Comprehensive study of the hydrodynamic effects of weirs installed in the bypass of bar rack systems to better guide downstream migrating fish
Bibliographic record
Abstract
Turbulent flows are investigated in the bypass of a bar rack system to understand the effects of weirs placed at the bypass entrance on hydraulic conditions used to guide fish moving downstream. Three test cases were studied: (a) no weir (reference case), (b) arc-shaped weir and (c) triangular weir. A stereo particle image velocimetry system was employed to acquire the three velocity components in the mid-plane of the bypass and examine various statistics including mean velocities, Reynolds stresses, turbulent kinetic energy as well as turbulence eddies and swirling strength. The weirs deflect the flow away from the channel bed due to the blockage effect and increase the bypass velocity significantly, though remains under the suggested critical value of 1 m s−1 when the approach velocity was 0.38 m s−1. In the wake region of the triangular weir, a distinct recirculation bubble forms which may negatively affect fish migration. There is an increase in the level of Reynolds stresses and turbulent kinetic energy in the upstream vicinity of the weirs and the shear layers issuing from their tips. It is shown that the topology of the turbulence eddies is greatly modified by the weirs which can more readily assist fish guidance toward the bypass. Also, the swirling strength of the turbulence eddies behind the triangular weir is more pronounced compared to the arc-shaped weir. For the reference case, the swirling strength of the eddies is the weakest.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".