MULTI-SCALE SIMULATION OF REACTIVE FLOW THROUGH A FIXED BED OF CATALYST PARTICLES

We investigate the reactive flow through a fixed bed of catalyst particles. Our simulation method belongs to the class of multi-scale approaches and combines nano scale DFT (Density Functional Theory) computations, mean-field kinetics at the micro scale and fully-resolved hydrodynamic simulations at the millimetric scale. At this stage, the simulations at the chemical (nano and micro) scales provide the rate constants needed by the hydrodynamic model in a one-way coupling. In this paper, we focus on the fully-resolved millimetric scale simulation model based on a Distributed Lagrange Multiplier/Fictitious Domain (DLM/FD) method combined with a Finite Volume/Staggered Grid scheme and a high order reconstruction at the fluid/solid interface. In particular, we present various DLM/FD algorithms that supply a divergence free velocity field, a property crucial for the accurate discretization of the additional diffusion convection equations modeling the chemical reactions. Our method is implemented in our fully MPI platform PeliGRIFF (www.peligriff.corn) dedicated to the multi-scale simulation of flows with particles/bubbles/drops. We illustrate the assets of our simulation method on the reactive flow through a pack of 3D cylinders and discuss the forthcoming developments required to extend our approach to a two-way coupling in which the reaction rates are affected by the flow dynamics.