A DNS Approach Dedicated to the Analysis of Fluidized Beds

摘要

The numerical modelling of fluidized bed is widely encountered in fundamental research and industrial applications in the field of chemistry, energy or material processes. The problem is complicated by the presence of different length and time scales describing the particles and the reactors. Several modellings exist for simulating particulate flows. In averaged Eulerian models where the size of the particles is small compared to the continuous medium characteristic scale, fluid-particle interactions are taken into account using constitutive laws. In the present study, a numerical model is proposed to describe the fluid-particle interactions at the particle scale, based on fixed Eulerian structured grids, penalty methods and Volume Of Fluid (VOF) techniques. Our interest is to build a general model and approximation methods efficient enough for leading Direct Numerical Simulations of paiticulate flows without any requirements of physical parametrization such as particle-particle interactions. In addition, our motivation is to analyze the results of the numerical experiments in terms of equivalent macroscopic quantities such as velocity fluctuations, granular pressure or solid fraction.