A Multi-Phase ISPH Model for Simulation of Dam Break Waves on Movable Bed

Rasoul Memarzadeh, Gholamabbas Barani, Mahnaz Ghaeini-Hessaroeyeh

Tuesday 30 june 2015

17:45 - 17:48h at Mississippi (level 1)

Themes: (T) Sediment management and morphodynamics, (ST) Sediment transport mechanisms and modelling, Poster pitches

Parallel session: Poster pitches: 7A. Sediment - Erosion

Failure of dams or flood control structures cause flood waves which can erode and transport large amounts of sediments. In this phenomenon, flood flows, sediment transport and bed changes occur simultaneously. The violent free surface associated with the interface _ow and mixing process makes the modeling of such highly erosive and transient _ow even more complicated. For the numerical modeling of dam break waves on the movable bed, a multi-phase model is required. In the conventional multi-phase models, the governing equations of fluid and sediment phase are expressed in the Eulerian form and the common mesh based Eulerian methods such finite volume method are used for solving these equations. In this paper, an advanced application of the Incompressible Smoothed Particle Hydrodynamics (ISPH) method, which simulates the dam break waves on movable bed as a free surface multi-phase flows, is illustrated. SPH is a Lagrangian and mesh free particle based method which is successfully used for numerical modeling of the free surface flows such as dam break waves. Nevertheless, the SPH applications to model the dam break have been limited to the simulation of the fixed bed dam break. In this study, a novel multi-phase model based on the ISPH method has been developed for 2DV numerical modeling of dam break waves on movable bed. Moreover, in the present model, instead of using the separate equations for each phase, system is considered as multi-density and multi-viscosity, and a single set of equations are solved for the whole _ow _eld. Validations of the model are performed by modeling the dam break on the movable bed. Comparison between the computational results and experimental data proves the ability of the multi-phase ISPH model to accurately simulate the dam break waves over movable bed.