Two-Dimensional Finite Volume Model for Dam Break Modeling on Unstructured Triangular Grids

A numerical model based upon a second-order upwind finite volume method on unstructured triangular grids is developed for solving shallow water equations. As assumption of very small depth in downstream of the dam can change nature of the dam break problem which leads to incorrect results, the HLL approximate Riemann solver is used for the computation of inviscid flux functions, which makes it possible to handle discontinuous solutions and has “vacuum preserving property”. By using of a specific technique, artificial spreading of dry-wet front has been removed. A multidimensional slope-limiting technique is applied to achieve second-order spatial accuracy and to prevent spurious oscillations. To alleviate the problems associated with numerical instabilities due to small water depths near a wet/dry boundary, the friction source terms are treated in a fully implicit way. A third-order total variation diminishing Runge– Kutta method is used for the time integration of semi-discrete equations. The developed numerical model has been applied to several test cases as well as to real flows. Numerical tests proved the robustness and accuracy of the model. The code has been practiced for simulation of dam break analysis of Torogh, Kardeh and Barzou in Iran

Two-Dimensional Finite Volume Model for Dam Break Modeling on Unstructured Triangular Grids Keywords:

finite volume , SWE , HLL , dam break , dry bed , high resolution , EAP