当前位置: X-MOL 学术River Res. Appl. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Hybrid modelling of low velocity zones in an asymmetrical channel with sidewall longitudinal rib to assist fish passage
River Research and Applications ( IF 2.2 ) Pub Date : 2020-02-25 , DOI: 10.1002/rra.3600
Pedro X. Sanchez 1 , Xinqian Leng 1 , Johann Von Brandis‐Martini 1 , Hubert Chanson 1
Affiliation  

Channels with longitudinal beams have been studied for decades in chemical engineering, environmental and sanitary engineering, aeronautics, astronautics, biology and geology. In the current study, a combination of physical and numerical Computational Fluid Dynamics (CFD) modelling was undertaken to test whether an asymmetrical channel equipped with a sidewall longitudinal rib could provide flow conditions conducive to upstream fish passage. The study focused on small‐bodied fish and juveniles of larger fish, typically less than 100 mm in total length. A detailed hydrodynamic study was conducted in an asymmetrical rectangular channel equipped with a sidewall square rib in a culvert barrel channel. Both free‐surface velocity and boundary shear stress measurements showed strong secondary currents of Prandtl's second kind. The channel asymmetry contributed to intense secondary motion, associated with turbulent dissipation. The channel design provided a small well‐defined highly turbulent low‐velocity zone beneath the rib. In the context of hydraulic structure designs, uttermost care must be considered because of manufacturing, installation and operational practices. In many instances, alternative engineering designs with small baffles and asymmetrical appurtenance should be preferred to assist with fish passage in hydraulic structures.

中文翻译:

具有侧壁纵向肋以帮助鱼通过的非对称通道中低速区的混合建模

几十年来,化学工程、环境和卫生工程、航空、航天、生物学和地质学对具有纵梁的通道进行了研究。在当前的研究中,结合物理和数值计算流体动力学 (CFD) 建模来测试配备侧壁纵向肋的非对称通道是否可以提供有利于上游鱼类通过的流动条件。该研究侧重于体型较小的鱼和较大鱼的幼鱼,通常总长度小于 100 毫米。详细的流体动力学研究是在一个不对称的矩形通道中进行的,该通道在涵洞桶通道中配备了侧壁方形肋。自由表面速度和边界剪应力测量结果均显示出普朗特第二类强二次流。通道不对称导致强烈的二次运动,与湍流耗散相关。通道设计在肋下方提供了一个小的、明确的高湍流低速区。在水工结构设计的背景下,由于制造、安装和操作实践,必须非常小心。在许多情况下,应首选带有小挡板和不对称附件的替代工程设计,以帮助鱼在水利结构中通过。
更新日期:2020-02-25
down
wechat
bug