Numerical simulation on distribution characteristics of flexible filamentous particles in a fluidized bed dryer

Distribution characteristics of flexible filamentous particles are investigated in a fluidized bed dryer. The gas–solid two-phase flow in the riser was simulated by Euler–Lagrange method to capture fluidization behavior. Namely, the air flow was defined as continuous phase and the individual flexible filamentous particle was simulated with the chain model. Then the dynamic characteristics of particle distribution in the riser were investigated numerically and experimentally, and the influences of fluidization parameters on particle distribution characteristics were discussed in detail. The research results show that the distribution of flexible filamentous particles in the riser is not uniform, and the formation and development of local regions with higher particle concentration or particle clusters could be found. Furthermore, the gas flow rate and the material flow rate have profound influence on the fluidization behavior and the distribution characteristics of particles. The simulation results are consistent with the experimental findings. Therefore, the simulation model is valid to predict the dynamic behavior of flexible filamentous particles.