Author(s): Alessia Ferrari; Renato Vacondio; Paolo Mignosa

Linked Author(s): Renato Vacondio

Keywords: Urban inundations; Flood modelling; Porous shallow water equations; Subgrid model

Abstract: With the aim of modelling urban floods at a large-scale, this work presents a numerical model solving the twodimensional Shallow Water Equations with porosity. The finite volume scheme, which adopts an HLLC Riemann solver, preserves the C-property also along wet and dry fronts. The model is parallelized on Graphic Processing Units (GPUs) in order to reduce the computational burden and it discretizes the computational domain with a Block Uniform Quadtree grid that allows adopting variable resolutions while preserving the GPU efficiency. The model has been applied to simulate the propagation of a severe flood wave on a river in Northern Italy potentially affecting a highly urbanized area of about 400 km2. The results are similar to that provided by a high-resolution model with resolved buildings, but with a reduction of the runtimes of about 60%.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p0947-cd

Year: 2023