Measured and simulated flow downstream of the submerged sluice gate

In this study, turbulent flow downstream of the submerged sluice gate was investigated experimentally and numerically. Experimental studies were conducted in a laboratory flume to measure the flow velocities and turbulence characteristics. Three‐dimensional computational fluid dynamics (CFD) simulation was performed to investigate the flow structure downstream of the sluice gate. It is found that the flow downstream of the submerged sluice gate is highly three‐dimensional and unsteady in nature because of the interaction of mean flow and recirculation flow. The three‐dimensional simulation results indicate that the interacted flow triggers the formation of two corner vortices. Secondary velocities associated with the free surface vortices are found to be about 6% of the mean jet velocity at the inlet, which is significant for the river bank erosion. Vortex induced free surface fluctuations were also observed in the vicinity of the submerged gate.