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- Bin Asad, S M Sayeed, et al.
(författare)
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A Review of Particle Image Velocimetry for Fish Migration
- 2016
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Ingår i: World Journal of Mechanics. - : Scientific Research Publishing, Inc.. - 2160-049X .- 2160-0503. ; 6:4, s. 131-149
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the flow characteristic in fishways is crucial for efficient fish migration. Flow characteristic measurements can generally provide quantitative information of velocity distributions in such passages; Particle Image Velocimetry (PIV) has become one of the most versatile techniques to disclose flow fields in general and in fishways, in particular. This paper firstly gives an overview of fish migration along with fish ladders and then the application of PIV measurements on the fish migration process. The overview shows that the quantitative and detailed turbulent flow information in fish ladders obtained by PIV is critical for analyzing turbulent properties andvalidating numerical results.
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| 3. |
- Bin Asad, S M Sayeed
(författare)
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Laser-based Measurements connected to Fish Migration
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hydropower is one of the main sources for Sweden’s energy, which is clean and renewable. It is a clean energy source because no fuels are burned which does not pollute the air and it is a renewable energy source as it only uses natural water cycle for generating energy. However, hydropower has some consequences in nature, such as creating dams in rivers and changing water flow directions, which lead to some problems for migrating fishes. These fish migration problems are mostly studied from a biological point of view but more detailed studies are required from a fundamental fluid mechanics point of view. Fish migrates when ecological imbalance is created and one of the reasons for this imbalance is having dams for hydropower. Some dams have fishways or fish ladders to allow fish to migrate past the dam and during swimming or passing this fishway or fish ladder, fish has to tackle some sort of flow obstructions like, turbine intakes, stones and concrete structures etc. Fluid flow characteristics in fish ladders or fishways during fish migration is crucial for designing effective fishways to migrate fishes effectively. Flow characteristic measurements can provide quantitative information of the velocity distribution in fish ladders, which has strong correlation with the attraction of of fish. Recent research suggests that turbulence also has a large effect on fish migration. This is why obtaining flow information from well-defined turbulent flows, such as flow past cylindrical objects is the prime aim of these measurements.Particle Image Velocimetry (PIV) and Laser Doppler Velocimetry (LDV) have become the most popular and promising techniques for these types of non-contact measurements. PIV techniques are used to visualize and measure the flow characteristic in a selected area while LDV techniques are suited for point-based measurement. The works included in this thesis are reviewing PIV techniques previously used in fish movement related studies, LDV measurements both at upstream (bow wake) and downstream wake of cylindrical obstructions and finally Computational Fluid Dynamics (CFD) for validation of experimental measurements. The results find relatively acceptable agreement between CFD and experiments with some disparities.
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| 4. |
- Bin Asad, S M Sayeed, 1985-, et al.
(författare)
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Velocity distribution measurements in a fishway like open channel by Laser Doppler Anemometry (LDA)
- 2016
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Konferensbidrag (refereegranskat)abstract
- Experiments in an open channel flume with placing a vertical half cylinder barrier have been performed in order to investigate how the upstream velocity profiles are affected by a barrier. An experimental technique using Laser Doppler Velocimetry (LDV) was adopted to measure these velocity distributions in the channel for four different discharge rates. Velocity profiles were measured very close to wall and at 25, 50 and 100 mm upstream of the cylinder wall. For comparing these profiles with well-known logarithmic velocity profiles, velocity profiles were also measured in smooth open channel flow for all same four discharge rates. The results indicate that regaining the logarithmic velocity profiles upstream of the half cylindrical barrier occurs at 100 mm upstream of the cylinder wall.
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