The aim of this paper is to investigate the capability of the 2D and 3D numerical models to simulate sudden dam break flows in the presence of an obstacle. The 2D-FV model is proposed based on Finite Volume method (FVM) to solve shallow water equations. The commercially available CFD software package Flow-3D solved Navier-Stock equations along the volume of fluid (VOF) method to track the location of the free surface at the air water interface. | BÀI BÁO KHOA H C 2D AND 3D NUMERICAL EVALUATION OF DAM-BREAK WAVE ON AN OBSTACLE Le Thi Thu Hien1; Do Xuan Khanh1 Abstract: The aim of this paper is to investigate the capability of the 2D and 3D numerical models to simulate sudden dam break flows in the presence of an obstacle. The 2D-FV model is proposed based on Finite Volume method (FVM) to solve shallow water equations. The commerciallyavailable CFD software package Flow-3D solved Navier-Stock equations along the volume of fluid (VOF) method to track the location of the free surface at the air water interface. Very good agreement of several hydraulic characteristics such as water level profile, flooding map, velocity map and force versus time history due to dam-collapse wave exerted on the obstruction produced by both presented models can be observed. Keywords: 2D-FV, Flow-3D, dam break wave, obstacle. 1. INTRODUCTION * Dam failures have been responsible for devastating consequences such as loss of life or destruction of property because of extreme flooding in the downstream valley. The assessment of the capability of structures to withstand flood actions is useful in emergency planning. Numerical models are useful in investigating and predicting possible flooding scenarios, which can then be used to formulate suitable flood hazard mitigation measures. Some models solved the shallow water equations (Aureli et al., 2015; Sandra Soares Frarao et al., 2008), whereas some models use 3D turbulence model (Kang et al., 2012). Much attention was paid to the hydrodynamic parameters of dam-break flows, such as velocity, discharge and free surface profile in the channel. However, the hydrodynamic forces acting on the structures which is one of the most important factor to evaluate the effect of dambreak flow to downstream structure is still ignorable. This is not because it is not important, but it is because the dam-break flow is very fast, dangerous and very difficult to measure the force accurately. Therefore, .
