Effect of Outlet Configurations on the Removal of Fine Noncohesive Sediment by Vortex Settling Basin at Small River Abstraction Works

Abstract

The effect of varying vortex settling basin (VSB) outlet configurations on the removal of sediment particles >75 μm was computationally investigated using ANSYS Fluent’s Euler-Lagrange approach, which incorporated supervised optimization and was validated by physical modeling. A rectangular centroidal outlet was established with a low outlet weir and a shaft with the following dimensions: length equal to it 1.28* Inlet diameter, breadth equal to inlet diameter, and height equal to inlet diameter located 180° opposite the inlet. The shaft was designed for partially full conditions. A low weir height with less than the submergence depth is recommended at small river abstraction works (<100 L·s−1).