Author(s): Mehmet Salih Turker; Serhat Kucukali

Linked Author(s): Serhat Kucukali

Keywords: pool-weir fish pass; flexible hydraulics elements; flow field; low-velocity zone; turbulence

Abstract: The objective of this study is to develop alternative pathways for migration and enhance the effectiveness of the existing pool-weir fish pass, which is the most widely used fish pass type in operation in Turkey and around the world. To achieve this goal, the hydrodynamic characteristics were monitored and assessed simultaneously at the Dagdelen Small Hydropower plant in the Ceyhan River Basin, Turkey by using real-time operation conditions. The performance of flexible cylindrical hydraulic elements, which offer a cost-efficient method for creating resting areas and reducing macro-turbulence, was tested on a prototype scale. To obtain real-time data, 3D velocity measurements were conducted in the fishway pool using an Acoustic Doppler Velocimeter. The measurements were taken with and without bristles. The spatial distributions of velocity vectors and turbulent kinetic energy were analyzed by taking in-situ measurements and numerical simulations for two distinct hydraulic conditions. It was observed that the existing structure of the fishway produced a turbulent jet, resulting in high velocities and turbulent fluctuations in the pool. The monitoring data and numerical simulations showed that low velocity and turbulent kinetic energy regions were created behind the brush block, and the porous media approach has satisfactory results for flexible hydraulic elements. The proposed numerical modeling approach is expected to make contributions to the refurbishment studies of existing pool-weir fishways.

DOI: https://doi.org/10.3929/ethz-b-000675921

Year: 2024