Numerical Modeling of Flow and Aeration System of the AZAD Dam’s Spillway Using ANSYS FLUENT Model

Cavitation is one of the most important problems that may occur due to high flow velocity in dam spillways. In order to predict of dam spillway structure during operation, Azad dam spillway hydraulic model has been modeled in Tehran Water Research Institute.

In this study, using computational fluid dynamics in the form of a finite volume method used in ANSYS FLUENT software, flow modeling in these channels, and a fluid volume model (VOF) in a three-dimensional state, including two-phase flow of water and air, used for Considering current turbulence, k-ε model has been used. In order to confirm the results of the model, a comparison was made with the results of a hydraulic model implemented without the aero-damping system of Azad spillway.

Then, in order to confirm the location and number of aeration systems, two scenarios (two and three aeration systems) including step ramp (RAMP) on the floor and the wall of the duct with a suitable slope and the installation of the aeration slot in the wall have been used, which sends air near the floor And the walls will be.

Then, by checking flow parameters such as speed, pressure and cavitation index, overflow with two aeration systems was confirmed as the best option.