Special Session 63: 

Well-Balanced Positivity Preserving Central-Upwind Scheme with a Novel Wet/Dry Reconstruction on Triangular Grids for the Saint-Venant System

Xin Liu
Southern University of Science and Technology
Peoples Rep of China
Co-Author(s):    Jason Albright, Yekaterina Epshteyn, Alexander Kurganov
Abstract:
In this paper, we construct an improved well-balanced positivity preserving central- upwind scheme for the two-dimensional Saint-Venant system of shallow water equations. As in [Bryson et al., M2AN Math. Model. Numer. Anal., 45 (2011), 423{446], our scheme is based on a continuous piecewise linear discretization of the bottom topography over an unstructured triangular grid. The main new technique is a special reconstruction of the water surface in partially flooded cells. This reconstruction is an extension of the one-dimensional wet/dry reconstruction from [Bollermann et al., J. Sci. Comput., 56 (2013), 267{290]. The positivity of the computed water depth is enforced using the ``draining time-step tech- nique introduced in [Bollermann et al., Commun. Comput. Phys., 10 (2011), 371{404]. The performance of the proposed central-upwind scheme is tested on a number of numerical experiments.