016/j.jenvman.2022.115686. Epub 2022 Aug 1.
Sedimentation affects the normal function of reservoirs and is a decisive factor in the reservoir's service life. Flushing sediment during reservoir operation is an effective non-engineering measure to alleviate reservoir sedimentation; however, lowering water level to discharge more flow conflicts with hydropower generation. In this study, reservoir management software is developed to simultaneously optimise sediment discharge and hydropower generation with the reservoir discharge as the decision variables. The sediment transport rate is calculated by an integral of the vertical distribution of suspended load concentration and flow velocity instead of empirical formulas. The model is solved by the most widely used multi-objective optimisation algorithm NSGA-II, resulting in the optimal schedule corresponding to the maximal sediment discharge and hydropower generation, which can be displayed graphically in the software. The software was developed in MATLAB with a Graphical User Interface (GUI) and applied to a large reservoir and can be generalised to other reservoirs. The results show that within the recommended discharge variation of 5%, the sediment release can be increased by 2.07 × 10 t as a reduction of per 10 kW h in annual power generation. Compared with the original scheme, sediment release can be increased most by 3.31% at the cost of 0.03% loss of power generation. Moreover, the dual objective in the flood season was optimised by 7.30% and 3.92%, respectively.
淤积会影响水库的正常功能,是决定水库使用寿命的关键因素。在水库运行过程中冲沙是缓解水库淤积的有效非工程措施,但降低水位以排放更多流量会与水力发电产生冲突。本研究开发了水库管理软件,以水库排放量为决策变量,同时优化排沙和水力发电。泥沙输移率通过悬浮负荷浓度和流速的垂向分布积分计算,而不是经验公式。模型采用最广泛使用的多目标优化算法 NSGA-II 求解,得到最大排沙和最大水力发电对应的最优方案,并在软件中以图形方式显示。该软件采用 MATLAB 编写,具有图形用户界面(GUI),并应用于大型水库,可推广应用于其他水库。结果表明,在推荐的 5%排放量变化范围内,每年减少 10kW·h 电量可增加 2.07×10^6t 的泥沙释放量。与原始方案相比,排沙量最多可增加 3.31%,而发电量损失仅为 0.03%。此外,洪水季节的双目标分别优化了 7.30%和 3.92%。