سال انتشار: ۱۳۹۰

محل انتشار: اولین کنفرانس بین المللی و سومین کنفرانس ملی سد و نیروگاههای برق آبی

تعداد صفحات: ۹

نویسنده(ها):

OMID SEYEDASHRAF – MSc Student of Hydraulic Engineering
ALI AKBAR AKHTARI – Assistant Professor
HEJAR JEBELI AQDAM – M.Sc. Student of Hydraulic Structures

چکیده:

When a dam is breached, calamitous flash flooding occurs as the impounded water flees through the opening into the downstream river, which is followed by massive liveand property lost. However, taking into account the large scale of the phenomenon, a numerical scheme remains the preferred method for the provisional studies. FiniteVolume Method (FVM), Finite Difference Method (FDM) and Finite Element Method (FEM) are the three main numerical methods used in simulating hydraulic incidents.The use of non-linear Shallow Water Equations (SWEs) has become standard for dambreakflow modeling and has been proved both useful and convenient, albeit the existence of significant ambiguities due to the simplifying assumptions andapproximations used in the SWEs. In the present study attempts were made to numerically investigate the fluid flow characteristics of dam-break phenomenonthrough different governing equations and numerical methods. The resolution of 2D SWE and 3D Navier-Stokes (NS) equations in the dam-break simulation, is put side byside the experimental data, validated and compared the accuracy of both models. TheCFD analysis is executed by means of the commercial software package Fluent. The volume of fluid (VOF) model is employed to depict the air-water interaction at the freesurface. It has been concluded that, both 2D SWE and 3D NS models are capable of capturing the dam-break shocks reasonably accurate, yet, considering the CPU timeand overall evaluations, the 2D model with the SWE as the governing equations, ispreferable to the 3D NS model in numerical simulations of the dam-break phenomena.