Meso-Scale Modeling: The EMMS Model for Gas-Solid Systems

This chapter introduces the EMMS model for gas-solid two-phase flow and the motive for this series of work. The EMMS model focuses on the mesoscale phenomenon of particle clustering, correlating it to the micro-scale of single particles and the macro-scale of the vessel operating conditions, material properties, and boundary conditions by analyzing the compromise between dominant mechanisms to define the meso-scale stability condition. The EMMS model can be solved for the eight parameters that describe the meso-scale structure and capture the so-called choking and drag-reduction phenomena in gas-solid fluidization systems, and further enables the intrinsic regime, operation diagram and overall fluid dynamics of systems to be determined. This chapter provides a solid basis to integrate the EMMS model with computational fluid dynamics (CFD) simulations and develop the EMMS paradigm.