scholarly journals Swimming Behavior of Downstream Moving Fish at Innovative Curved-Bar Rack Bypass Systems for Fish Protection at Water Intakes

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3244
Author(s):  
Claudia Beck ◽  
Ismail Albayrak ◽  
Julian Meister ◽  
Armin Peter ◽  
Oliver M. Selz ◽  
...  
Keyword(s):  
Fish Species ◽  
Flow Direction ◽  
Cost Effective ◽  
Technical Solution ◽  
Velocity Increase ◽  
Hydropower Plants ◽  
Downstream Flow ◽  
High Fish ◽  
Fish Protection ◽  
Run Of River

New types of fish guidance structures with vertical curved bars and a subsequent bypass system represent a promising technical solution for the protection and guidance of downstream moving fish at run-of-river hydropower plants and water intakes. These so-called “curved-bar rack bypass systems” (CBR-BSs) function as a mechanical behavioral barrier and are characterized by low hydraulic losses, a symmetrical downstream flow field and an overall high fish guidance efficiency in the laboratory for a wide array of European freshwater fish species. This paper presents the results of the hydraulic and live-fish laboratory tests of an optimized CBR-BS configuration with a bar spacing of 50 mm and 30° rack angle to the flow direction. The tests were conducted with six different fish species in an ethohydraulic laboratory flume at different approach flows (0.5 m/s, 0.7 m/s) and different bypass entrance velocities (0.6–1.0 m/s). A numerical model was used to simulate the flow fields in the CBR-BS in order to link the fish behavior to the hydrodynamic cues created by the CBR-BS. Lower approach flow velocities decreased the hydraulic cues of the CBR, which led to more rack passages. A 20% velocity increase towards the bypass entrance significantly increased the fish guidance efficiency compared to a 40% velocity increase. The tested CBR-BS resulted in overall higher interspecies fish protection and guidance efficiencies compared to the more commonly applied horizontal-bar rack with a narrow bar spacing of 20 mm. Recommendations for a sustainable and cost-effective application of CBR-BSs are given.

scholarly journals Ethohydraulic experiments on the fish protection potential of the hybrid system FishProtector at hydropower plants

2021 ◽  
Vol 171 ◽  
pp. 106370
Author(s):  
Ruben Tutzer ◽  
Simon Röck ◽  
Janette Walde ◽  
Bernhard Zeiringer ◽  
Günther Unfer ◽  
...  
Keyword(s):  
Hybrid System ◽  
Hydropower Plants ◽  
Protection Potential ◽  
Fish Protection

Effects of run‐of‐river hydropower plants on fish communities in montane stream ecosystems in Serbia

2021 ◽  
Author(s):  
Predrag Simonović ◽  
Ratko Ristić ◽  
Vukašin Milčanović ◽  
Siniša Polovina ◽  
Ivan Malušević ◽  
...  
Keyword(s):  
Fish Communities ◽  
Stream Ecosystems ◽  
Hydropower Plants ◽  
Run Of River

Vortices' Characteristics to Explain the Flange Height Effects on the Aerodynamic Performances of a Diffuser Augmented Wind Turbine

2016 ◽  
Vol 138 (6) ◽  
Author(s):  
Rym Chaker ◽  
Mouldi Kardous ◽  
Mahmoud Chouchen ◽  
Fethi Aloui ◽  
Sassi Ben Nasrallah
Keyword(s):  
Wind Velocity ◽  
Particle Image ◽  
Flow Direction ◽  
Pressure Coefficient ◽  
Inlet Section ◽  
Wind Tunnel Experiments ◽  
Piv Measurements ◽  
Velocity Increase ◽  
Image Velocimetry ◽  
Aerodynamic Performances

Flange height is between the geometric features that contribute efficiently to improve the diffuser aerodynamic performances. Results obtained from wind tunnel experiments, particle image velocimetry (PIV) measurements, and numerical simulations reveal that at the diffuser inlet section, the wind velocity increases as the flange height increases. Nevertheless, there is an optimal ratio (flange height/inlet section diameter, Hopt/Da ≈ 0.15) beyond it, the flange height effect on the velocity increase diminishes. This behavior can be explained by both the positions of the two contra-rotating vortices generated downstream of the diffuser and the pressure coefficient at their centers. Indeed, it was found that, as the flange height increases, the two vortices move away from each other in the flow direction and since the flange height exceeds (Hopt/Da), they became too distant from each other and from the flange. While the pressure coefficients at the vortices' centers increase with (H/Da), attain a maximum when (Hopt/Da) is reached, and then decrease. This suggests that the wind velocity increase depends on the pressure coefficient at the vortices' centers. Therefore, it depends on the vortices' locations which are in turn controlled by the flange height. In practice, this means that the diffuser could be more efficient if equipped with a control system able to hold the vortices too near from the flange.

GEOLOGICAL STORAGE OF CARBON DIOXIDE: MODELLING THE EARLY CRETACEOUS SUCCESSION IN THE BARROW SUB-BASIN, NORTHWEST AUSTRALIA

2004 ◽  
Vol 44 (1) ◽  
pp. 653 ◽  
Author(s):  
C.M. Gibson-Poole ◽  
J.E. Streit ◽  
S.C. Lang ◽  
A.L. Hennig ◽  
C.J. Otto
Keyword(s):  
Storage Capacity ◽  
Flow Direction ◽  
Co2 Storage ◽  
Column Height ◽  
Co2 Injection ◽  
Technical Solution ◽  
Exit Point ◽  
Geological Storage ◽  
Migration Pathways ◽  
Northwest Australia

