Numerical Investigation of Flow Division at Lateral Diversions

This study numerically investigates the flow division at lateral diversions, focusing on the influence of the diversion angle and the ratio of channel widths on flow characteristics and discharge distribution. A total of 68 simulations were performed using FLOW-3D HYDRO 2022R1 software with a Large Eddy Simulation turbulence model. The investigation covered diversion angles of 30°, 45°, 60°, and 90°, combined with width ratios of 0.25, 0.50, and 1.00, under a wide range of upstream and downstream flow parameters. The flow fields were analyzed using cross-sections in both channels; the change in flow depths and velocity fields were evaluated together with organized flow structures. Streamline analyses were performed and three new empirical equations were proposed to predict the width of the divided flow and the discharge distribution in the bifurcation. Finally, the performance of existing equations previously proposed in the literature were assessed against the simulation results.