Development of an Innovative Lattice Boltzmann Hydraulic Model for Shallow Water Flows

Abstract

The development of an innovative Lattice Boltzmann hydraulic model for shallow water flows is presented. The model (CaLB) uses a multi relaxation time (MRT) approach and a cascaded collision operator based on central moments, different from the standard linear collision operator generally used. CaLB is considered for different purposes: reproducing the dynamics of multilayer shallow water flows and modeling large-scale urban floods. Although a variety of models allowing numerical investigation of single and multi-layer shallow water flows, based on continuum and particle approaches, have been widely discussed, there are still some computational aspects that need further investigation. The use a multilayer model (CaLB-N) allows obtaining a description of the vertical variation of hydrodynamic quantities of largescale geophysical flows and deepening the computational aspects of the density layered shallow water flows. The simulation of flood events in urban areas risk is also investigated, introducing a new porosity approach, aimed at developing technical solutions for the assessment and mitigation of flood risk. The model is validated through comparisons with experimental and numerical results from test cases available in literature, yielding very promising results.