Potential sites for geological storage of CO2 require detailed assessment of storage capacity, containment potential and migration pathways. A possible candidate is the Flag Sandstone of the Barrow Sub-basin, northwest Australia, sealed by the Muderong Shale. The Flag Sandstone consists of a series of stacked, amalgamated, basin floor fan lobes with good lateral interconnectivity. The main reservoir sandstones have high reservoir quality with an average porosity of 21% and an average permeability of about 1,250 mD. The Muderong Shale has excellent seal capacity, with the potential to withhold an average CO2 column height of 750 m. Other containment issues were addressed by in situ stress and fault stability analysis. An average orientation of 095°N for the maximum horizontal stress was estimated. The stress regime is strike-slip at the likely injection depth (below 1,800 m). Most of the major faults in the study area have east-northeast to northeast trends and failure plots indicate that some of these faults may be reactivated if CO2 injection pressures are not monitored closely. Where average fault dips are known, maximum sustainable formation pressures were estimated to be less than 27 MPa at 2 km depth. Hydrodynamic modelling indicated that the pre-production regional formation water flow direction was from the sub-basin margins towards the centre, with an exit point to the southwest. However, this flow direction and rate have been altered by a hydraulic low in the eastern part of the sub-basin due to hydrocarbon production. The integrated site analysis indicates a potential CO2 storage capacity in the order of thousands of Mtonnes. Such capacity for geological storage could provide a technical solution for reducing greenhouse gas emissions.

scholarly journals Habitat Use by Pseudochondrostoma duriense and Squalius carolitertii Downstream of a Small-Scale Hydropower Plant

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2522
Author(s):  
Isabel Boavida ◽  
Filipa Ambrósio ◽  
Maria João Costa ◽  
Ana Quaresma ◽  
Maria Manuela Portela ◽  
...  
Keyword(s):  
Habitat Use ◽  
Fish Species ◽  
Hydropower Plant ◽  
Mitigation Measures ◽  
Small Scale ◽  
The North ◽  
Reduce Energy Expenditure ◽  
Hydropower Plants ◽  
River Reach ◽  
Flowing Waters

Downstream of small-scale hydropower plants (SHPs), the intensity, frequency and persistence of hydropeaking events often cause an intolerable stress on fish of all life stages. Rapid increases in flow velocity result in fish avoiding unstable habitats and seeking refuge to reduce energy expenditure. To understand fish movements and the habitat use of native Iberian cyprinids in a high-gradient peaking river, 77 individuals were PIT tagged downstream of Bragado SHP in the North of Portugal. Tagged fish species included Pseudochondrostoma duriense and Squalius carolitertii. Fish positions were recorded manually on two different occasions: during hydropeaking events (HP) and without hydropeaking events (NHP). From the 77 tagged fish, we were able to record habitat use for 33 individuals (20 P. duriense and 13 S. carolitertii) in a total of 125 relocations. Fish species were distributed along the river reach with high density in the upstream area in the vicinity of the SHP tailrace, in particular during HP. Fish locations were associated with velocity for P. duriense and S. carolitertii. The latter tended to use faster flowing waters than P. duriense. Our findings on the habitat use in peaking rivers are a valuable tool to help in the selection and design of mitigation measures.

Flow regime aspects in determining environmental flows and maximising energy production at run-of-river hydropower plants

2019 ◽  
Vol 256 ◽  
pp. 113980 ◽  
Author(s):  
Alban Kuriqi ◽  
António N. Pinheiro ◽  
Alvaro Sordo-Ward ◽  
Luis Garrote
Keyword(s):  
Flow Regime ◽  
Energy Production ◽  
Environmental Flows ◽  
Hydropower Plants ◽  
Run Of River

LDV Measurements and Investigation of Flow Field Through Radial Turbine Guide Vanes

1991 ◽  
Vol 113 (4) ◽  
pp. 660-667
Author(s):  
Hasan Eroglu ◽  
Widen Tabakoff
Keyword(s):  
Flow Field ◽  
Flow Direction ◽  
Mean Flow ◽  
Flow Rates ◽  
Radial Turbine ◽  
Contour Plots ◽  
Mass Flow Rates ◽  
Flow Turbulence ◽  
Downstream Flow ◽  
Nozzle Blade

The results of LDV measurements and investigation of the detailed flow field in a radial inflow turbine nozzle are presented. The flow velocities were measured at upstream, inside and downstream of the nozzle blades for two different mass flow rates, using a three-component LDV system. Results are presented as contour plots of mean velocities, flow angles, and turbulence intensities. The flow field inside the nozzle blade passages was found to be influenced by the upstream scroll geometry. The flow turbulence increased in the downstream flow direction. The LDV mean flow results on the blade-to-blade midspan plane which is parallel to the end walls were also compared with an inviscid, “panel method” solution.

THE INFLUENCE OF OPERATION CONDITIONS OF HYDROELECTRIC POWER PLANTS THE CHOICE OF THE MAIN PARAMETERS OF THE SUCTION PIPES

2015 ◽  
Vol 5 (4) ◽  
pp. 86-92 ◽  
Author(s):  
Mikhail Ivanovich BALZANNIKOV
Keyword(s):  
Power Plants ◽  
Draft Tube ◽  
Operating Conditions ◽  
Hydroelectric Power Station ◽  
Geometrical Parameters ◽  
Hydroelectric Power ◽  
Operation Conditions ◽  
Hydropower Plants ◽  
Large Water ◽  
Run Of River

Considered run-of-river hydropower plants (HPP). Notes the importance of technical-economic calculations in the justifi cation of large water-conducting elements of the path these types of HPP. The methodology of economic substantiation of the expediency of increasing the length of the draft tube. Using the technique of the calculations for lowpressure hydroelectric run-of-river type. The results of the analysis of the influence of the operating conditions of the hydroelectric power station on basic geometrical parameters of draft tube.

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