Numerical simulation study on hydraulic characteristics of weir hole-vertical slot fishway

In order to explore the influence of the change of vertical slot fishway structure on the hydraulic characteristics to improve the hydraulic conditions of the fishway, this study sued the RNG k-ε turbulence model to simulate the flow conditions in the pool chamber of different weir hole-vertical slot combination fishways, and investigated the distribution of the flow field, the maximum slot flow velocity, the turbulence energy and other hydraulic properties, and analyzed the influence of the hydraulic characteristics of fishways on the migration of fish. The study showed that in the weir hole-vertical slot fishway, the flow velocity of the water decreased as a whole, the maximum flow velocity of the vertical slot decreased to 1.10 m/s, and at the same time, the area of the reflux area decreased. Compared with the conventional vertical slot fishway, the area suitable for fish upstreaming increased from 41.05% to 50.93%, which was more favorable for fish migration upstreaming.