LAUSR

Abstract Side weirs are hydraulic structures that are used in irrigation and drainage channels, flood control systems, and wastewater collection networks to divert the flow, isolate the sedimentation, and reduce the bed loads. Labyrinth side weirs are a type of side weirs with a higher discharge coefficient compared to the traditional side weirs. During the last decade, these weirs have been the interest of different researchers. In this study, triangular labyrinth side weirs with the groups of guide vanes were modeled numerically using OpenFOAM software. The free surface of subcritical approach flow over the labyrinth side weirs was modeled using Volume of Fluids method. The standard k-ε turbulence model was applied to calculate the flow characteristics. The results of the numerical model are compared well with those of the available experimental data. According to the results, the maximum discharge coefficient of a side weir is obtained when the vane plates are located perpendicular to the flow direction at the downstream end of the weirs across the main channel.