Numerical and Physical Modelling to Dissipate the Flow Energy of Spillway Using Multiple Rows of Chute Blocks

Abstract

Physical and Numerical models have been used to maximize the dissipation of flow energy of a sipllway, and to guarantee the occurring of hydraulic jump in the stilling basin in shorter length, and to find the right model to simulate turbulent flow properties using the techniques of Computational Fluid Dynamics (CFD). 5 models have been tested which they had different rows of chute blocks. For each, 6 slopes of chute were examined, 1:0.8, 1:1.0, 1:1.2, 1:1.4, 1:1.6, 1:1.8, with 10 cm of tail water. Physical models were emplemnted to represent a sucssecfully models that compared with the theoretical model in a slope 1:1.2 for chute. Using the RNG & K-є as a turbulent theoretical model and a non uniform distribution of the mesh led to sucssesfully simulating the stream lines, velosities and shape of hydraulic jumps and Froude numbers. Using four rows of choute blocks at the end of the chute near the edge is the best design to dissipate the energy, which was 61.9%, and for spillway slope of 1:0.8, while the percentage of energy dissipation that depending reducing the distance of the roller jump and reducing the distance of the supercritical flow was laid between (17.8, 94.8)%, respectively, when the spillway slope is 1:1.0.