Optimization of the Flow Conditions in the Spawning Grounds of the Chinese Sturgeon (Acipenser Sinensis) Through Gezhouba Dam Generating Units

Abstract Chinese sturgeon (Acipenser sinensis) is a critically endangered species, and waters downstream from Gezhouba Dam are the only known spawning grounds. To optimize the velocity conditions in the spawning grounds by controlling the opening mode of Gezhouba Dam generator units, a mathematical model of Chinese sturgeon spawning grounds was established in FLOW-3D. The model was evaluated with velocity measurements, and the results was determined to be in good agreement. By inverting the 2016-2019 field monitoring results, the model shows that the preferred velocity range for Chinese sturgeon spawning is 0.6-1.5 m/s. Velocity fields of different opening modes of the generator units were simulated with identical discharge. The suitable-velocity area was maximal when all units of Dajiang Plant of Gezhouba Dam were open. For discharges below 12000 m3/s, most of the area was suitable; for discharges above 12000 m3/s, the suitable area rapidly decreased with increasing discharge. A comparison of suitable areas under high-flow showed that at discharges of 12000~15000 m3/s, opening 11~13 units on the left side was optimal. For discharges above 15000 m3/s, all units should be open. We used these results to recommend a new operation scheme to support the conservation of Chinese sturgeon.

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Optimization of the flow conditions in the spawning ground of the Chinese sturgeon (Acipenser sinensis) through Gezhouba Dam generating units

Scientific Reports ◽

10.1038/s41598-021-93903-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Anyang Huang ◽

Jinzhong Yao ◽

Jiazhi Zhu ◽

Xingchen Gao ◽

Wei Jiang

Keyword(s):

Spawning Ground ◽

Chinese Sturgeon ◽

Flow Conditions ◽

Velocity Measurements ◽

Acipenser Sinensis ◽

Critically Endangered Species ◽

Gezhouba Dam ◽

Opening Mode ◽

Suitable Area ◽

Good Agreement

AbstractChinese sturgeon (Acipenser sinensis) is a critically endangered species, and waters downstream from Gezhouba Dam are the only known spawning ground. To optimize the velocity conditions in the spawning ground by controlling the opening mode of Gezhouba Dam generator units, a mathematical model of Chinese sturgeon spawning ground was established in FLOW-3D. The model was evaluated with velocity measurements, and the results were determined to be in good agreement. By inverting the 2016–2019 field monitoring results, the model shows that the preferred velocity range for Chinese sturgeon spawning is 0.6–1.5 m/s. Velocity fields of different opening modes of the generator units were simulated with identical discharge. The suitable-velocity area was maximal when all units of Dajiang Plant of Gezhouba Dam were open. For discharges below 12,000 m3/s, most of the area was suitable; for discharges above 12,000 m3/s, the suitable area rapidly decreased with increasing discharge. A comparison of suitable areas under high-flow showed that at discharges of 12,000–15,000 m3/s, opening 11–13 units on the left side was optimal. For discharges above 15,000 m3/s, all units should be open. We used these results to recommend a new operation scheme to support the conservation of Chinese sturgeon.

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The optimization of flow conditions in the spawning grounds of the Chinese sturgeon (Acipenser sinensis) through Gezhouba Dam units

10.22541/au.160157550.00590919 ◽

2020 ◽

Author(s):

Anyang Huang ◽

Jinzhong Yao ◽

Jiazhi Zhu ◽

Xingchen Gao ◽

Wei Jiang

Keyword(s):

Chinese Sturgeon ◽

Flow Conditions ◽

Spawning Grounds ◽

Acipenser Sinensis ◽

Gezhouba Dam

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Structural and quality changes in the spawning stock of the Chinese sturgeon Acipenser sinensis below the Gezhouba Dam (Yangtze River)

Journal of Applied Ichthyology ◽

10.1111/j.1439-0426.2007.00937.x ◽

2006 ◽

Vol 22 (s1) ◽

pp. 111-115 ◽

Cited By ~ 5

Author(s):

Xiao Hui ◽

Liu Denghong ◽

Tang Daming ◽

Guo Bofu

Keyword(s):

Yangtze River ◽

Quality Changes ◽

Chinese Sturgeon ◽

Acipenser Sinensis ◽

Gezhouba Dam ◽

Spawning Stock

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Numerical Simulations of Flow in Cerebral Aneurysms: Comparison of CFD Results and In Vivo MRI Measurements

Journal of Biomechanical Engineering ◽

10.1115/1.2970056 ◽

2008 ◽

Vol 130 (5) ◽

Cited By ~ 56

Author(s):

Vitaliy L. Rayz ◽

Loic Boussel ◽

Gabriel Acevedo-Bolton ◽

Alastair J. Martin ◽

William L. Young ◽

...

