Claudia Beck


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Beck

First Name

Claudia

ORCID

0000-0001-9021-1378

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2018 - 201982020 - 202218
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Publications 1 - 10 of 26
  • Fish Swimming Behavior and Bypass Acceptance at Curved-Bar Rack Bypass Systems
    Item type: Conference Paper
    Beck, Claudia; Albayrak, Ismail; Meister, Julian; et al. (2022)
    Proceedings 39th IAHR World Congress
    The present study deals with the hydraulic and fish-biological performance of an innovative curved-bar rack bypass system (CBR-BS). CBR is a mechanical behavioral fish guidance structure typically combined with a BS, that was developed at VAW of ETH Zurich for safe downstream fish passage at hydropower plants. A hydraulically optimized CBR with a full-depth BS was tested with six European fish species, namely, spirlin, nase, barbel, Atlantic salmon parr, brown trout and European eel in an ethohydraulic laboratory flume. The approach flow velocities were 0.50 and 0.70 m/s and the velocity ratios (VR) of mean bypass inlet velocity to mean approach flow velocity were 1.2 and 1.4 for each flow velocity, resulting in four different hydraulic conditions. The flow field around the CBR-BS was numerically simulated for each hydraulic condition with a CFD model. The simulation results show that the velocity gradients between the curved bars and up to ~40 mm upstream from the rack are high. The live-fish tests showed that such high velocity gradients triggered an avoidance reaction of spirlin, nase, barbel, salmon parr and partly brown trout, but not of eel. Fish guidance and protection efficiencies of the CBR-BS were higher than 75% for spirlin, barbel, nase and Atlantic salmon parr, whereas they were lower than 75% and 50% for brown trout and European eel, respectively. Increasing VR from 1.2 to 1.4 significantly decreased the number of bypass passages underlining the importance of bypass design. Recommendations for an optimized and economic CBR-BS design are given.
  • Fishfriendly Innovative Technologies for hydropower (FIThydro)
    Item type: Other Conference Item
    Meister, Julian; Beck, Claudia; Fuchs, Helge; et al. (2018)
  • Fish-friendly Innovative Technologies for Hydropower
    Item type: Report
    Albayrak, Ismail; Boes, Robert; Beck, Claudia; et al. (2020)
  • Fish protection and fish guidance at water intakes using innovative curved-bar rack bypass systems
    Item type: Doctoral Thesis
    Beck, Claudia (2020)
    Run-of-river hydropower plants (HPPs), dams and weirs pose a particular threat for downstream migrating fish. The migration delay and injury or mortality during turbine or spillway passages contribute to a decline in fish populations worldwide. The overarching goal of this research study is therefore to improve the sustainable and efficient use of hydropower by providing a technical solution for the safe downstream migration of fish at run-of-river HPPs and water intakes with a minimal impact on hydropower production and operation. The focus lies on the design improvement of mechanical behavioural fish guidance structures (FGSs) consisting of vertical bars in combination with a bypass system (BS).
  • Velocity Fields at Horizontal Bar Racks as Fish Guidance Structures
    Item type: Journal Article
    Meister, Julian; Fuchs, Helge; Beck, Claudia; et al. (2020)
    Water
    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.
  • Downstream fish passage at hydropower plants by means of fish guidance structures
    Item type: Conference Paper
    Albayrak, Ismail; Beck, Claudia; Meister, Julian; et al. (2018)
  • Hydraulic and fish-biological performance of fish guidance structures with curved bars
    Item type: Conference Paper
    Beck, Claudia (2019)
    Proceedings of the IAHR World Congress ~ Proceedings of the 38th IAHR World Congress
    Run-of-river hydropower plants pose a particular threat for downstream migrating fish because of high injury and mortality rates during turbine and spillway passages leading to a decline in fish populations worldwide. Fish guidance structures with vertical bars such as angled bar racks combined with a bypass can protect fish and ensure their safe downstream migration. The optimal hydraulic performance of these structures is essential for a sustainable power plant operation and efficient fish guidance. Previous studies indicated that the hydraulic performance of the current angled bar rack designs is insufficient because of high head losses and asymmetric turbine admission flow. To mitigate these issues, a new bar shape of curved cross section was developed. Angled bar racks with novel curved bars, so-called Curved-Bar Racks (CBRs), show an improved hydraulic performance compared to fish guidance structures with straight bars. CBRs reduce the hydraulic head losses on average by a factor of 4.2 as compared to the equivalent angled bar rack configurations with straight bars. Moreover, they promote a flow straightening effect leading to flow conditions favorable for both fish guidance and turbine operation. This research reports the findings of the ethohydraulic experiments on an optimum CBR configuration with two European fish species, namely, the barbel (Barbus barbus), and the spirlin (Alburnoides bipunctatus). The fish swimming behavior at the CBR-bypass system was analyzed with heat maps generated with a 3D fish-tracking software. Since fish react sensitively to spatial velocity gradients, the bypass operation is optimized to maximize the fish guidance efficiency.
  • Fischschutz und Fischabstieg: Neueste Erkenntnisse aus der Forschung
    Item type: Conference Paper
    Meister, Julian; Beck, Claudia; Fuchs, Helge; et al. (2019)
  • Curved-Bar-Rack-Bypass-Systeme für den Fischschutz an Wasserkraftanlagen und Wasserfassungen
    Item type: Journal Article
    Beck, Claudia; Albayrak, Ismail; Leuch, Claudia; et al. (2021)
    WasserWirtschaft
    Ein neuartiger Fischleitrechen mit vertikalen, gebogenen Stäben und anschließendem Bypass-System (BS) stellt eine vielversprechende technische Lösung für den Fischabstieg an Laufwasserkraftwerken dar. Dieses sogenannte Curved-Bar-Rack-Bypass-System (CBR-BS) zeichnet sich durch geringe hydraulische Verluste, eine symmetrische Rechenabströmung und eine hohe Fischleiteffizienz im Labor aus. Dieser Beitrag präsentiert die Forschungsergebnisse der Laborversuche und der numerischen Modellierung zum neu entwickelten CBR-BS.
  • Bemessungsempfehlungen für den Fischschutz mit Horizontalrechen-Bypass-Systemen
    Item type: Journal Article
    Meister, Julian; Beck, Claudia; Albayrak, Ismail; et al. (2021)
    WasserWirtschaft
    Obwohl Horizontalrechen-Bypass-Systeme (HBR-BS) dem Stand der Technik für den Fischschutz und Fischabstieg entsprechen und in den letzten Jahren an vielen europäischen Wasserkraftanlagen installiert wurden, gibt es immer noch diverse Wissenslücken bezüglich der Hydraulik, den betrieblichen Aspekten und des Fischverhaltens. Aus diesem Grund wurden an der Versuchsanstalt für Wasserbau, Hydrologie und Glaziologie (VAW) der ETH Zürich umfangreiche hydraulische und ethohydraulische Untersuchungen durchgeführt. In diesem Beitrag werden die wichtigsten Forschungsresultate der ethohydraulischen Versuche präsentiert und wichtige Bemessungsempfehlungen zusammengefasst, während die hydraulischen Untersuchungen und systematische Verlegungsversuche mit Laub in einem anderen Beitrag in diesem Heft der WasserWirtschaft präsentiert werden.
Publications 1 - 10 of 26