Experimental and numerical simulations of the hydraulic flushing of reservoir sedimentation for planning and design of a hydropower project

摘要

Hydropower projects located on rivers transporting heavy sediment loads requiredesign and operation criteria based on sediment management as a means of sustainingthe project life. Sediment management is achieved by designing projects as a runof‐the‐river scheme, with provision for drawdown flushing, noting hydraulic modelsimulations are essential for optimizing the design of these projects. Sediment depositionlevels are generally predicted with long‐term simulations using 1‐D numericalmodels, as well as experiments with scaled physical models that simulate drawdownflushing. The present study presents experiments with scaled model and 3‐D numericalmodel simulations conducted for hydraulic flushing of a reservoir. Experimentswere conducted for various durations and discharges to finalize the intake alignmentand optimize the flushing. The results of the 3‐D numerical model simulations are inagreement with the results of the experimental study (4%–6% variation). The resultsalso indicate a combination of a 1‐D numerical model for sedimentation and a 3‐Dnumerical model for flushing can be effectively used to simulate the sedimentationand flushing of reservoirs during the planning and design stages.