Physical and numerical modelling for settling efficiency of desilting chamber

Abstract

ABSTRACT In this work, a desilting chamber of the Kholongchhu Hydroelectric Project, Bhutan, was used to test the settling efficiency using physical model and Flow-3D, a three-dimensional computational fluid dynamics (CFD) software. As sediment particles greater than a particular size can cause erosion and damage to underwater machinery, the estimation of settling efficiency is essential during the planning, designing and implementation phases of hydropower projects. These studies were carried out using 12 distinct particle sizes (0.25 mm, 0.24 mm, 0.23 mm, 0.22 mm, 0.21 mm, 0.2 mm, 0.19 mm, 0.18 mm, 0.17 mm, 0.16 mm, 0.15 mm and 0.1 mm). The settling efficiency for the particle size 0.2 mm obtained by physical model and CFD simulations were 92.2% and 93.6%, respectively.