Numerical Study of the Fluidization of the Binary Types of Particles Using SOM-KTGF-MT

The second-order moment of kinetic theory of granular flow (SOM-KTGF) has been verified in predicting the particle-laden flow in the median concentration, by the four-way coupled second-order method (FW-SOM) established via coupling the gas phase second-order turbulence model [1]. The anisotropic SOM-KTGF remedied the shortage of the classic isotropic KTGF in predicting the “dilute” phase of particles in the fluidized risers. These particles of the dilute phase in the fluidized bed were suspended in the reactor and less affected by the other particles surrounded. As a result, these particles showed the behaviour of the high inertia and high anisotropic fluctuation. In the previous study, the FW-SOM and SOM-KTGF demonstrated the superior to the classic KTGF in the numerical study of the fluidization.

A novel model of the SOM-KTGF for multi-type particles (SOM-KTGF-MT) was proposed in this study to investigate the fluidization of the particle mixture with binary types. The particles in the mixture differ in all types of the physical properties such as the density, size, and restitution coefficient et al. In the model, SOM-KTGF-MT, the conservations equations of the volume fraction, velocity and the velocity fluctuation of particles were solved for each type of particles. In this study, SOM-KTGF-MT was applied to simulate the flow behaviour of gas-solid flow with different size and density of particles in the fluidized bed. The anisotropic fluctuation of the binary types of particles and effects of the particle-particle interaction were investigated in terms of the particle distribution and turbulent characteristics.

[1] D. Sun. Four-way coupled second-order method of two-fluid model for gas-particle flow and the numerical simulation in horizontal channels. Powder Technology 390 (2021) 354–368