The Effect of Froude Number on Flow Field of U-Shaped Channel Along a Side Weir in Supercritical Flow Regime

Abstract

In this study, turbulence of the flow field as well as the flow free surface in a U-shaped channel located along a side weir under supercritical flow conditions are simulated using the RNG k-ε turbulence model and VOF scheme. Comparison of the numerical and laboratory results shows that the numerical model simulates the free surface and characteristics of the flow field with acceptable accuracy. Then, the effects of the upstream Froude number of the side weir on the flow pattern of the main channel are investigated. For all Froude numbers, in the vicinity of the inner bank a free surface drop occurs at the beginning of the side weir upstream, and a surface jump is formed at the final quarter of the side weir length. Across the surface jump, the kinematic energy of water increases and the potential energy decreases. The dividing stream surface and the stagnation zone dimensions increase as the Froude number increases.