Water Balance Calculation Based on Hydrodynamics in Reservoir Operation

Abstract

Reservoir operation plays an important role in reservoir management. In reservoir operation, water balance calculation is a very important step. At present, one of the main challenges is that reservoir inflow cannot be calculated accurately due to jacking of the reservoir, which is produced by a downstream reservoir after the original course of the river has changed. Another reason that reservoir capacity cannot be calculated accurately is due to the influence of dynamic storage capacity. In order to overcome these problems, this report shows that the land zone in front of the dam can be used to calculate reservoir capacity, since it can serve as the boundary for a hydrodynamic model, which can then be used to calculate reservoir inflow to improve accuracy. The Three Gorges Dam was selected as a case study. The results show that compared with the measured data, the RMSE (root mean square error) of the proposed model was 8.5%, whereas the RMSE of the traditional model was 25.9%. The contributions and novelty of this paper are: (a) the proposed model combines a hydrodynamic model with a water balance calculation model to make the calculation of inflow more accurate; (b) the land zone in front of the dam can be used to make the calculation of reservoir capacity more accurate; (c) the proposed method provides a new way to calculate water balance, which can be used for short-term reservoir operation. The application results indicate that this study can provide technical support for the fine operation of reservoirs.