Development of a multilayer cascaded CO based lattice Boltzmann model for shallow water flows

In this work a multi relaxation time (MRT) cascaded (CaLB) Lattice-Boltzmann model (LBM) is developed and used to reproduce the dynamics of a two-layered liquid, made of immiscible shallow-layers of different density. The model solves the shallow water equations using the collision operator based on central moments considering two separate sets of LBM equations (particle distribution function PDF), one for each layer. The coupling terms between the two sets have been defined as external forces and allow the mutual actions between layers. Results obtained from the LBM model presented in this paper are compared with experimental and numerical results from benchmark test cases available in literature. First results are very promising, especially for the density or gravity currents.