Numerical simulation study on mixing characteristics of binary Geldart-D particles in a pressurized fluidized bed

Abstract

Understanding the mixing behaviors of different particles is significant for improving the mass and heat transfer performance of a pressurized fluidized bed. A numerical simulation study on the mixing behavior of binary Geldart-D particles in a pressurized bubbling fluidized bed is performed based on the CFD-DEM method. The mixing characteristics and bubble behavior of binary Geldart-D particles with different physical properties under elevated pressure are investigated in the current study. Increasing the fluidization gas velocity u g and operating pressure P could promote the mixing of the particles. Raising the operating pressure P would cause a smaller bubble size and large bubble quantity at the same fluidization number u g /u mg . Higher operating pressure P and fluidization number u g /u mg could create a stable and uniform distribution of jetsam in the fluidized bed. • Mixing behaviors in the pressurized fluidized bed are investigated by CFD-DEM. • Minimum fluidization velocity decrease as the increase of operating pressure. • Bubble size decreases as raising operating pressure of fluidized bed. • High operating pressure and gas velocity promote the mixing rate of particles.