Author(s): Ana Hosseinpour; Leslie Dolcine; Musandji Fuamba
Linked Author(s): Musandji Fuamba
Keywords: Water balance equation; Wind; Evaporation; Natural flow; Hydrodynamic model
Abstract: Accurate estimation of natural flow is one of the main concerns in water resource management and planning. Water Balance Equation (WBE) is commonly used to estimate flow; however several uncertainties affect the accuracy of this method. The authors sought to define the importance of these uncertainties on natural inflow. In this paper, they report on a case study that employed different methods to determine daily evaporation from the surface of different sized reservoirs and apply a two-dimensional hydrodynamic model to evaluate the impact of water level uncertainties caused by wind on natural inflow calculations. The wind-drag coefficient is calibrated with hydrometric and meteorological data, and the effect of wind stress on the hydroelectric reservoir is evaluated for varying operating levels. Results show that the importance of evaporation depends on the season and the reservoir surface, and that the effect of wind on natural flow estimation depends on its velocity, direction and on the operating water level. Although these effects are negligible in some cases, in others they considerably alter the results of WBE.
Year: 2013