Experimental study and numerical simulation for the flow through a vertical gated spillway

Abstract

    The flow through vertical gated spillways is a rapidly varied flow with highly curvilinear streamlines. The behavior of this flow can be investigated numerically in the reasonable time and expense. In this study, some hydraulic characteristics of this type of flow were evaluated by using a commercial computational fluid dynamics (CFD) packages, namely, the Ansys/Fluent. Two turbulence models, namely, the Realizable and Reynolds stress model (RSM) were applied to simulate this type of flow for both 2-D and 3-D models. The experimental data, which were conducted by the authors in the Hydraulic Structures Laboratory at the National University of Civil Engineering (NUCE), Vietnam, were used to validate the numerical simulation. The results show that these turbulence models could be applied to the analysis of the hydraulic performances for the flow in this field. The water surface profiles and the discharge were predicted within an accuracy range of +0.48  7.29%. Additionally, some 3-D vertical gated spillway models were performed to investigate the effect of side contraction on the discharge capacity due to piers and abutments. These results indicate that there is a good approximation for the effective length formula while using the 2-D extrapolation compared to 3-D spillway models.