Keyword(s):

Flow Fields ◽

Patient Specific ◽

Flow Ratio ◽

Flow Conditions ◽

Velocity Measurements ◽

Cfd Simulations ◽

Specific Flow ◽

Inlet Flow ◽

Good Agreement

Computational fluid dynamics (CFD) methods can be used to compute the velocity field in patient-specific vascular geometries for pulsatile physiological flow. Those simulations require geometric and hemodynamic boundary values. The purpose of this study is to demonstrate that CFD models constructed from patient-specific magnetic resonance (MR) angiography and velocimetry data predict flow fields that are in good agreement with in vivo measurements and therefore can provide valuable information for clinicians. The effect of the inlet flow rate conditions on calculated velocity fields was investigated. We assessed the internal consistency of our approach by comparing CFD predictions of the in-plane velocity field to the corresponding in vivo MR velocimetry measurements. Patient-specific surface models of four basilar artery aneurysms were constructed from contrast-enhanced MR angiography data. CFD simulations were carried out in those models using patient-specific flow conditions extracted from MR velocity measurements of flow in the inlet vessels. The simulation results computed for slices through the vasculature of interest were compared with in-plane velocity measurements acquired with phase-contrast MR imaging in vivo. The sensitivity of the flow fields to inlet flow ratio variations was assessed by simulating five different inlet flow scenarios for each of the basilar aneurysm models. In the majority of cases, altering the inlet flow ratio caused major changes in the flow fields predicted in the aneurysm. A good agreement was found between the flow fields measured in vivo using the in-plane MR velocimetry technique and those predicted with CFD simulations. The study serves to demonstrate the consistency and reliability of both MR imaging and numerical modeling methods. The results demonstrate the clinical relevance of computational models and suggest that realistic patient-specific flow conditions are required for numerical simulations of the flow in aneurysmal blood vessels.

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Electrical conductivity of low-pressure shock-ionized argon

Journal of Fluid Mechanics ◽

10.1017/s0022112063001233 ◽

1963 ◽

Vol 17 (2) ◽

pp. 182-192 ◽

Cited By ~ 6

Author(s):

P. R. Smy ◽

H. S. Driver

Keyword(s):

Electrical Conductivity ◽

Shock Tube ◽

Plasma Radiation ◽

Conductivity Measurements ◽

Flow Conditions ◽

Velocity Measurements ◽

Pressure Shock ◽

Ionized Gas ◽

Order Of Magnitude ◽

Good Agreement

The electrical conductivity of shock-ionized argon produced in an electromagnetic shock tube of low attenuation has been measured at shock speeds of March 10–33, with initial pressures of 0·01–2·0 mm Hg. These measurements extend considerably the range of previous measurements performed with pressure-driven shock tubes. With the higher initial pressures or at the highest Mach numbers the measured conductivity is in good agreement with the previous measurements and with the Spitzer–Harm (1953) formula for the conductivity of a fully ionized gas. With the lower initial pressures (which have not previously been investigated) and at the lower March numbers the conductivity falls to less than half of the Spitzer-Harm value. Order-of-magnitude calculations show that diffusion of atoms, and heat conduction by the plasma atoms from the plasma to the shock-tube walls, can cause appreciable plasma cooling (and hence a reduction of the electrical conductivity) with the lowest initial pressures. This mechanism in conjunction with non-attainment of equilibrium ionization appears to explain the observed diminution in conductivity at the lowest pressures, but not the reduced conductivity at the medium pressures.Induced e.m.f. flow-velocity measurements indicate steady-flow conditions in the shock tube while photomultiplier measurements of the plasma radiation indicate that the column of shock-heated gas is 10–20 cm long; this latter figure is supported by the conductivity measurements. The fact that the length of the shock-heated gas column is not drastically shortened at low initial pressures in constrast to the work of Duff (1959), Roshko (1960) and Hooker (1961) is attributed to the fact that in this experiment both driver and driven gases are at high temperature.

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