Open access
Date
2020-01Type
- Journal Article
Abstract
Horizontal bar racks used as fish protection measures at hydropower plants have rapidly gained importance in recent years. Despite the large number of installed racks in Europe, systematic investigations of the hydraulic losses and velocity fields were missing. To fill these research gaps, the hydraulic performance of horizontal bar racks was systematically investigated in a laboratory flume for a large number of rack parameters and different hydropower plant layouts. The results of the head loss assessment are published in a paper entitled Head Losses of Horizontal Bar Racks as Fish Guidance Structures, whereas the present paper focuses on the velocity fields. The measurements show that the bar shape, the horizontal approach flow angle, and the clear bar spacing have only a minor effect on the velocity fields. In contrast, bottom and top overlays might enhance the fish guidance efficiency for bottom and surface oriented fish, while the asymmetric downstream velocity field can reduce turbine efficiencies. The hydropower plant layout strongly affects the approach flow field to horizontal bar racks. For block-type hydropower plants, the installation of a dividing pier or partial opening of the spillways improves the flow field for better fish guidance. Show more
Permanent link
https://doi.org/10.3929/ethz-b-000392396Publication status
publishedExternal links
Journal / series
WaterVolume
Pages / Article No.
Publisher
MDPISubject
Downstream fish migration; Fish control structures; Fish guidance structure; Fish passages; Fish protection; Flow fields; Horizontal bar rack; Laboratory studies; Velocity fieldsOrganisational unit
03820 - Boes, Robert / Boes, Robert
Funding
727830 - Fishfriendly Innovative Technologies for Hydropower (SBFI)
Related publications and datasets
Is cited by: https://doi.org/10.3929/ethz-b-000455545
More
Show all metadata