Author(s): Max Bitsch; Jesper Grooss; Allan Engsig-Karup
Linked Author(s): Max Bitsch
Keywords: Shallow Water Equations Subgrid method Unstructured Meshes
Abstract: We present a new simulation method for solving the shallow water equations on unstructured meshes, designed for complex terrain with both wet and dry areas. This method connects high-resolution bathymetry data with a coarse free-surface elevation, resulting in increased volume and friction accuracy and leading to improved flood predictions. Velocities are calculated on the coarse mesh, which, in combination with the unstructured mesh, allow for adaptive grid refinements, overcoming limitations in conventional simulators that utilize fixed uniform meshes. The enhanced flood predictions are demonstrated by comparing floodplain solutions on a uniform mesh and on a refined mesh with increased resolution in critical areas.
Year: 2025