Flow pattern in fish passes: comparison of numerical models

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Didier Bousmar, Zhonghua Li, Adeline Baugnée, Jean-Christophe DeGreef

Friday 3 july 2015

12:54 - 12:57h at North America (level 0)

Themes: (T) Hydro-environment, (ST) Ecohydraulics and ecohydrology, Poster pitches

Parallel session: Poster pitches: 15F. Environment - Ecohydraulic

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Flow pattern in vertical slot fish passes is investigated using numerical models. Site and construction constrains sometimes jeopardise the use of standard basin shape as taken from literature. It is then necessary to verify that the resulting flow pattern still enables comfortable fish passage for the target species. Numerical modelling should be an appropriate tool for such investigation, provided flow recirculation patterns and turbulence levels are correctly reproduced. In the present paper, three numerical models are compared to physical model data for two fish passes. The investigated fish passes are located at Rivière weir on River Meuse, Belgium, and at Danba dam on River Daduhe, China, and are modelled at scale 1/5 and 1/2.5, respectively. One depth-averaged numerical model and two three-dimensional models are used: Telemac 2D, Telemac 3D and Fluent. Different modelling approaches are tested: modelling of the whole fish pass or of selected basins; different turbulence models; etc. Computed velocity fields, recirculation zones and turbulence levels are compared between numerical models and with physical model data.