Well-Balanced Inundation Modeling for Shallow-Water Flows with Discontinuous Galerkin Schemes

Abstract

Modeling coastal inundation for tsunami and storm surge hazard mitigation is an important application of geoscientific numerical modeling. While the complex topography demands for robust and locally accurate schemes, computational parallel efficiency and discrete conservation properties of the scheme are required. In order to meet these requirements, Runge-Kutta discontinuous Galerkin numerical methods are attractive. However, maintaining conservation and well-balancedness of these schemes with wetting/drying boundary conditions poses a challenge. We address this issue by a local nondestructive modification of the flux computation at boundary cells, which maintains accuracy, conservation and well-balancedness. The development can be viewed as a specialized flux limiter, which proves its usefulness with three different test cases for inundation simulation.