(215h) CFD Modeling of Particle Segregation in Gas-Solid Systems

This work highlights ongoing efforts to develop and improve the modeling of particle segregation and mixing in industrial-scale fluidized systems. This is of interest in systems containing particles of different densities or in systems with high levels of particle fines. In both cases, a reasonable prediction of mixing and segregation effects may be necessary for obtaining a suitable CFD model of the fluidized system. Physically, the segregation and mixing of particles in a system is determined by the interplay between differences in drag, gravitational, and buoyancy forces which drive particle segregation and particle collisions and contacting which will restrict it. In CFD approaches that are suitable for industrial-scale modeling, such as Multiphase Particle-in-Cell (MP-PIC), the drag, gravity, and buoyancy forces are readily calculated. The particle collisions and contacting phenomena, however, are not so easily included and CFD modeling of particle segregation and mixing phenomena has historically been difficult as a result. In this work, a new model has been developed for improving the modeling of particle segregation and mixing in simulations with the MP-PIC approach. The development of this model will be presented along with validation against experimental segregation data for gas-solid fluidization.