Experiment-Based CFD Simulation of Flow Pattern at Open-Channel Junctions

Abstract

This paper proposes a numerical 3D flow pattern at the 90° equal-width open-channel junction. The Reynolds stress turbulent model (RSM) is applied to simulate the turbulent flow which is analyzed as a one-phase steady state. The Shumate’s experimental findings are used to test the validity of developed numerical model. Comparison of the simulation results and the experimental data has indicated a close proximity between the flow patterns of the two sets. The average prediction error also showed a range between 3.5 and 10%. Effects of the discharge ratio on the separation zone characteristics have illustrated an inverse relation, where an increase in discharge ratio will entail a decrease in the length and width of the separation zone. The shape index of separation zone has an average value 0.18. Comparison analysis further revealed that the increase in the discharge ratio will lead to a decrease in the maximum value of the bed shear stress. In addition, it clearly provides a powerful numerical model for the flow pattern analysis.