On resuspension and control of reservoir sediments by surface waves and point absorbers

Abstract

Consideration is given to a novel approach for resuspension and control of sediment in reservoirs which nowadays and after more than six decades of research remains as the most serious technical problem faced by dam industry. Here, it is proposed the generation of mild surface waves in the reservoir which -because the physical nature of the waves, will spread throughout the reservoir. Then, by using a farm of point absorbers -or technology akin as used in ocean energy conversion, the energy transported by the waves can be transformed into a continuous injection of water flow in the riverbeds balancing the gravitational settling and then in the resuspension and control of sediment settlement. Utilizing a simplified physical model an estimation of the area of riverbed covered in comparison with the area of point absorber needed was derived as function of several parameters. Methods for wave generation were briefly discussed and Computational Fluid Dynamics (CFDs) simulations performed being in good agreement with the theoretical estimations. The proposed concept is presented as a promising alternative technique which can contribute to mitigate the serious global problem of land loss in the river deltas as well as increasing the storable capability and life of large dams.