Numerical simulation of turbulent ow over labyrinth spillways/weirs and corresponding discharge coefficient and efficiency

Labyrinth spillway has become an appropriate choice to increase an existing spillwayʹs capacity. Thus, it is necessary to understand the hydraulic performance of labyrinth spillways/weirs. This paper numerically solves turbulent ow over labyrinth spillways/weirs and determines the discharge coecients. Reynolds governing equations, turbulence k ?? " model, and the Volume Of Fluid (VOF) model are numerically solved to dene pressure, velocity, and the free surface ow proles. The numerical results are comparable to those obtained from physical modeling with maximum 6.43% error relative to results of physical modeling. Present study indicates that numerical simulation can be used to supplement physical modeling. Thus, by using numerical solutions, the site specics of the spillway which are often dierent from the conditions of design curves can be investigated. Also, the eect of dierent shapes of apex on discharge capacity of the labyrinth spillway is investigated in this study. The analyses show that labyrinth spillways with round apex shape are the most ecient spillways. Numerical determination of free water surface is presented and discussed, which is helpful for optimum design of stilling basin and leading walls.