Physical and numerical modelling for settling efficiency of desilting chamber

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.

KEYWORDS:

• Hydroelectric projects
• desilting chamber
• settling efficiency
• physical model
• CFD simulation

Acknowledgements

The authors sincerely thank Dr. R. S. Kankara, Director, CWPRS for constant encouragement, and guidance and kind permission for publishing this paper. The authors are also thankful to the project authorities for making available the necessary data for conducting these studies.

Disclosure statement

No potential conflict of interest was reported by the author(s).