Probing the complexities of optimal flow in open channels: experimental and numerical validation with diversion flow

This study aims to establish the optimal diversion angle for bifurcating channels to minimize separation zone size in the intake channel while maximizing discharge in the bifurcating channel through experimental and numerical investigations. The study successfully accomplished its goals by employing the Flow-3D 11.0.4 software. The software was utilized to examine the flow diversion into bifurcating channels with various diversion angles, including 900 degrees, 750 degrees, 600 degrees, 450 degrees, 300 degrees, 250 degrees, 200 degrees and 150 degrees. The experimental investigation has confirmed the theoretical predictions regarding the expected flow characteristics. The conclusive findings demonstrated that the diverted flow is most effectively impacted by a diversion angle of 25 degrees. The study provided findings for various discharges flowing (12.3 and 17 L/s); a total of 95 runs were performed, and investigations revealed that the branching discharge depends on several interconnected parameters. It rises with an increase in the depth ratio. In subcritical flow, the main channel always has a lower water depth than the branch channel. The flowing diversion to the branch channel causes a reduction in water depth downstream of the main channel. The study found that the optimal angle for branching was 25 degrees.