Hydraulic simulation is becoming a very widely used tool to provide information about the duration, the extension and the magnitude of a flooding episode. In the last decade, the advances in the numerical schemes, connected to the evolution experimented in the power of computers have allowed to aim for maximum accuracy in the results instead of working with simplified models. In particular, two main implementations have been extensively developed in the recent years: 1D-2D coupled numerical models and fully 2D models under GPU technologies. These strategies allow to simulate a wide range of applications over large domains and time scale problems, computing them at an affordable cost. Both 2D model and 1D-2D coupled model are implemented using a finite volume framework using a conservative upwind cell-centered formulation based on Roe's Riemann solver across the edges. In particular, the 1D-2D model is constructed with a novel technique that computes the average values and solves the Riemann Problem at the coupled edges while the 2D model uses the same numerical method performing the computation by means of the last GPU technology. The topography is represented by means of triangular unstructured meshes for the 2D model and with cross sections for the 1D domain inside the coupled model. Both models were previously validated with experimental measurements, analytical solutions in academic and realistic configurations. A real river configuration with different scenarios and field data is presented. Not only the error made with respect the measurements is analyzed, but also the CPU time is evaluated in order to decide whether or not to use the 1D-2D coupled or the GPU model.
Morales-Hernández, Mario; Lacasta, Asier; Murillo, Javier; Brufau, Pilar; and García-Navarro, Pilar, "A Comparative Study Of Accuracy And Performance Between A Fully 2D GPU Based And A 1D-2D Coupled Numerical Model In A Real River" (2014). CUNY Academic Works.