坡道宽度变化的影响影响到影响下游迁徙鱼的溢流的液压条件
Seyed Sobhan Aleyasin1, Sedem Kumahor2, Mark Francis Tachie2
1Department of Mechanical Engineering, University of Manitoba, Winnipeg, MB, Canada. aleyasss@myumanitoba.ca.
Scientific reports
|March 19, 2025
概括
一个45o上游溢流道坡道.
科学领域:
- 流体动力学 流体动力学
- 鱼类的迁徙 鱼类的迁徙
背景情况:
- 鱼类迁徙路径对水生生态系统至关重要.
- 溢出坡被用来引导鱼下游.
- 动荡的流动特征影响鱼类的行为.
研究的目的:
- 为了研究上游溢流坡宽度比对流的影响.
- 为了确定指导鱼类下游的最佳坡道设计.
主要方法:
- 使用45o上游溢流坡道进行实验调查,其跨度宽度比率不同 (10%,25%,50%).
- 用于捕捉速度场的粒子图像速度测量 (PIV) 系统.
- 分析平均速度,空间速度梯度,雷诺兹应力和动动能.
主要成果:
- 流量拓在很大程度上受到斜坡宽度比的影响.
- 观察到的循环回收区域位于溢出通道脚部附近和坡道上游.
- 10%的坡道宽度比率为下游迁徙鱼类创造了更有利的途径,因为速度和流较低.
结论:
- 部分宽度的溢流坡道可以有效地引导鱼类.
- 10%的坡道宽度比率提供了一个有希望的,具有成本效益的解决方案.
- 从部分宽度坡道的跨度不均性可能会影响靠近河床的某些鱼类.
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