[01] Ashraf Balabel, Mechanical Engineering Dept., Taif University, Taif, Hawiyya, Kingdom of Saudi Arabia.

The present paper introduces numerical simulations for one of the most challenging problems of two-phase flows; namely, the unsteady movements of dam break flow considering the turbulence effects. A novel numerical method is developed and validated for solving such complicated problem by solving the Reynolds-Averaged Navier Stokes equations over a regular and structured two-dimensional computational grid using the control volume approach. The standard k- turbulence model is applied for predicting the turbulence characteristics of the dam break flow. The transient evolution of the dam free surface is predicted by the level set method. The effects of the geometrical parameters of the initial dam shape and the density ration of the two phases on the dam front movement and dam topological changes are investigated. The obtained results showed a faster movement of the dam front in the downstream direction by increasing the dam height and the density ratio. Moreover, the topological changes of the dam free surface in later evolutions are also predicted.

Dam Break Problem, Level Set Method, Numerical Simulation, Turbulence Modeling, Two-Phase Flow

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