Numerical simulation of sediment deposition and trapping efficiency estimation in settling basins, considering secondary flows

In this paper, sediment deposition and trapping efficiency in shallow rectangular reservoirs were numerically estimated considering secondary flows. In order to do this, three dimensional (3D) steady, incompressible, Reynolds-averaged Navier-Stokes (RANS) equations with the standard k - epsilon turbulence model were used as the governing equations. The drift-flux model also was used to model the solid phase. In the next step, the developed model was validated using the available data. Then it was used to simulate the sediment deposition and trapping efficiency in shallow rectangular reservoirs, considering secondary flows. The results show the sediment is trapped in the inlet corner of the reservoir, and two pairs of large vortices on the sides and two pairs of small vortices at the inlet corner of the reservoir are observed. Finally, the effects of the input angle of the reservoir to the trapping efficiency are evaluated and the results are discussed. (C) 2020 International Research and Training Centre on Erosion and Sedimentation/the World Association for Sedimentation and Erosion Research. Published by Elsevier B.V. All rights reserved.